ValorizationofDatePitsasanEffectiveBiosorbentforRemazol ...downloads.hindawi.com/journals/jchem/2020/4173152.pdf · ResearchArticle ValorizationofDatePitsasanEffectiveBiosorbentforRemazol

Research ArticleValorization of Date Pits as an Effective Biosorbent for RemazolBrilliant Blue Adsorption from Aqueous Solution

A Thiam12 K Tanji 1 O Assila 1 M Zouheir 1 Redouane Haounati2 A Arrahli 3

A Abeid4 S Lairini1 R Bouslamti1 F Zerouq1 and A Kherbeche1

1Laboratory of Catalysis Process Materials and Environment School of Technology University Sidi Mohamed Ben AbdellahFes Morocco2Physical Chemistry and Environment Team Faculty of Science Ibn Zohr University Agadir Morocco3Euromed Research Center National Institute of Applied Sciences Euro-Mediterranean University of Fez Fes Morocco4Laboratory Food Microbiology Biotechnology and Environment ISET Rosso Mauritania

Correspondence should be addressed to K Tanji karimtanji1992gmailcom

Received 24 February 2020 Revised 15 July 2020 Accepted 24 August 2020 Published 8 October 2020

Academic Editor Jose Morillo

Copyright copy 2020 A +iam et al +is is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

In this work the adsorption of Remazol Brilliant Blue (RBB) over raw date pits (RDPs) as an inexpensive adsorbent has beenexamined In addition all parameters such as the adsorbent mass solution pH RDP particle size RBB initial concentration andtemperature on the adsorption of RBB influencing the adsorption procedure were studied to provide fundamental information ofthe adsorption equilibrium +e characterization of RDP material is investigated by X-ray diffraction (XRD) scanning electronmicroscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) Based on the calculation the kinetic rate of the ad-sorption was well modeled by pseudo-second-order and Langmuir isotherm Surface functional groups of RDP have substantiallybeen influenced by the adsorption characteristics of RBB +e capacity of the adsorption has achieved 105mgg and a removalefficiency of 904 at 15 gL RDP mass 40mgL initial dye concentration pH 2 temperature of 328K 40 microm particle size andcontact time of 50min +e capacity of the adsorption could reach 198mgg by increasing the ionic strength of RBB solutionDesorption tests showed that RDP adsorbent has the disadvantage of losing efficiency while reusing for many cycles However itstill abundant and inexpensive +erefore RDP can be used as a potential low-cost bioabsorbent for the elimination of RBBfrom wastewater

1 Introduction

Pollution refers to the deterioration of the environment byunnatural materials causing the disappearance of severalspecies of animals plants as well as the appearance of newphenomena which has harmful effects on human healthincluding global warming [1ndash3] +e effects of this pollutionaffect not only the air and the soil but also a large part of thewater Dyes are used in many industrial sectors such astextiles paper leather food and cosmetic industries[4]Moreover these industries consume huge quantities ofwater Once those dyes are released they cause significantdamage to human health such as the mutagenic and car-cinogenic effects [5ndash8] and changes in the aquatic

environment [9] when they are discharged into the envi-ronment without or with insufficient treatment [10ndash12] Toreduce the impact of this pollution several techniques havebeen developed and tested in the treatment of effluentsloaded with dyes namely biological process [13] coagu-lationflocculation [14] photodegradation [15ndash18] ozona-tion [19 20] oxidation [21 22] and membrane separation[23ndash25] +e adsorption technique is considered as one ofthe most effective methods that has been successfullyadopted for removing dyes from wastewater [26ndash31] due toits low cost and availability Allowing easy removal of dyesfrom aqueous solutions over different materials and onactivated carbon in particular [32] has always been thesubject of much work [33 34] Many adsorbents have been

HindawiJournal of ChemistryVolume 2020 Article ID 4173152 14 pageshttpsdoiorg10115520204173152

investigated for the removal of dyes in recent years [35] suchas clay [36 37] layered double hydroxides [38] metal oxides[39] goethite modified natural [40] and sediments [41 42]+e activated carbon has a high cost Hence the need to lookfor cheaper effective and natural available adsorbent istherefore interesting [43] Bioadsorbent materials have beenproposed as alternative adsorbents for dyes EspeciallyRDPs have received considerable attention for its propertiessuch as low cost natural availability and no threat to theenvironment +e fruit of the date palm is composed of afleshy pericarp and seed Pits of date palm (seed) are a wasteproduct of many date fruit-processing plants producingpitted dates date powders date syrup date juice chocolate-coated dates and date confectionery [44] In addition theRDP are very widely distributed and abundant which makethem the promising environmental adsorbents that can beused in industrial processes [3] Javid et al have studied theremoval of bisphenol A and nonylphenol from aqueoussolutions using carbonized date pits modified with ZnOnanoparticles and they found maximum removal efficiencyunder optimal conditions was 95 [45 46] However ad-sorption of RBB onto the RDP was not fully investigated[43]+erefore the objective of this work is to investigate thephysics and chemical properties of RDP bioadsorbent usingmultiple methods such as X-ray diffraction (XRD) scanningelectron microscopy (SEM) and Fourier-transform infraredspectroscopy (FTIR) and then to evaluate the effectiveness ofusing RDP as natural eco-friendly and low-cost bio-adsorbent for the removal of RBB in aqueous mediaMoreover various parameters influencing the adsorptionprocedure of RBB adsorption on the RDP bioadsorbentsuch as the adsorbent mass solution pH RDP particle sizeand RBB initial concentration were studied On the otherhand the ionic strength effect using BaCl2 on the adsorptionequilibrium is important to highlight as well

2 Materials and Methods

21 Preparation of RDP Moroccan dates were shelled andthe pits were collected and sorted in order to remove theimpurities and then dried at a temperature of 110degC in theoven for 24 hours +en the bioadsorbent was ground in agrinder and sieved in order to obtain particles of the samesize with a diameter of 40 63 125 and 200 microm RDPcontains an approximate percentage of hemicellulose lignincellulose and carbohydrates [3]

22 Adsorbate +e dye considered in this study is RemazolBrilliant Blue (RBB) analytical grade purchased for Sigma-Aldrich it has the chemical formula C22H16N2Na2O11S3and its maximum absorption band is located at the wave-length of 590 nm +e main problems associated with RBBdye in textile wastewaters are resistant to biodegradationhighly visible due to its bright color even in very lowconcentration of dye (lt1mgL) in the effluent and verytoxic difficult to remove by traditional methods

23 Adsorption Study In this study a stock solution wasprepared from the RBB dye +e adsorption study was

carried out by using 1 g of RDPmixed with a solution of RBBat room temperature under continuous stirring in a batchsystem In order to investigate the kinetic adsorption severalsamples were collected each 5min to measure its concen-tration using UV-visible spectrophotometer (VR-2000) at awavelength of 590 nm Nevertheless before the measure thesuspension was centrifuged to separate the natural adsorbentfrom the RBB liquid During the adsorption experimentHCl (05M) and NaOH (05M) from Sigma-Aldrich wereused to adjust the pH solution

+e RBB removal was calculated using following formula[43 47]

removal() C0 minus Ct( 1113857

C0times 100 (1)

where C0 and Ct are the concentration of RBB at t 0 and attne0 respectively

+e adsorption capacity of RDP for RBB removal wasobtained by applying the following equation [48]

qe C0 minus Ce( 1113857

mtimes V (2)

where qe (mgg) is the adsorption capacity at equilibrium C0(mgL) is the initial concentration of RBB Ce (mgL) is theequilibrium concentration of RBB V (L) is the RBB solutionvolume and m (g) is the RDP mass

24 Characterization Techniques +e X-ray diffraction (XprimePERT PRO) equipped with a detector operating at 40 kV and30mA with Cu Kα radiation (λ1540598 A) infraredspectroscopy (VERTEX 70) and scanning electron mi-croscopy (QUANTA 200) were used to identify the com-position and the morphology of adsorbents materials toexplore the chemical composition of RDP

