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Georgi Zhelyazkov (Bulgaria)

2011

Volume 3, Number 4December 2011

Online Version ISSN: 1314-412X

Study on the applicability of a natural geomaterial for mononitrophenol removal from simulated agricultural run-off water

1 2 1Z. Yaneva *, B. Koumanova , N. Georgieva

1Department of Pharmacology, Animal Physiology and Physiological Chemistry, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria 2Department of Chemical Engineering, University of Chemical Technology and Metallurgy, 8 Kliment Ohridski, 1756 Sofia, Bulgaria

Abstract. The widespread use of pesticides and herbicides in agricultural areas worldwide has led to serious potential for pollution problems of the soils, surface and groundwaters in the adjacent terrains. The purpose of this study was to evaluate the ability of the geomaterial expanded perlite to remove xenobiotic organic compounds from polluted water introduced by agricultural and other activities. The model compound selected in this study was o-nitrophenol, a chemical commonly used in the manufacture of pesticides. The experimental equilibrium data were interpreted from Langmuir and Freundlich isotherm models. The applicability of both models was assessed on the basis of the calculated model parameters and correlation coefficients. The statistical significance of the results was tested on the basis of the SSE and RMSE values. The satisfactory efficiency (70 % removal) of the applied method proved its potential for large-scale applications.

Keywords: o-nitrophenol, expanded perlite, agricultural run-off water, sorption

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 3, No 4, pp 354 - 358, 2011

groundwater, contaminant attenuation during riverbank filtration, or Introductioncontaminant transport with seepage water are frequently affected by geosorption (Rahman and Worch, 2005).

Nitroaromatic pesticides such as dinoseb, dinitrocresol, During the last decade, the scientific efforts have been directed parathion and methyl parathion have been extensively used in towards the use of economically expedient and easily available agriculture, leading to accumulation of nitrophenols in the soil natural materials as efficient sorbents for toxic organic removal from (Labana et al., 2005). According to recent studies nitrophenols in aqueous phase. Perlite is a natural occurring dense glassy volcanic surface waters and surface soils are readily degraded by ryholitic rock that can be expanded up to 20 times its original volume

ophotochemical oxidation. However, in deeper soils and when heated rapidly at 800–1200 C. The expanded perlite is white in 3groundwater, nitrophenol degradation depends primarily on color, and has a density of about 32 kg/m . Perlite is generally

biodegradation. The biodegradation of nitroaromatics can be chemically inert and has a pH of approximately 7. It is very cheap and initiated by either reductive or oxidative mechanisms (Wang et al., easily available. Expanded perlite acts as an excellent insulator, 2005). Nitrophenols are considered as priority pollutants since they both thermal and acoustical, resists fire and is classified as an ultra-are harmful to organisms at low concentrations and many of them light weight material (Govindasamy et al., 2009; Ghassabzadeh et have been classified as hazardous pollutants because of their al., 2010; Torab-Mostaedi et al., 2010). For commercial use it is potential to harm human health. Because of their toxicity, these exposed to an exfoliation process at high temperatures that kills organic compounds have been included in the of US Environmental microorganisms. However, if necessary, it can be easily sterilized Protection Agency (EPA) list of priority pollutants (US EPA, 1987). with no risk of producing toxic substances (Daza et al., 2000). Thus, it is necessary to eliminate them from the soil, natural Unexpanded perlite has been used as a filter aid in industrial surface/groundwaters or wastewaters before their discharge processes. In horticultural applications, perlite is used as a (Calace et al., 2002). Other sources of nitrophenols in the component of soil-less growing mixes where it provides aeration and environment are effluents from mine processing facilities, foundries, optimum moisture retention for superior plant growth. Other benefits metal finishing plants, refineries, dye manufacturing plants, of horticultural perlite are its neutral pH and the fact that it is sterile explosives and, etc (Al-Mutairi, 2010). In an aquatic compartment and weed-free. It is used with equal success in greenhouse growing they create an oxygen demand in receiving water bodies. and landscaping applications. Studies of perlite samples from

Sorption is a separation process responsible for the interfacial different places found that all perlite samples were amorphous with behavior of organic pollutants in water, soil and sediment systems, similar silica/alumina ratio (SiO :Al O ) but containing different 2 2 3which plays a critical role in the transport, fate, and ecotoxicological

amounts of accessory minerals. Furthermore, there are a number of activities, and even in the abatement and remediation measures of

studies on the use of perlite as an adsorbent for organic and the organic pollutants. Therefore, sorption properties and

inorganic compounds (Meesuk and Seammai, 2010).mechanisms have been extensively concerned by scientific

The results of Ghassabzadeha et al. (2010) showed that communities of environmental science (Chen et al., 2008). Sorption

expanded perlite exhibited high adsorption capacity for silver. onto natural solid materials, also called geosorption, is one of the

