Research Article Heat-Resistant Ceramic Pigments …downloads.hindawi.com/archive/2013/369174.pdfC. Q quartz: P and potassium vanadium sulfate. T : Chemical composition of the waste

Hindawi Publishing CorporationJournal of Waste ManagementVolume 2013 Article ID 369174 6 pageshttpdxdoiorg1011552013369174

Research ArticleHeat-Resistant Ceramic Pigments on the Base ofWaste Vanadium Catalyst and Alumina

M B Sedelnikova N V Liseenko Y I Pautova and V M Pogrebenkov

Department of Silicate Technology and Nanomaterials Tomsk Polytechnic University 30 Lenin Avenue Tomsk 634050 Russia

Correspondence should be addressed to M B Sedelnikova smasha5yandexru

Received 17 December 2012 Revised 13 March 2013 Accepted 17 March 2013

Academic Editor Brajesh Dubey

Copyright copy 2013 M B Sedelnikova et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

Ceramic pigments on the base of technogenic silica-containing materialmdashwaste vanadium catalyst were obtained in this workCorundum is identified along with the predominant mullite phase in the composition of pigments The ions of nickel chromiumand iron are embedded in the structure if the concentration of the corresponding oxide in the initial mixture does not exceed10wt In this case the oxide is not identified in a free form according to the results of X-ray diffraction analysis Spinel CoAl

2O4

is formed in cobalt pigments The developed pigments keep the firing temperature up to 1200∘C The obtained pigments may berecommended for ceramic paints and colored glazes for building materials

1 Introduction

At the present the construction industry needs decorativebuilding materials which are produced with the applyingof ceramic pigments dyes and decorative glaze There hasbeen a great interest within the ceramic industry in thedevelopment of high-stability pigments which show intensetonality and satisfy both technological and environmentalrequirements [1] While the first step in pigment productioninvolves the judicious choice of raw materials current trendsare towards alternative and less expensive raw materials[2ndash4] Normally the materials of a high chemical purityare used for pigment production Selected industrial wasteshave been investigated for this purpose and in particularmetal-rich sludges [5ndash8] Indeed industrial processes suchas galvanizing or surface coating consume large amounts ofwater yielding high volumes of sludge which requires bothenvironmental and economic treatments [7] Black ceramicpigments were prepared from CrNi-rich sludge generatedfrom CrNi plating and Fe-rich galvanizing sludge generatedduring steel wiredrawing [9] In another work chroma-tinred malayaite Ca(Cr Sn)SiO

5pigment was synthesized

using CrNi plating sludge [10] The ceramic pigments withwollastonite and diopside structures were produced usingnepheline sludge [11]

The requirements to raw materials for ceramic pigmentproduction are constant chemical composition purity (nocoloring impurities) and the ability to form stable crystallinestructure Ceramic pigments with the structure of the potas-sium feldspar were obtained in [12] with the use of a wastevanadium catalyst The drawback of these pigments is lowsynthesis temperature 800ndash950∘C and limited applicationin overglaze ceramic dyes and for coloring of easily fusibleglazes Ceramic pigments with the mullite structure arecharacterized by high fire resistance and can be used for bothoverglaze and underglaze dyes

The crystal structure of mullite (3Al2O3sdot 2SiO

2) is similar

to the sillimanite one despite some differences in theircompositions A characteristic feature of themullite structureis the presence of two types of the Al3+ ions a half of thementer into the crystal lattice with the coordination number6 the other half with the coordination number 4 [13] Thepigments with the mullite structure are widespread and wellknown They are synthesized from pure chemical agents at1200ndash1300∘C [14]

The purpose of this work was the production andinvestigation of heat-resistant ceramic pigments with mul-lite structure by using industrial waste vanadium cata-lyst

2 Journal of Waste Management

5 15 25 35 45 55

Rela

tive i

nten

sity

2120579 (∘)

Q

Q

Q

Q Q

QQ

QQ Q

Q

Q

QQQ

Q Q Q Q QQ Q

QQQ

Q

Q

QQ Q

QQ

QQ

QQ

Vanadium catalyst initialP P P P P PP

PP P P P

Vanadium catalyst 950∘C



Figure 1 The XRD data of vanadium catalysts initial and calcinated at the temperatures 800 900 and 950∘C Q quartz P and potassiumvanadium sulfate