3 Results and Discussion

31 RDP Characterization

311 X-Ray Diffraction (XRD) +e X-ray pattern of RDPdata is given in Figure 1 It can be observed that dif-fractogram of bioadsorbent RDP does not exhibit a hori-zontal basic line and displayed the presence of littlediffraction peaks +e broad diffraction peak located be-tween 20deg and 25deg could be ascribed to carbon speciesaccording to the native cellulose (C6H12O6) and to xylanedehydrate (C10H12O9middot2H2O) [49]On the contrary the otherfew small diffraction peaks may be attributed to the presenceof a small amount of crystalline matter +erefore this resultindicated that the major part of the matter is amorphous

312 Scanning Electron Microscopy (SEM) SEM analysis ismade on RDP before adsorption (Figures 2(a) and 2(b))+ematerial has a smooth porous surface indicating a goodpossibility of trapping RBB adsorption on the adsorbentsurface On the contrary after the RBB is adsorbed into RDPbiomaterials the SEM observation shows the surface of RDPcharged with RBB displaying a rough and corroded surface

2 Journal of Chemistry

due to the coverage of the pores by the RBB dye moleculesadsorbed in Figures 2(c) and 2(d) +is result indicated thatthe raw date pits (RDPs) could be an efficient bioadsorbentto remove hazardous dyes in the wastewater

313 Fourier-Transform Infrared Spectroscopy +e RDPinfrared spectrum studied in this work (Figure 3) allows usto observe a characteristic broad band around 3400 cmminus1

corresponding to the O-H stretching vibrations +e

1000 cmminus1 band confirms the existence of an alcohol and2800 cmminus1 corresponds to the valence vibrations of C-Hhybridized sp3 that can be attributed to the presence ofnative cellulose (C6H12O6) and xylane dehydrate(C10H12O9middot2H2O) which was already confirmed by XRDanalysis In addition the band located at 400 cmminus1 corre-sponds to the deformation vibrations of δC-H and the bandat 1600 cmminus1 according to the deformation vibrations of δO-H+e analysis of this graph shows that our RDP biomaterialis an organic compound essentially containing the carbon

10 15 20 25 30 35 40 45

Inte

nsity

(au

)

2 thetadeg

Carbon

Figure 1 XRD pattern of RDP

(a) (b)

(c) (d)

Figure 2 Scanning electron microscopy (SEM) images of RDP (a b) before adsorption (c d) after adsorption

Journal of Chemistry 3

atom hydrogen and oxygen [50ndash52] After adsorption ofRBB (Figure 3) the functional groups present on the surfacesof RDP show band shifting for possible involvement ofhydroxyl groups around the broad peak at 3400 cmminus1 +ebroad peak shifted to 3411 cmminus1 +e initial peak at2922 cmminus1 was shifted to 2928 cmminus1 and showed an alkanegroup was bonded to C-H stretch +e strong band at1622 cmminus1 was shifted and corresponding to the aminegroup with N-H bond +erefore the diminished peaksshowed that all the functional groups are completely in-volved in the adsorption process of RBB over RDP [53ndash55]

32 Effect of Different Parameters on the Adsorption Efficiency

321 Initial Solution pH Effect +e pH definitely affects theadsorption of the dye In order to determine the adsorptionbehavior of the RBB dye under different pH values (from 23to 903) a series of adsorption experiments were carried outusing 40mgL of RBB 1 gL RDP particle size of 63 microm atroom temperature and stirring at 250 rpm Figure 4 showsthat there is a variation in the RBB removal as a function ofpH Accordingly when the pH raises from 2 to 9 the ad-sorption removal decreases from 865 to 648+is is due tothe neutralization of the negative charge on the surface of theadsorbents by the charged dye molecule [56] An increaseddiffusion process facilitates the fixation of the dye on theactive sites of the adsorbents [57] Figure 5 shows that thepHpzc of raw RDP is 601 [58]

322 Effect of RDP Mass +is study makes it possible toevaluate the influence of the adsorbent mass in order todetermine the optimal mass which coincides with a betterdispersion of the adsorbent particles (RDPs) Figure 6(a)below represents the variation in the adsorption capacity as afunction of time and of the adsorbent mass which varies

from 05 to 3 g using 40mgL of RBB particle size of 63 micrompH 4 at room temperature and stirring at 250 rpmFigure 6(b) shows an increase in the removal with the in-crease in RDP mass from 63 to 821 when the mass ofadsorbent raises from 05 to 3 g Conversely there is a de-crease in the adsorption capacity from 1042 to 58mgg +eincrease or the decrease in the first 30min was fast and thenfollowed by the flat curve proving the saturation of theadsorbent +e crossing point of the removal and the ad-sorption capacity correspond to the optimal mass of 15 g(Figure 6(b)) +ese results can be explained by an increasein the active sites when the masses are large Consequentlythe probability of contact between the RBBmolecule and thesite of the adsorbent support also increases [59]

323 Effect of Initial RBB Concentration +is study makesit possible to reach the maximum values of adsorptioncapacity of RBB which represents the saturation of all the

4000 3500 3000 2500 2000 1500 1000 500

1422

56

2856

31

2922

45

Tran

smitt

ance

()

Wavenumber (cmndash1)

After adsorption Before adsorption

34113416

225

6

1041

21

Figure 3 Infrared spectrum of RDP before and after RBBadsorption

2 3 4 5 6 7 8 9 100

20

40

60

80

100

Rem

oval

()

pH

Figure 4 pH solution effect on the RBB adsorption

0 2 4 6 8 10 12 14

0

2

4

6

8

pHi

pHf

Figure 5 pHpzc of raw date pit


active sites available on the surface of the adsorbent +eeffect of the initial RBB concentration was studied at dif-ferent initial RBB concentrations varying between 10 and60mgL using 1 gL RDP particle size of 63 microm and solutionpH 4 at room temperature and stirring at 250 rpmAccording to Figure 7(a) there is a fairly rapid increase inthe adsorption capacity in the area of high concentrations+e increase or the decrease in the first 30min was fast andthen followed by the flat curve proving the saturation of theadsorbent +is absorption capacity continues to decreasewith the decrease in the RBB initial concentration [60 61] Insummary the adsorption capacity of RBB on the adsorbentincreases from 669 to 1056mgg when the initial con-centration of RBB increases from 10mgL to 60mgL +eseresults could be explained by the existence of strong in-teractions between the RDP surface and the RBB +e sat-uration appears when the active sites are totally occupied onthe adsorbent surface [62] Plotting the adsorption capacityand the removal as a function of the equilibrium concen-trations shows an intersection point of two curves whichcorresponds to the optimal concentration which is 40mgLas shown in Figure 7(b)

324 Effect of the Particle Size In order to study the effect ofRDP particles sizes a series of experiments were performedwith different particles sizes from 40 to 200 microm using 40mgL of RBB 1 gL RDP pH 4 at room temperature andstirring at 250 rpm Figure 8 illustrates that decreasingparticles size enhanced the adsorption capacity the 40 micromparticle size has the highest RBB removal (95) Othersmesh presented lower removal between 72 and 856Although the 200 microm size showed a slow adsorption about4964 at 60min this evolution could be explained by the

link between the effective surface area of RDP particles andthe adsorption efficiency in which the small particles have alarge surface area exposed to adsorption and hence highadsorption [63]

325 Effect of Temperature +e adsorption removal of RBBon the RDP adsorbent increases from 8221 to 94 when thetemperature rises from 298K to 328K using 40mgL of RBB1 gL RDP particle size of 63 microm pH 4 and stirring at250 rpm (Figure 9) +is small increase in adsorption re-moval indicates that the adsorption process is endothermic[64] the system at low temperatures requires a high energyto reach equilibrium although this system at high temper-atures requires less energy to reach equilibrium+e effect oftemperature on the removal is in agreement with the resultsfound by the use of a biomaterial based on RDP [60] +eslight increase in the removal as a function of temperaturecan be explained as follows (i) the increase in the active siteson the RDP surface (ii) the increasing temperature increasesthe mobility of RBB inducing a swelling effect in the internalstructure of RDP which facilitated the penetration of RBBfurther [56]