Koumanova and Peeva-Antova (2002) proved the efficiency of main processes affecting subsurface transport of organic

perlite for 4-chlorophenol removal from aqueous medium. contaminants through soil. Processes such as solute transport with * e-mail: z.yaneva@abv.bg

354

Satisfactory results were obtained during the single-component The expanded perlite used in the recent study as a sorbent for sorption of various dyes - Methyl Violet, Basic Blue 41 and o-NP adsorption was taken from deposits in the southern part of Methylene Blue on expanded, unexpanded and activated perlite Bulgaria. The material had not been subjected to any treatment, i.e. (Dogan et al., 2000; Dogan and Alkan, 2003; Roulia, 2005). Alkan it was applied in its natural form. It is mainly composed of silica as and Dogan (2001) investigated the effect of pH and temperature on SiO (70 - 80 %), aluminum as Al O (10 - 15 %), and K O, Na O (<10 2 2 3 2 2

the adsorption behavior of H SO activated perlite towards Cu (II). %). The specific surface area of expanded perlite, measured by 2 4

Other scientific teams proved the applicability of expanded perlite as BET-N adsorption (Sorptomatic 1900, Fisons Instruments), is 5.83 22an alternative adsorbent for Ag, Cu, Hg, Pb, Cd, Cr removal from m /g.

aqueous solutions (Yadanaparthi et al., 2001). The equilibrium experiments were accomplished using model The aim of the present work was to investigate the ability of the solutions of o-NP in distilled water. The investigations for the

ogeomaterial expanded perlite, in its unmodified form, to remove the mononitrophenol were carried out at temperature 19±2 C and pH 3recalcitrant toxic organic compound o-nitrophenol from simulated 6.1±0.2. Solutions were in the concentration range 5-30 mg/dm .

agricultural run-off water. The mechanism of the adsorption process Known amounts of perlite were added to the model solutions in was examined by comparative analyses of the applicability of the screw cap jars. The jars were shaken on a platform shaker. The Langmuir and Freundlich models. solute from each jar was then filtered. The residual o-NP

concentrations in the liquid phase (C ) were determined e

spectrophotometrically. The adsorption capacity of the geomaterial (q ) was calculated by the mass balance equation eq. (1):eMaterial and methods

(c - c ).V = (q - q ).W (1)o e e o3where c , mg/dm , is the initial mononitrophenol concentration o

in the liquid phase, q = 0 and w, g, is the adsorbent mass.o-Nitrophenol (o-NP) (Merck, 99 %), without further purification o

SPECORD UV-VIS, Carl Zeiss Jena, spectrophotometer was was used as an adsorbate in the recent investigations. This model used for o-NP concentration determinations at the corresponding substance is a typical representative of the hydrophobic ionic wavelength L 272 nm. Blanks containing no adsorbate and compounds (HIOCs) frequently found in natural surface bodies and max

wastewaters. The structural chemical formula and the replicates of each adsorption point were used for each experimental physicochemical characteristics of the mononitrophenol are series.presented in Figure 1 and Table 1, respectively.

ModelingThe Langmuir isotherm model is represented as (Langmuir,

1916):

(2)

where q , mg/g, is the equilibrium sorbate concentration in the e3solid phase; c , mg/dm , is the equilibrium sorbate concentration in e

3 3the liquid phase; a , dm /mg and K , dm /g, are the Langmuir L L

isotherm constants, which are evaluated through the linear form of eq. (2).

355

q =e

K cL e

1+a cL e

o -o

HO

+N

Figure 1. Structural chemical formula of o-NP.

Table 1. Physicochemical properties of o-NP.

Molecular mass,kg/kmol

Density,3g/cm

Solubility,g/100g H O2

Molecular volume3nm /mol

pKa Effective molecular diameter,nm

λ ,max

nm

* 0at 14 C

139.11 *1.495 0.2 0.191 7.23 0.813 272

The Freundlich model is expressed as (Freundlich, 1907): and science as the derived isotherms reveal the specific relation nF between the pollutant concentration and its uptake degree by the q = K . c , (3)e F e

3 solid phase at constant temperature. Thus, the adsorption isotherm where K , dm /g, and n - the heterogeneity factor, are the F F

of the studied mononitrophenol was obtained at optimum pH, Freundlich constants. Their values were determined from the linear adsorbent mass and contact time at various initial concentrations.form of the Freundlich equation.