326 Adsorption of RBB over RDP under OptimumConditions +e adsorption of the RBB dye solution wastested by applying the optimal conditions which are RDPmass 15 gL RBB concentration 40mgL particle size of40 microm temperature 328K and the pH 2 Figure 10 illustratesthe evolution of the adsorption capacity of RBB dye usingraw RDP +e adsorption removal achieved very important100 during 50 minutes with 1154mgg as adsorptioncapacity

0 10 20 30 40 50 600

20

40

60

80

100

120

q max

(mg

g)

Time (min)

1015mgg

2 gL25 gL3 gL

05 gL1 gL15 gL (a)

05 10 15 20 25 30

50

55

60

65

70

75

80

85

Removal ()Adsorption capacity (mgg)

Mass (gL)

Rem

oval

() 8255

60

70

80

90

100

qe (m

gg)

1015mgg

(b)

Figure 6 RDP mass effect on the RBB adsorption (a) and the optimal RDP mass during the adsorption phenomenon (b)


33 Isotherms Adsorption For the study of adsorptionisotherms the Langmuir and Freundlich models were ex-amined and applied to describe the adsorption process ofour experimental results (Figure 11(a)) +e Langmuirisotherm is one of the models which describes a monolayeradsorption It assumes a homogeneous adsorption surfacewith binding sites having equal energies +e linear form ofthe Langmuir isotherm can be expressed as follows [65]

1qe

1

qmax+

1KL times qmax( 1113857

times1

Ce

(3)

where KL (Lmg) is the Langmuir constant Qmax (mgg)represents the maximum adsorption capacity under ex-perimental conditions and Qmax and KL are determinedfrom the plot of Ceqe as a function of Ce

From the correlation factor values shown in Table 1 weconclude that the adsorption of RBB by the RDP is wellrepresented by the Langmuir model with a maximum ad-sorption capacity of 10752mgg that is to say the mech-anism applied corresponds to a monolayer adsorption which

0 10 20 30 40 50 600

20

40

60

80

100

Rem

oval

()

Time (min)

40microm63microm

125microm 200microm

95

Figure 8 RBB removal at different particle sizes of RDP

1015mgg

0 10 20 30 40 50 60Time (min)

0

20

40

60

80

100

120

q max

(mg

g)

60mgL

50mgL

40mgL

30mgL

20mgL

10mgL(a)

10 20 30 40 50 6078

80

82

84

86

88

90

92

94

RemovalAdsorption capacity

Concentration (mgL)

Rem

oval

()

70

75

80

85

90

95

100

105

110

qe (m

gg)

(b)

Figure 7 Initial RBB concentration effect on the adsorption process (a) and the optimal RBB concentration during the adsorptionphenomenon (b)

295 300 305 310 315 320 325 3300

20

40

60

80

100

Rem

oval

()

Temperature (K)

Figure 9 Effect of temperature on the RBB adsorption


involves identical independent and limited adsorption sites[66]

During the study of the Freundlich isotherm(Figure 11(b)) the logarithmic equation used is as follows[65]

Logqe LogKF +1nLogCe (4)

By carrying Log (qe) as a function of Ce we obtain a lineof slope 1n and of ordinate at the origin Log (KF) whichmakes it possible to determine the constant KF and theheterogeneity factor (n)

+e DubininndashRadushkevich model (Figure 12) does notassume a homogeneous surface or constant adsorptionpotential like the Langmuir model His theory of filling thevolume of micropores is based on the fact that the ad-sorption potential is variable and that the free enthalpy ofadsorption is related to the degree of filling of the pores[67 68] +e DubininndashRadushkevich isotherm is given bythe following equation [65]

ln qe ln qmDR minus KDRε2 (5)

0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)

Figure 10 Variation in adsorption capacity of RBB at optimum conditions

0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)

Figure 11 Langmuir isotherm plot (a) Freundlich isotherm plot (b)

Table 1 Adsorption isotherm constants of RBB adsorption ontothe RDP

Freundlich isotherm Langmuir isotherm1n KF R2 Qmax KL R2

058 2392 0890 10752 109 0991


where qmDR is the RDP adsorption capacity at equilibrium(mgg) KDR is the DubininndashRadushkevich constant (mol2kJ2) and ε is the Polanyi potential (Jmol)

According to the values of R2 (Table 2) the RDP is wellrepresented by this model so it can be said that the ad-sorbent support has an average energy of adsorption lessthan 8 kJmol which indicates that physisorption is themajority

34 Kinetic Models +e kinetics of the pseudo-first-ordermodel and the pseudo-second-order defined respectivelyby the following equations

Log qe minus qt( 1113857 Logqe minusk1

2303t (6)

t

q

1k2 q

2e

+t

q (7)

If the Lagergren relation is verified by carrying Ln(qe minus qt) as a function of time (Figure 13(a)) we must obtaina line of slope k1 In addition plotting tqt as a function oftime (Figure 13(b)) we must obtain a line with slope 1qeand ordinate at the origin equal to 1k2 qe2

It is clearly observed that the equation of the pseudo-first-order model is not linear with a correlation coefficientR2 very lower (Table 3) so that the experimental absorptioncapacity is very far to that calculated by this model So wecan deduce that the kinetic of adsorption does not follow thepseudo-first-order model [69] (Figure 13(a)) However itcan be seen from the results obtained (Figure 13(b) andTable 4) and we note that the variation in tqt as a function oftime is very linear and the regression coefficient R2 issatisfactory +erefore we can conclude that the kineticsadsorption of RBB using RDP obeyed the pseudo-second-order model [70]

35 Adsorption ermodynamic Studies +e informationabout the adsorption thermodynamics is very crucial toprovide a better understanding of the adsorption process(Figure 14)+erefore the Vanrsquot Hoff equations were used todetermine the thermodynamic parameters mainly Gibbs-free energy change (ΔGdeg) enthalpy change (ΔHdeg) and en-tropy change (ΔSdeg) of the adsorption process from the ex-perimental data and following equations

ΔGdeg minusRTLnKLdeg

LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889

ΔGdeg ΔHdeg minus TΔSdeg

(8)

where ΔGdeg is the standard free energy kJmol T is theabsolute solution temperature K ΔHdeg is the standard en-thalpy kJmol R is the universal gas constant 8314 JmolKand ΔSdeg is the standard entropy JK

As shown in Table 5 the negative values of ΔGdeg at 298308 318 and 328 indicate that adsorption spontaneity isfavored at these temperatures A similar trend has beenobserved at 308 318 and 328K for the adsorption of RBBonto RDP+e positiveΔH value 4762 kJmol confirmed theendothermic nature of RBB adsorption while the slightly ΔSvalue 0048 kJmolmiddotK reveals an increase in the randomnessat the RBB-RDP-solution interface during the adsorptionprocess [71]

4 Proposed Mechanisms of RBB Adsorption

It was shown that RBB was adequately adsorbed for pHbetween 2 and 9 which may be due to the formation ofsurface hydrogen bonds between the hydroxyl groups on theraw RDP surface and the nitrogen atoms of RBB as sug-gested in Figure 15 +e large number and array of car-boxylic and hydroxyl groups on the RDP surface impliedexistence of many types of RDP-RBB interaction Moreoverin the desorption studies the adsorption of RBB onto theraw RDP resulted in formation of an instable chemical bondbetween the raw RDP surface and the RBB molecules whichfavored the dye molecules from being eluted from the rawRDP surface However higher amount of RBB moleculeswas eluted (sim60) +e electrostatic attraction between RBBand RDP enhances the adsorption phenomenon whichleads adsorbent more suitable to adsorb the dye [72]

5 Effect of Ionic Strength

+e ionic strength caused by the presence of salts in solutionis one of the factors that controls both electrostatic andnonelectrostatic interactions between the adsorbate and theadsorbent surface [73] In this study NaCl and BaCl2 (01 to

42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2

DubininndashRadushkevich

Figure 12 D-R isotherm plot

Table 2 D-R isotherm constants

D-R isothermE (kJmol) qm (mgg) KDR R2

154 9021 051 0472


05M) are used to increase the ionic strength of the RBBsolution Figure 16 illustrates that the concentrations of05M NaCl and 05M BaCl2 are sufficient to achieve thesemaximums of adsorption for example an initial concen-tration of RBB 40mgL As it can be observed in Figure 16an increase in the adsorption capacity is more for BaCl2 thanNaCl compared with the adsorption of RBB without salts+is result could be justified by the fact that BaCl2 is a porterof more positive charges than NaCl on the surface of rawRDP [56] Overall the improvement of removal of RBB with

increasing ionic strength can be explained by the increase inthe positive charges on the surface of the adsorbent +us itincreases the electrostatic interaction between the RBB and

Table 3 Kinetic constants of the pseudo-first-order model

Initial concentration (mgL) Experimental qe (mgg) k1 (minminus1) +eoretical qe (mgg) R2

10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)

Figure 13 Pseudo-first-order kinetic of the RBB adsorption on RDP (a) and pseudo-second-order kinetic of the RBB adsorption on RDP(b)

Table 4 Kinetic constants of the second-first-order model

Initialconcentration(mgL)

Experimentalqe (mgg)

K2 (gmolmiddotmin)

+eoreticalqe (mgg) R2

10 715 31310minus3 7633 099020 7637 36110minus3 8196 099430 7937 32310minus3 833 099540 8987 16610minus3 9708 097850 968 15310minus3 10526 098260 1055 13710minus3 11363 0980

00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)

Figure 14 Plot of Ln KC vs 1T


RDP surfaces Similar observation was found [34] during theremoval of RBB by cross-linked chitosan resins using onlyNaCl

6 Desorption Cycles of Regeneration andInterest of Using Raw RDP

+is study aims at evaluating the adsorption rate of RBBand his desorption or the regeneration rate of the bio-material adsorbent +is contribution gives an idea aboutthe overall cost of the treatment process All experimentswere carried out after saturation of RDP at 15 gL withan initial solution RBB of 40 mgL Desorption experi-ments were conducted with different eluents such asdistilled water NaOH HCl ethanol and acetone Fig-ure 17 shows that acetone has given significant results ofdesorption According to the obtained results no in-teresting desorption is observed in the acidic mediumHowever in the presence of NaOH the desorption ofRBB is approximately 37 successively +is behavior isrelated to the anionic nature of RBB and to the ionexchange and the functional groups content on thesurface of the adsorbent +e adsorption-desorptioncycles with 1 1 acetone water (vv) were used as optimumsolvent during the regeneration experiment Figure 18shows that the regeneration of RDP is possible but notsatisfactorily due to the loss of adsorbent material per-formance [74] +is phenomenon is commonly explainedby the loss of active sites on the surface of the adsorbent[75]

Separation

Drying

GrindingSieving

Figure 15 Illustration of RBB dye interaction with RDP adsorbent

Table 5 +ermodynamic parameters of RBB adsorption onto theRDP

(K) ΔHdeg(kJmiddotmolminus1) ΔSdeg (kJmiddotmolminus1middotKminus1) ΔGdeg (kJmiddotmolminus1)298

9232 0048

minus5007308 minus5552318 minus6032328 minus6512

00 01 02 03 04 050

50

100

150

200

q (m

gg)

Concentration (molL)

NaClBaCl2

Figure 16 Effect of ionic strength on the removal of RBB ontoRDP


7 Comparison of the Treatment Efficiency withLiterature Studies

+e efficiency of the adsorption capacity towards differentdyes according to the literature studies is presented inTable 6 [76ndash78] in which we have included the results ofthe present work and the conditions for establishingcomparisons As it can be seen in Table 6 the differentbiomaterials are used for the adsorption of RBB +epresent work shows an important adsorption capacityduring a fast contact time of 50min ConsequentlyMoroccan RDP could be a promising bioadsorbent for theelimination of dyes in aqueous solutions

8 Conclusion

RDP compared to various bioadsorbents has the potential inremoving RBB from aqueous solutions +e experimentalresults have shown that the absorption maximum is ob-tained at initial RBB concentration 40mgL pH 2 equi-librium contact time 50min temperature 328K particlediameter 40 microm and RDP mass 15 gL Increasing the ionicstrength of the dye solution with 05M BaCl2 enhances theadsorption capacity till 198mgg Experimental data wereadequately interpreted by Langmuir isotherm and pseudo-second-order kinetics +erefore RDP has proved effec-tiveness to remove RBB from solution In addition to theadvantage of its availability in large quantity inMauritania itpresents an eco-friendly alternative to traditional processesof textile wastewater treatment even though the test ofadsorption-desorption cycles demonstrates that the bio-adsorbent cannot be used several times and it is still a cost-effective bioadsorbent taking into account the high ad-sorption yield reached Moreover exploring the feasibility ofusing the RDP before and after thermic treatment could bean important perspective for future work

Data Availability

All data underlying the findings of this study are fullyavailable without restriction

Conflicts of Interest

+e authors declare that they have no conflicts of interest

Acknowledgments

+e authors thank the general services (SEM XRD andInfrared) of the innovation center University of Fez(Morocco)

References

[1] F Mejbar Y Miyah A El Badraoui et al ldquoStudies of theadsorption kinetics process for removal of methylene blue dyeby residue of grenadine bark extractionrdquoMoroccan Journal ofChemistry vol 6 pp 436ndash443 2019

[2] N Loubna Y Miyah O Assila A El Badraoui B El Khazzanand F Zerrouq ldquoKinetic and thermodynamicstudy of theadsorption of twodyes brilliant green and eriochrome black Tusing a natural adsorbent ldquosugarcane bagasserdquordquo MoroccanJournal of Chemistryvol 7 pp 715ndash726 2019

0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H

Figure 17 Desorption of RBB using different eluents

1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle

AdsorptionDesorption

Figure 18 Desorption of RBB using 50 acetone after 4 cycles

Table 6 Comparison of the treatment efficiency with literaturestudies

Adsorbent Dyes Adsorptioncapacities (mgg)

Contacttime (min) Reference

RDP RBB 105 50 +is workPineapple leafpowder RBB 962 900 [76]

Salvinianatans RBB 619 800 [77]

Orange peel RBB 97 900 [78]


[3] M A Al-ghouti J Li Y Salamh N Al-laqtah GWalker andM N M Ahmad ldquoAdsorption mechanisms of removingheavy metals and dyes from aqueous solution using date pitssolid adsorbentrdquo Journal of Hazardous Materials vol 176no 1-3 pp 510ndash520 2010

[4] K M Kifuani A Kifuani Kia Mayeko P Noki Vesitulutaet al ldquoAdsorption drsquoun colorant basique Bleu de Methyleneen solution aqueuse sur un bioadsorbant issu de dechetsagricoles derdquo International Journal of Biological and ChemicalSciences vol 12 2018

[5] F Alakhras E Alhajri R Haounati H Ouachtak A A Addiand T A Saleh ldquoA comparative study of photocatalyticdegradation of rhodamine B using natural-based zeolitecompositesrdquo Surfaces and Interfaces vol 20 2020

[6] Z Bencheqroun Z Chaouki M Hadri et al ldquoRemoval oftextile dyes from aqueous solutions using low cost Moroccanclayrdquo IOP Conference Series Earth and Environmental Sci-ence vol 161 2018

[7] A A Basaleh M H Al-Malack and T A Saleh ldquoMethyleneBlue removal using polyamide-vermiculite nanocompositeskinetics equilibrium and thermodynamic studyrdquo Journal ofEnvironmental Chemical Engineering vol 7 no 3 p 1031072019

[8] M Alipour M Vosoughi S A Mokhtari et al ldquoOptimisingthe basic violet 16 adsorption from aqueous solutions bymagnetic graphene oxide using the response surface modelbased on the Box-Behnken designrdquo International Journal ofEnvironmental Analytical Chemistry pp 1ndash20 2019

[9] R Ahmad and R Kumar ldquoAdsorptive removal of Congo reddye from aqueous solution using bael shell carbonrdquo AppliedSurface Science vol 257 no 5 pp 1628ndash1633 2010

[10] L Bulgariu L B Escudero O S Bello et al ldquo+e utilization ofleaf-based adsorbents for dyes removal a reviewrdquo Journal ofMolecular Liquids vol 276 pp 728ndash747 2019