The experimental equilibrium data of o-NP adsorption on perlite were described by the Langmuir and Freundlich models (Figure 2). The shape of the isotherm may also be considered to predict if an

Results and discussion adsorption system is “favorable” or “unfavorable”. The essential characteristic of a Langmuir isotherm can be expressed in terms of a

The knowledge of sorbate/sorbent adsorption behavior at dimensionless separation factor or an equilibrium parameter R, equilibrium conditions is essential for environmental engineering

356

which is defined by the following equation: R = 0: Irreversible adsorption.The calculated value of R for the system investigated was

(4) 0.568, i.e. the experimental isotherm of o-NP sorption on the geomaterial could, undoubtedly, be classified as favourable and

According to the value of R, the isotherm shape may be concave, characterizing with an initial steep section. The maximum interpreted as follows: attained adsorption capacity was q 1.68 mg/g. e

2 R > 1: Unfavourable adsorption; The calculated model parameters, regression coefficients (R ), R = 1: Linear adsorption; SSE and RMSE values for both mathematical models applied, were 0 < R < 1: Favourable adsorption; presented in Table 2. According to the mode of the experimental and

Figure 2. Experimental isotherm, Langmuir and Freundlich model of o-NP adsorption on expanded perlite.

q-1

’mg g

e

C -3e’mg dm

exp. data Langmuir model Freumdlich model

1.8

1.6

1.4

1.2

1

0.8

0.6

0.4

0.2

0

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

model equilibrium curves (Figure 2), obviously the Langmuir model bond between the H-atom of the -OH group and the O-atom from the displayed better correlation with the experimental data especially for -NO group, situated on ortho- place in the nitrophenol molecule 2

the low and middle concentration range, compared to the Freundlich could be accepted as an obstacle for possible chemical interaction model. The experimental points outlined a distinct steep vertical between the functional groups of the sorbate and those of the section in the low concentration region, where a sharp leap of sorbent. Moreover, Meesuk and Seammai (2010) stated that H-nitrophenol solid phase concentration from 0 to 0.7 mg/g was bonding between OH of the silanol or silanediol groups at the surface distinguished. Consequently, higher extent of adsorption during the of expanded perlite was also possible (Figure 3). Alternatively, there initial stages of the process could be expected. Considering that the could be H-bonding between OH of the silanol or silanediol groups of Freundlich model is based on multilayer adsorption on perlite and free water molecules (Meesuk and Seammai, 2010). heterogeneous surfaces with a non-uniform distribution of The assessment of the applicability of any low-cost material as adsorption heat, while the Langmuir isotherm model assumes an alternative adsorbent is inherently related to the evaluation of its monolayer coverage of adsorbent surfaces by the adsorbate at efficiency (E, %) expressed as:specific homogeneous sites within the adsorbent, it could be supposed that a greater number of o-NP molecules were sorbed on (5)the first sorbent layer; however the process proceeded to the inner layers of the solid particles, although at a lower rate and smaller The uptake efficiency of expanded perlite, calculated on the magnitude. The monolayer capacity displayed as K /a according to basis of the experimental results obtained in the recent study, at L L

the Langmuir model was 1.73 mg/g. various initial o-NP concentrations, constant model solutions Based on these observations and on the higher value of the volume and geomaterial mass are graphically displayed in Figure 4.

2 Obviously the highest attained extend of nitrophenol removal was 70 regression coefficient (R 0.9365) for the Langmuir model (Table 2), %, while the mean E, % for the concentration range 5 - 30 mg/dm3 it could be concluded that the latter gave better representation of the was 40 %.experimental data. Considering that o-NP effective molecular

Besides the assessment of the efficiency and adsorption diameter is 0.813 nm (Table 1) and the fact that expanded perlite capacity during the selection of an appropriate material as an belongs to the group of mesoporous sorbents (with pore radii in the alternative and effective sorbent for any specific sorption process, range 15 - 2000 Å), the hypothesis of possible pore blockage or other the cost of the adsorbent is also an important issue that has to be spatial obstacles during organic molecules sorption in the pores of considered from economical aspect. the natural material seem inconsistent.

However, the probable formation of intramolecular hydrogen

R = 1

1+K . CL e

E = .100 , %C - CO e

C O

357

Figure 3. Possible hydrogen bonds at the surface of perlite (Meesuk and Seammai, 2010)

OH OH OH OH OH OH

Si Si Si SiO O O

H-bonding in silanol groupH-bonding in silandiol group

Surface of perlite

Table 2. Values of the Langmuir, Freundlich, Redlich-Peterson, Temkin and multilayer isotherm model coefficients,

SSE and RMSE for the system 2-NP - expanded perlite

Model Coefficients 2R SSE RMSE

Langmuir

Freundlich

K 0.5133L

a 0.2964L

K 0.6067F

n 0.3029F

0.9365

0.9061

0.1345

0.0902

0.1640

0.1344

Conclusion References

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and theoretical results. The maximum adsorption capacity of the Chen BL, Zhou DD, Zhu LZ and Shen XY, 2008. Sorption

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carbonaceous biosorbents in aqueous solution. Science in China abundance of expanded perlite proved its applicability as an

Series B: Chemistry, 51, 5, 464-472.alternative sorbent for mononitrophenol removal. Besides, such

Daza A, Santamaroa C, Rodroagues-Navarro DN, Camacho M, separation method may facilitate the remediation of soils, natural

Orive R and Temprano F, 2000. Perlite as a carrier for bacterial and wastewaters subjected to nitrophenols contamination as a

inoculants. Soil Biology and Biochemistry, 32, 567-572.result of intensive and excessive pesticide and insecticide use in

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Figure 4. Efficiency of o-NP removal on expanded perlite from simulated agricultural run-off water.