[11] H N Bhatti A Jabeen M Iqbal S Noreen and Z NaseemldquoAdsorptive behavior of rice bran-based composites formalachite green dye isotherm kinetic and thermodynamicstudiesrdquo Journal of Molecular Liquids vol 237 pp 322ndash3332017

[12] M Ahmad G Abbas R Haider et al ldquoKinetics and equi-librium studies of eriobotrya japonica a novel adsorbentpreparation for dyes sequestrationrdquo Zeitschrift fur Phys-ikalische Chemie vol 233 no 10 pp 1ndash16 2018

[13] S Ledakowicz M Solecka and R Zylla ldquoBiodegradationdecolourisation and detoxification of textile wastewater en-hanced by advanced oxidation processesrdquo Journal of Bio-technology vol 89 no 2-3 pp 175ndash184 2001

[14] F Zhou Y Cheng L Gan Z Chen M Megharaj andR Naidu ldquoBurkholderia vietnamiensis C09V as the functionalbiomaterial used to remove crystal violet and Cu(II)rdquo Eco-toxicology and Environmental Safety vol 105 pp 1ndash6 2014

[15] K Tanji J A Navio A Chaqroune et al ldquoFast photo-degradation of rhodamine B and caffeine using ZnO-hy-droxyapatite composites under UV-light illuminationrdquoCatalysis Today 2020

[16] M Zouhier K Tanji J A Navio M C Hidalgo C Jaramillo-Paez and A Kherbeche ldquoPreparation of ZnFe2O4ZnOcomposite effect of operational parameters for photocatalyticdegradation of dyes under UV and visible illuminationrdquoJournal of Photochemistry and Photobiology A Chemistryvol 390 2020

[17] K Tanji J A Navio A N Martın-Gomez et al ldquoRole ofFe(III) in aqueous solution or deposited on ZnO surface in the

photoassisted degradation of rhodamine B and caffeinerdquoChemosphere vol 241 2019

[18] K Tanji J A Navio J Naja et al ldquoExtraordinary visiblephotocatalytic activity of a Co02Zn08O system studied in theRemazol BB oxidationrdquo Journal of Photochemistry andPhotobiology A Chemistry vol 382 p 111877 2019

[19] N Javid Z Honarmandrad and M Malakootian ldquoCipro-floxacin removal from aqueous solutions by ozonation withcalcium peroxiderdquo Desalination and Water Treatmentvol 174 pp 178ndash185 2020

[20] Z Honarmandrad N Javid and M Malakootian ldquoEfficiencyof ozonation process with calcium peroxide in removingheavy metals (Pb Cu Zn Ni Cd) from aqueous solutionsrdquoSN Applied Sciences vol 2 no 4 pp 1ndash7 2020

[21] A Ait hssi E Amaterz N labchir et al ldquoElectrodepositedZnO nanorods as efficient photoanodes for the degradation ofrhodamine Brdquo Physica Status Solidi vol 217 no 17 2020

[22] E Amaterz A Tara A Bouddouch et al ldquoHierarchicalflower-like SrHPO4 electrodes for the photoelectrochemicaldegradation of Rhodamine Brdquo Journal of Applied Electro-chemistry vol 50 no 5 pp 569ndash581 2020

[23] K B Tan M Vakili B A Horri P E Poh A Z Abdullahand B Salamatinia ldquoAdsorption of dyes by nanomaterialsrecent developments and adsorption mechanismsrdquo Separa-tion and Purification Technology vol 150 pp 229ndash242 2015

[24] M M Al-arsquoqarbeh M W Shammout and A M AwwadldquoNano platelets kaolinite for the adsorption of toxic metal ionsin the environmentrdquo International Journal of Chemistryvol 6 2020

[25] A M Alasadi F I Khaili and A M Awwad ldquoAdsorption ofCu ( II ) Ni ( II ) and Zn ( II ) ions by nano kaolinite thermodynamics and kinetics studiesrdquo International Journalof Chemistry vol 5 pp 258ndash268 2019

[26] A Farsi N Javid and M Malakootian ldquoInvestigation ofadsorption efficiency of Cu2+ and Zn2+ by red soil andactivated bentonite from acid copper mine drainagerdquo Desa-lination and Water Treatment vol 144 pp 172ndash184 2019

[27] M Mahmoodi Meimand N Javid and M MalakootianldquoAdsorption of sulfur dioxide on clinoptilolitenano ironoxide and natural clinoptiloliterdquo Health Scope vol 8 ArticleID e69158 2019

[28] A Hamzezadeh Y Rashtbari S Afshin M Morovati andM Vosoughi ldquoApplication of low-cost material for adsorp-tion of dye from aqueous solutionrdquo International Journal ofEnvironmental Analytical Chemistry pp 1ndash16 2020

[29] M Fazal-ur-rehman ldquoCurrent scenario and future prospectsof activated carbon preparation from agro- industrial wastes a reviewrdquo International Journal of Chemistry vol 4pp 109ndash119 2018

[30] A M Alkherraz A K Ali and K M Elsherif ldquoRemoval of Pb(II) Zn (II) Cu (II) and Cd (II) from aqueous solutions byadsorption onto olive branches activated carbon equilibriumand thermodynamic studiesrdquo International Journal ofChemistry vol 6 pp 11ndash20 2020

[31] F Sakr A Sennaoui M Elouardi M Tamimi andA Assabbane ldquoEtude de lrsquoadsorption du Bleu de Methylenesur un biomateriau a base deCactus (Adsorption study ofMethylene Blue on biomaterial using cactus)rdquo Journal ofMaterials and Environmental Science vol 6 pp 397ndash4062015

[32] Y Miyah M Idrissi and F Zerrouq ldquoEtude et Modelisationde la Cinetique drsquoAdsorption du Bleu de Methylene sur lesAdsorbants Argileux (Pyrophillite Calcite) Study and Mod-eling of the Kinetics Methylene blue Adsorption on the Clay


Adsorbents (Pyrophillite Calcite)rdquo Journal of Materials andEnvironmental Science vol 6 pp 699ndash712 2015

[33] K K H Choy G McKay and J F Porter ldquoSorption of aciddyes from effluents using activated carbonrdquo ResourcesConservation and Recycling vol 27 no 1-2 pp 57ndash71 1999

[34] L-X Zeng Y-F Chen Q-Y Zhang Y Kang and J-W LuoldquoAdsorption of Congo red by cross-linked chitosan resinsrdquoDesalination and Water Treatment vol 52 no 40-42pp 7733ndash7742 2014

[35] Z Zhang W Wang Y Kang L Zong and A Wang ldquoTai-loring the properties of palygorskite by various organic acidsvia a one-pot hydrothermal process a comparative study forremoval of toxic dyesrdquo Applied Clay Science vol 120pp 28ndash39 2016

[36] O Assila K Tanji M Zouheir et al ldquoAdsorption studies onthe removal of textile effluent over two natural eco-friendlyadsorbentsrdquo Journal of Chemistry vol 2020 Article ID6457825 13 pages 2020

[37] R Haounati O Hassan H RachidEl et al ldquoElaboration andproperties of a new SDSCTABMontmorillonite organoclaycompositeas a superb adsorbent for the removal of malachitegreen from aqueous solutionsrdquo Separation and PurificationTechnology vol 255 Article ID 117335 2020

[38] R-R Shan L-G Yan Y-M Yang et al ldquoHighly efficientremoval of three red dyes by adsorption onto Mg-Al-layereddouble hydroxiderdquo Journal of Industrial and EngineeringChemistry vol 21 pp 561ndash568 2015

[39] S Chakma and V S Moholkar ldquoSynthesis of bi-metallicoxides nanotubes for fast removal of dye using adsorption andsonocatalysis processrdquo Journal of Industrial and EngineeringChemistry vol 37 pp 84ndash89 2016

[40] H Ouachtak S Akhouairi R Haounati et al ldquo34-Dihy-droxybenzoic acid removal from water by goethite modifiednatural sand column fixed-bed experimental study andmathematical modelingrdquo Desalination and Water Treatmentvol 194 pp 439ndash449 2020

[41] A Dra A El Gaidoumi K Tanji A Chaouni BenabdallahA Taleb and A Kherbeche ldquoCharacterization and quanti-fication of heavy metals in oued sebou sedimentsrdquo e Sci-entific World Journal vol 2019 2019

[42] A Dra K Tanji A Arrahli et al ldquoValorization of oued sebounatural sediments (Fez-Morocco area) as adsorbent ofmethylene blue dye kinetic and thermodynamic studyrdquo eScientific World Journal vol 2020 pp 1ndash8 2020

[43] M Arami N Y Limaee N M Mahmoodi and N S TabrizildquoRemoval of dyes from colored textile wastewater by orangepeel adsorbent equilibrium and kinetic studiesrdquo Journal ofColloid and Interface Science vol 288 no 2 pp 371ndash3762005

[44] M S Rahman S Kasapis N S Z Al-Kharusi I M Al-Marhubi and A J Khan ldquoComposition characterisation andthermal transition of date pits powdersrdquo Journal of FoodEngineering vol 80 no 1 pp 1ndash10 2007

[45] N Javid and M Malakootian ldquoRemoval of bisphenol a fromaqueous solutions by modified-carbonized date pits by znonano-particlesrdquo Desalination and Water Treatment vol 95pp 144ndash151 2017

[46] N Javid A Nasiri and M Malakootian ldquoRemoval of non-ylphenol from aqueous solutions using carbonized date pitsmodified with ZnO nanoparticlesrdquo Desalination and WaterTreatment vol 141 pp 140ndash148 2019

[47] N Kannan and M Meenakshisundaram ldquoAdsorption ofCongo red on various activated carbonsrdquoWater Air and SoilPollution vol 138 pp 289ndash305 2002

[48] P Senthil Kumar S Ramalingam C SenthamaraiM Niranjanaa P Vijayalakshmi and S Sivanesan ldquoAd-sorption of dye from aqueous solution by cashew nut shellstudies on equilibrium isotherm kinetics and thermody-namics of interactionsrdquo Desalination vol 261 no 1-2pp 52ndash60 2010

[49] C Bouchelta M S Medjram O Bertrand and J-P BellatldquoPreparation and characterization of activated carbon fromdate stones by physical activation with steamrdquo Journal ofAnalytical and Applied Pyrolysis vol 82 no 1 pp 70ndash772008

[50] H M Al-Saidi ldquo+e fast recovery of gold(III) ions fromaqueous solutions using raw date pits kinetic thermody-namic and equilibrium studiesrdquo Journal of Saudi ChemicalSociety vol 20 no 6 pp 615ndash624 2016

[51] S M Yakout and G Sharaf El-Deen ldquoCharacterization ofactivated carbon prepared by phosphoric acid activation ofolive stonesrdquo Arabian Journal of Chemistry vol 9pp S1155ndashS1162 2016

[52] A-N A El-Hendawy ldquoVariation in the FTIR spectra of abiomass under impregnation carbonization and oxidationconditionsrdquo Journal of Analytical and Applied Pyrolysisvol 75 no 2 pp 159ndash166 2006

[53] R El Haouti H Ouachtak A El Guerdaoui et al ldquoCationicdyes adsorption by Na-Montmorillonite Nano Clay experi-mental study combined with a theoretical investigation usingDFT-based descriptors and molecular dynamics simulationsrdquoJournal of Molecular Liquids vol 290 2019

[54] A M M Vargas A L Cazetta M H Kunita T L Silva andV C Almeida ldquoAdsorption of methylene blue on activatedcarbon produced from flamboyant pods (Delonix regia)study of adsorption isotherms and kinetic modelsrdquo ChemicalEngineering Journal vol 168 no 2 pp 722ndash730 2011

[55] M Arulkumar P Sathishkumar and T Palvannan ldquoOpti-mization of Orange G dye adsorption by activated carbon ofespesia populnea pods using response surface methodol-ogyrdquo Journal of Hazardous Materials vol 186 no 1pp 827ndash834 2011

[56] R Hachani H Sabir N Sana K F Zohra and N M NesrineldquoPerformance study of a low-cost adsorbent-raw date pits-forremoval of azo dye in aqueous solutionrdquo Water EnvironmentResearch vol 89 no 9 pp 827ndash839 2017

[57] A Tor and Y Cengeloglu ldquoRemoval of Congo red fromaqueous solution by adsorption onto acid activated red mudrdquoJournal of Hazardous Materials vol 138 no 2 pp 409ndash4152006

[58] M El Marouani K Azoulay I Bencheikh et al ldquoApplicationof raw and roasted date seeds for dyes removal from aqueoussolutionrdquo Journal of Materials and Environmental Sciencevol 9 pp 2387ndash2396 2018

[59] A Saeed M Sharif and M Iqbal ldquoApplication potential ofgrapefruit peel as dye sorbent kinetics equilibrium andmechanism of crystal violet adsorptionrdquo Journal of HazardousMaterials vol 179 no 1-3 pp 564ndash572 2010

[60] E Lorenc-Grabowska and G Gryglewicz ldquoAdsorptioncharacteristics of Congo red on coal-based mesoporous ac-tivated carbonrdquo Dye Pigment vol 74 no 1 pp 34ndash40 2006

[61] M Ozacar and I A Sengil ldquoEquilibrium data and processdesign for adsorption of disperse dyes onto Aluniterdquo Envi-ronmental Geology vol 45 pp 762ndash768 2004

[62] A Seidmohammadi G Asgari A Dargahi et al ldquoA com-parative study for the removal of Methylene blue dye fromaqueous solution by novel activated Carbon based


adsorbentsrdquo Progress in Color Colorants and Coatings vol 12pp 133ndash144 2019

[63] L-F Chen H-H Wang K-Y Lin J-Y Kuo M-K Wangand C-C Liu ldquoRemoval of methylene blue from aqueoussolution using sediment obtained from a canal in an industrialparkrdquo Water Science and Technology vol 78 no 3pp 556ndash570 2018

[64] B Acemioǧlu ldquoAdsorption of Congo red from aqueous so-lution onto calcium-rich fly ashrdquo Journal of Colloid and In-terface Science vol 274 no 2 pp 371ndash379 2004

[65] M Mohamed and S Ouki ldquoRemoval mechanisms of toluenefrom aqueous solutions by chitin and chitosanrdquo Industrial ampEngineering Chemistry Research vol 50 no 16 pp 9557ndash9563 2011

[66] M A Al-Ghouti A Hawari and M Khraisheh ldquoA solid-phase extractant based on microemulsion modified date pitsfor toxic pollutantsrdquo Journal of Environmental Managementvol 130 pp 80ndash89 2013

[67] O Khelifi I Mehrez W Ben Salah et al ldquoEtude de lrsquoad-sorption du bleu de methylene (BM) a partir des solutionsaqueuses sur un biosorbant prepare a partir des noyaux dedatte algeriennerdquo Larhyss Journal vol 28 pp 135ndash148 2016

[68] F Abed and K Louhab ldquoAdsorption of methylene blue (MB)from aqueous solution using mixed sorbents prepared fromdate pit and olive stonerdquo International Letters of ChemistryPhysics and Astronomy vol 51 pp 94ndash104 2015

[69] S Afshin S A Mokhtari M Vosoughi H Sadeghi andY Rashtbari ldquoData of adsorption of Basic Blue 41 dye fromaqueous solutions by activated carbon prepared from fila-mentous algaerdquo Data in Brief vol 21 pp 1008ndash1013 2018

[70] K Mahmoudi K Hosni N Hamdi and E Srasra ldquoKineticsand equilibrium studies on removal of methylene blue andmethyl orange by adsorption onto activated carbon preparedfrom date pits-A comparative studyrdquo Korean Journal ofChemical Engineering vol 32 no 2 pp 274ndash283 2014

[71] C Namasivayam and D Kavitha ldquoRemoval of Congo Redfrom water by adsorption onto activated carbon preparedfrom coir pith an agricultural solid wasterdquo Dyes and Pig-ments vol 54 no 1 pp 47ndash58 2002