E,%

3Co'mg/dm

70

60

50

40

30

20

10

0

5 15

20 25

30

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CONTENTS 1 / 2

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Reviews

1. Lameness scoring systems for cattle in dairy farmsT. Penev

Genetics and Breeding

2. Body and carcass parameters of sea bream (Sparus aurata L.) and sea bass (Dicentrarchus labrax L.)M. Marinova, I. Sirakov, Y. Staykov, E. Ivancheva

3. Effect of breed upon blood lysozyme and complement activity in different sheep breedsL. Sotirov, Ts. Koynarski, V. Semerdjiev, D. Dimov, S. Laleva, P. Slavova, M. Iliev, D. Yarkov

4. Winter wheat productivity under favorable and drought environments III. Effect of fertilizationA. Ivanova, N. Tsenov

5. Еvaluation of perspective sorghum breeding forms in their reaction to some diseases in field conditionsM. Georgieva – Andreeva, K. Tanova, S. Raykov

Nutrition and Physiology

Effect of dietary coconut oil supplementation oN some blood biochemical indices in yearling rams Т. Slavov, V. Radev, K. Sivkova, I. Varlyakov

Pharmacokinetics of tilmicosin after oral application of Pulmotil G 200 – premix in pigs D. Dimitrova, V. Кatsarov, D. Dimitrov, D. Tsoneva

Epidermal growth factor content in rabbit doe milk during the different lactation stages E. Vachkova, B. Bivolarski

Intraorbital glands in turkey broilers. III. Lacrimal gland histometryD. Dimitrov

Effect of body condition score at calving on body condition during lactation in Holstein and Brown Swiss cowsZh. Gergovska, T. Angelova, D. Yordanova, Zh. Krastanov, Ch. Miteva

Use of brewer's grains for feeding of lambsA. Kirilov, K. Ivanov

Production Systems

The effect of the milking liner design on the parameters of the milking machine pulsation system V. Vlashev, B. Banev, K. Peichev, G. Dineva

Accumulation dynamic of Ruta graveolens L. essential oil A. Dzhurmanski, G. Zhekova, D. Angelova

Research on the water regimen of soil upon the production of vine planting material N. Kovachev, N. Taneva, V. Kovachev, L. Halil

Agriculture and Environment

Influence of the farmiing, soil cultivation and Fertilization on the yield of wheatM. Nankov, L. Glogova

Study on the applicability of a natural geomaterial for mononitrophenol removal from simulated agricultural run-off water Z. Yaneva, B. Koumanova, N. Georgieva

CONTENTS 2 / 2

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 3, No 4, 2011

Comparative technical and economic analysis of variants for cleaning and storage of manure on a farm for 108 – 120 dairy cowsV. Dimova, D. Dinev, Y. Popova, Y. Mitev

Distribution of the black mussel Mytilus galloprovincialis (L.) along the Bulgarian Black Sea coast E. Petrova, St. Stoykov

Toxicity of plant protection products towards the imago of Encarsia Formosa Gah.V. Yankova, S. Masheva, B. Boev, K. Toskov

Effect of the rhizobacterium Bacillus subtilis on the development of the root-knot nematode Meloidogyne arenaria at different temperatures M. Mohamedova, H. Samaliev

Product Quality and Safety

Fatty acid composition of yogurt supplemented with walnut extract S. Boycheva, N. Naydenova, G. Mihaylova, T. Dimitrov, D. Pavlov

Near Infrared Spectroscopy for monitoring changes during yellow cheese ripeningS. Atanassova, N. Naydenova, T. Kolev, T. Iliev, G. Mihaylova

Short communications

Mechanical correction the traction weight of a farm wheeled tractorD. Irinchev

Possibilities for increasing the yield and quality of asters (Callistephus chinensis L.) cut flowerN. Miteva, O. Tafradziiski

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t hperformance in dairy cows, IX International Conference on Production Diseases in Farm Animals, Sept.11 – 14, Berlin, Germany, p. 302 (Abstr.).Thesis:Penkov D, 2008. Estimation of metabolic energy and true digestibility of amino acids of some feeds in experiments with muscus duck (Carina moshata, L). Thesis for DSc. Agrarian University, Plovdiv, 314 pp.

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