[72] K Imamura E Ikeda T Nagayasu T Sakiyama andK Nakanishi ldquoAdsorption behavior of methylene blue and itscongeners on a stainless steel surfacerdquo Journal of Colloid andInterface Science vol 245 no 1 pp 50ndash57 2002

[73] C Moreno-Castilla and J Rivera-Utrilla ldquoCarbonmaterials asadsorbents for the removal of pollutants from the aqueousphaserdquo MRS Bulletin vol 26 no 11 pp 890ndash894 2001

[74] V K Gupta and A Rastogi ldquoBiosorption of hexavalentchromium by raw and acid-treated green alga Oedogoniumhatei from aqueous solutionsrdquo Journal of Hazardous Mate-rials vol 163 no 1 pp 396ndash402 2009

[75] S Hazourli G Bonnecaze and M Astruc ldquoAdsorption etElectrosorption de Composes Organiques Sur Charbon Actifen Grains Partie I - influence du Potentiel Impose et duNombre de Cycles Adsorption and Electrosorption of OrganicCompounds on Granular Activated Carbon Part I - influenceof Applied Potential and Number of Cyclesrdquo EnvironmentalTechnology vol 17 no 12 pp 1275ndash1283 1996

[76] N A Rahmat A A Ali Salmiati et al ldquoRemoval of remazolbrilliant blue R from aqueous solution by adsorption usingpineapple leaf powder and lime peel powderrdquo Water Air ampSoil Pollution vol 227 no 4 2016

[77] B T Pelosi L K S Lima and M G A Vieira ldquoRemoval ofthe synthetic dye remazol brilliant blue r from textile industrywastewaters by biosorption on the macrophyte Salvinia

natansrdquo Brazilian Journal of Chemical Engineering vol 31no 4 pp 1035ndash1045 2014

[78] M R Mafra L Igarashi-Mafra D R Zuim E C Vasquesand M A Ferreira ldquoAdsorption of remazol brilliant blue onan orange peel adsorbentrdquo Brazilian Journal of ChemicalEngineering vol 30 no 3 pp 657ndash665 2013


investigated for the removal of dyes in recent years [35] suchas clay [36 37] layered double hydroxides [38] metal oxides[39] goethite modified natural [40] and sediments [41 42]+e activated carbon has a high cost Hence the need to lookfor cheaper effective and natural available adsorbent istherefore interesting [43] Bioadsorbent materials have beenproposed as alternative adsorbents for dyes EspeciallyRDPs have received considerable attention for its propertiessuch as low cost natural availability and no threat to theenvironment +e fruit of the date palm is composed of afleshy pericarp and seed Pits of date palm (seed) are a wasteproduct of many date fruit-processing plants producingpitted dates date powders date syrup date juice chocolate-coated dates and date confectionery [44] In addition theRDP are very widely distributed and abundant which makethem the promising environmental adsorbents that can beused in industrial processes [3] Javid et al have studied theremoval of bisphenol A and nonylphenol from aqueoussolutions using carbonized date pits modified with ZnOnanoparticles and they found maximum removal efficiencyunder optimal conditions was 95 [45 46] However ad-sorption of RBB onto the RDP was not fully investigated[43]+erefore the objective of this work is to investigate thephysics and chemical properties of RDP bioadsorbent usingmultiple methods such as X-ray diffraction (XRD) scanningelectron microscopy (SEM) and Fourier-transform infraredspectroscopy (FTIR) and then to evaluate the effectiveness ofusing RDP as natural eco-friendly and low-cost bio-adsorbent for the removal of RBB in aqueous mediaMoreover various parameters influencing the adsorptionprocedure of RBB adsorption on the RDP bioadsorbentsuch as the adsorbent mass solution pH RDP particle sizeand RBB initial concentration were studied On the otherhand the ionic strength effect using BaCl2 on the adsorptionequilibrium is important to highlight as well

2 Materials and Methods

21 Preparation of RDP Moroccan dates were shelled andthe pits were collected and sorted in order to remove theimpurities and then dried at a temperature of 110degC in theoven for 24 hours +en the bioadsorbent was ground in agrinder and sieved in order to obtain particles of the samesize with a diameter of 40 63 125 and 200 microm RDPcontains an approximate percentage of hemicellulose lignincellulose and carbohydrates [3]

22 Adsorbate +e dye considered in this study is RemazolBrilliant Blue (RBB) analytical grade purchased for Sigma-Aldrich it has the chemical formula C22H16N2Na2O11S3and its maximum absorption band is located at the wave-length of 590 nm +e main problems associated with RBBdye in textile wastewaters are resistant to biodegradationhighly visible due to its bright color even in very lowconcentration of dye (lt1mgL) in the effluent and verytoxic difficult to remove by traditional methods

23 Adsorption Study In this study a stock solution wasprepared from the RBB dye +e adsorption study was

carried out by using 1 g of RDPmixed with a solution of RBBat room temperature under continuous stirring in a batchsystem In order to investigate the kinetic adsorption severalsamples were collected each 5min to measure its concen-tration using UV-visible spectrophotometer (VR-2000) at awavelength of 590 nm Nevertheless before the measure thesuspension was centrifuged to separate the natural adsorbentfrom the RBB liquid During the adsorption experimentHCl (05M) and NaOH (05M) from Sigma-Aldrich wereused to adjust the pH solution

+e RBB removal was calculated using following formula[43 47]

removal() C0 minus Ct( 1113857

C0times 100 (1)

where C0 and Ct are the concentration of RBB at t 0 and attne0 respectively

+e adsorption capacity of RDP for RBB removal wasobtained by applying the following equation [48]

qe C0 minus Ce( 1113857

mtimes V (2)

where qe (mgg) is the adsorption capacity at equilibrium C0(mgL) is the initial concentration of RBB Ce (mgL) is theequilibrium concentration of RBB V (L) is the RBB solutionvolume and m (g) is the RDP mass

24 Characterization Techniques +e X-ray diffraction (XprimePERT PRO) equipped with a detector operating at 40 kV and30mA with Cu Kα radiation (λ1540598 A) infraredspectroscopy (VERTEX 70) and scanning electron mi-croscopy (QUANTA 200) were used to identify the com-position and the morphology of adsorbents materials toexplore the chemical composition of RDP

3 Results and Discussion

31 RDP Characterization

311 X-Ray Diffraction (XRD) +e X-ray pattern of RDPdata is given in Figure 1 It can be observed that dif-fractogram of bioadsorbent RDP does not exhibit a hori-zontal basic line and displayed the presence of littlediffraction peaks +e broad diffraction peak located be-tween 20deg and 25deg could be ascribed to carbon speciesaccording to the native cellulose (C6H12O6) and to xylanedehydrate (C10H12O9middot2H2O) [49]On the contrary the otherfew small diffraction peaks may be attributed to the presenceof a small amount of crystalline matter +erefore this resultindicated that the major part of the matter is amorphous

312 Scanning Electron Microscopy (SEM) SEM analysis ismade on RDP before adsorption (Figures 2(a) and 2(b))+ematerial has a smooth porous surface indicating a goodpossibility of trapping RBB adsorption on the adsorbentsurface On the contrary after the RBB is adsorbed into RDPbiomaterials the SEM observation shows the surface of RDPcharged with RBB displaying a rough and corroded surface






10 15 20 25 30 35 40 45

Inte

nsity

(au

)

2 thetadeg

Carbon


(a) (b)

(c) (d)









4000 3500 3000 2500 2000 1500 1000 500

1422

56

2856

31

2922

45

Tran

smitt

ance

()



34113416

225

6

1041

21


2 3 4 5 6 7 8 9 100

20

40

60

80

100

Rem

oval

()

pH


0 2 4 6 8 10 12 14

0

2

4

6

8

pHi

pHf








0 10 20 30 40 50 600

20

40

60

80

100

120

q max

(mg

g)

Time (min)

1015mgg

2 gL25 gL3 gL

05 gL1 gL15 gL (a)

05 10 15 20 25 30

50

55

60

65

70

75

80

85


Mass (gL)

Rem

oval

() 8255

60

70

80

90

100

qe (m

gg)

1015mgg

(b)




1qe

1

qmax+


times1

Ce

(3)



0 10 20 30 40 50 600

20

40

60

80

100

Rem

oval

()

Time (min)

40microm63microm

125microm 200microm

95


1015mgg

0 10 20 30 40 50 60Time (min)

0

20

40

60

80

100

120

q max

(mg

g)

60mgL

50mgL

40mgL

30mgL

20mgL

10mgL(a)

10 20 30 40 50 6078

80

82

84

86

88

90

92

94


Concentration (mgL)

Rem

oval

()

70

75

80

85

90

95

100

105

110

qe (m

gg)

(b)


295 300 305 310 315 320 325 3300

20

40

60

80

100

Rem

oval

()

Temperature (K)









0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)


0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)




058 2392 0890 10752 109 0991






2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle

































































































10 15 20 25 30 35 40 45

Inte

nsity

(au

)

2 thetadeg

Carbon


(a) (b)

(c) (d)









4000 3500 3000 2500 2000 1500 1000 500

1422

56

2856

31

2922

45

Tran

smitt

ance

()



34113416

225

6

1041

21


2 3 4 5 6 7 8 9 100

20

40

60

80

100

Rem

oval

()

pH


0 2 4 6 8 10 12 14

0

2

4

6

8

pHi

pHf








0 10 20 30 40 50 600

20

40

60

80

100

120

q max

(mg

g)

Time (min)

1015mgg

2 gL25 gL3 gL

05 gL1 gL15 gL (a)

05 10 15 20 25 30

50

55

60

65

70

75

80

85


Mass (gL)

Rem

oval

() 8255

60

70

80

90

100

qe (m

gg)

1015mgg

(b)




1qe

1

qmax+


times1

Ce

(3)



0 10 20 30 40 50 600

20

40

60

80

100

Rem

oval

()

Time (min)

40microm63microm

125microm 200microm

95


1015mgg

0 10 20 30 40 50 60Time (min)

0

20

40

60

80

100

120

q max

(mg

g)

60mgL

50mgL

40mgL

30mgL

20mgL

10mgL(a)

10 20 30 40 50 6078

80

82

84

86

88

90

92

94


Concentration (mgL)

Rem

oval

()

70

75

80

85

90

95

100

105

110

qe (m

gg)

(b)


295 300 305 310 315 320 325 3300

20

40

60

80

100

Rem

oval

()

Temperature (K)









0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)


0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)




058 2392 0890 10752 109 0991






2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle



































































































4000 3500 3000 2500 2000 1500 1000 500

1422

56

2856

31

2922

45

Tran

smitt

ance

()



34113416

225

6

1041

21


2 3 4 5 6 7 8 9 100

20

40

60

80

100

Rem

oval

()

pH


0 2 4 6 8 10 12 14

0

2

4

6

8

pHi

pHf








0 10 20 30 40 50 600

20

40

60

80

100

120

q max

(mg

g)

Time (min)

1015mgg

2 gL25 gL3 gL

05 gL1 gL15 gL (a)

05 10 15 20 25 30

50

55

60

65

70

75

80

85


Mass (gL)

Rem

oval

() 8255

60

70

80

90

100

qe (m

gg)

1015mgg

(b)




1qe

1

qmax+


times1

Ce

(3)



0 10 20 30 40 50 600

20

40

60

80

100

Rem

oval

()

Time (min)

40microm63microm

125microm 200microm

95


1015mgg

0 10 20 30 40 50 60Time (min)

0

20

40

60

80

100

120

q max

(mg

g)

60mgL

50mgL

40mgL

30mgL

20mgL

10mgL(a)

10 20 30 40 50 6078

80

82

84

86

88

90

92

94


Concentration (mgL)

Rem

oval

()

70

75

80

85

90

95

100

105

110

qe (m

gg)

(b)


295 300 305 310 315 320 325 3300

20

40

60

80

100

Rem

oval

()

Temperature (K)









0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)


0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)




058 2392 0890 10752 109 0991






2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle


































































































0 10 20 30 40 50 600

20

40

60

80

100

120

q max

(mg

g)

Time (min)

1015mgg

2 gL25 gL3 gL

05 gL1 gL15 gL (a)

05 10 15 20 25 30

50

55

60

65

70

75

80

85


Mass (gL)

Rem

oval

() 8255

60

70

80

90

100

qe (m

gg)

1015mgg

(b)




1qe

1

qmax+


times1

Ce

(3)



0 10 20 30 40 50 600

20

40

60

80

100

Rem

oval

()

Time (min)

40microm63microm

125microm 200microm

95


1015mgg

0 10 20 30 40 50 60Time (min)

0

20

40

60

80

100

120

q max

(mg

g)

60mgL

50mgL

40mgL

30mgL

20mgL

10mgL(a)

10 20 30 40 50 6078

80

82

84

86

88

90

92

94


Concentration (mgL)

Rem

oval

()

70

75

80

85

90

95

100

105

110

qe (m

gg)

(b)


295 300 305 310 315 320 325 3300

20

40

60

80

100

Rem

oval

()

Temperature (K)









0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)


0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)




058 2392 0890 10752 109 0991






2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle






























































































1qe

1

qmax+


times1

Ce

(3)



0 10 20 30 40 50 600

20

40

60

80

100

Rem

oval

()

Time (min)

40microm63microm

125microm 200microm

95


1015mgg

0 10 20 30 40 50 60Time (min)

0

20

40

60

80

100

120

q max

(mg

g)

60mgL

50mgL

40mgL

30mgL

20mgL

10mgL(a)

10 20 30 40 50 6078

80

82

84

86

88

90

92

94


Concentration (mgL)

Rem

oval

()

70

75

80

85

90

95

100

105

110

qe (m

gg)

(b)


295 300 305 310 315 320 325 3300

20

40

60

80

100

Rem

oval

()

Temperature (K)









0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)


0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)




058 2392 0890 10752 109 0991






2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle



































































































0 10 20 30 40 50 600

20

40

60

80

100

120

q (m

gg)

Time (min)


0 2 4 6 8 10 12 14 16000

002

004

006

008

010

012

014

C eq

e (g

L)

Ce (mgL)

(a)

ndash02 00 02 04 06 08 10 12184

186

188

190

192

194

196

198

200

202

204Lo

g (q

e)

Log (Ce)

(b)




058 2392 0890 10752 109 0991






2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle

































































































2303t (6)

t

q

1k2 q

2e

+t

q (7)





LnKLdeg ΔSdeg

R1113888 1113889 minus

ΔHdeg

RT1113888 1113889


(8)







42 43 44 45 46 47

0

1

2

3

4

5

Ln (qe)

e2 (Jm

ol)2





154 9021 051 0472






10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle

































































































10 715 0069 9102 097020 7637 0110 1015 097230 7937 0152 18493 069140 8987 0163 1924 071850 968 0013 6957 074060 1055 0082 1253 0911

10 20 30 40 50 60ndash8

ndash6

ndash4

ndash2

0

2

6

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Ln (q

endashq t

)

Time (min)

4

(a)

00

02

04

06

08

10

tqt

100 20 30 40 50 60

10mgL

20mgL

30mgL

40mgL

50mgL

60mgL

Time (min)

(b)





K2 (gmolmiddotmin)



00030 00031 00032 00033 00034

200

205

210

215

220

225

230

235

240

LnKc

1T (Kndash1)






Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle
































































































Separation

Drying

GrindingSieving




9232 0048


00 01 02 03 04 050

50

100

150

200

q (m

gg)


NaClBaCl2





8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle































































































8 Conclusion


Data Availability




Acknowledgments


References



0

20

40

60

80

100

50

acet

one

50

etha

nol

01M HCl

Des

orpt

ion

()

Water

01M

NaO

H


1 2 3 40

20

40

60

80

100

Ads

orpt

ion-

deso

rptio

n (

)

Cycle






















































































































































































































































Documents

ValorizationofDatePitsasanEffectiveBiosorbentforRemazol ...downloads.hindawi.com/journals/jchem/2020/4173152.pdf · ResearchArticle ValorizationofDatePitsasanEffectiveBiosorbentforRemazol