Table 1 Chemical composition of the waste vanadium catalyst

Raw material Oxide content wtΔ119898

1

SiO2 Al2O3 V2O5 K2OWaste vanadium catalyst 6490 520 620 910 14601Ignition loss wt

2 Materials and Methods

21 Raw Materials and Formulations The raw material usedin the study was a waste vanadium catalyst (WVC) whichis used for the manufacture of sulfuric acid in the plantldquoNitrogenrdquo (Kemerovo Russia) in the work

Raw materials for WVC are natural diatomite vanadiumoxide (V

2O5) potassium oxide (K

2O) and sulfur oxide (SO

3)

in the form of potassium vanadium sulfate (K2S2O7sdotV2O5)

Diatomite contains 90 of the shells of diatomite seaweed2ndash7 of quartz the rest are feldspar glauconite and mica

The chemical composition of WVC was determined byX-ray fluorescence analysis (XRF Philips X1015840UNIQUE II)(Table 1) Initial WVC contains significant amount of highlyvolatile components in the form of sulfur oxide SO

3 Thus

previously WVC was treated by heating at the temperatures900ndash950∘C for one hour to apply it for ceramic pigmentproduction Calcination at this temperature is necessary toremove the volatile impurities of sulfur oxide at the sametime vanadium oxide is removed too The main product ofcalcination is SiO

2according the XRD data (Figure 1) The

other oxides (Al2O3 K2O) are contained in small quantities

(see Table 1) so their reflexes are weak on radiographs Themajor part of V

2O3was captured and removed along with

volatile compounds during the heat treatmentThe final colorof pigments and dyes was not affected by V

2O3 which has its

own coloring abilityThe WVC comprised the structure-forming oxidesmdash

SiO2 and Al

2O3 Aluminum oxide (Al

2O3) was added to the

catalyst to provide mullite structure formation Al2O3was

999 of purity and particle size of 20ndash30 120583m

22 Preparation and Characterisation of Pigments Wastevanadium catalyst was milled up to particle size less than20ndash30 microns Aluminum oxide is included in the catalystcomposition but in a small concentration (up to 5wt)which is not enough to form mullite So additional aluminawas added to WVC to obtain stoichiometric mullite by thefollowing reaction

(SiO2Al2O3K2O) + Al

2O3

997888rarr 3Al2O3sdot 2SiO

2(solid solution)

+ glass phase (SiO2Al2O3K2O)

(1)

Firstly WVC of 42wt and alumina of 58wt weremixed without any chromophore by dry method in a ballmill for 3 h This mixture was named as ldquocheck samplerdquo (CS)and used to determine structure formation The preparedcomposition mixture was sintered in corundum pots at119879sint = 1100ndash1200∘C The XRD analysis showed that mullite-corundum structure was formed instead of expected mulliteone This indicates that Al

2O3has not completely reacted

and remained in the reaction products But this fact does notaffect the properties of the obtained pigments in particularon heat resistance The mixtures on the base of WVCAl

2O3

in proportions considering the content additive were madeto obtain pigments (Table 2) Water-soluble salts (nitrate orsulfate) of the d-elements Ni2+ Co2+ Fe3+ and Cr3+ wereinjected in the mixture as chromophores When heated thedecomposition of salts up to oxides and the removal ofvolatile residues take place The chromophores have a highdiffusion capacity in this state and as a result provide a stablebright color of pigmentsThe preparedmixture was subjectedto wet grinding in a ball mill for 1 h dried at 119879 = 120∘C for2 h and sintered in corundum pots at 119879sint = 1100ndash1200

∘CPrepared materials were being grinded in a ball mill for 24 hThe obtained samples were ground to a residue on the sieveno 0063 (the size of the cell is 63120583m or 10000 holesm2)no more than 02 wt to provide a uniform coating duringfurther pigments application

Journal of Waste Management 3

Table 2 The initial compositions to obtain mullite pigments

Sample number The content of main components wtWVC Al2O3 CoO NiO Cr2O3 Fe2O3

CS2 42 58 mdash mdash mdash mdashM1 38 57 5 mdash mdash mdashM3 34 51 15 mdash mdash mdashM4 38 57 mdash 5 mdash mdashM6 34 51 mdash 15 mdash mdashM7 38 57 mdash mdash 5 mdashM8 36 54 mdash mdash 10 mdashM9 38 54 mdash mdash mdash 5M10 36 57 mdash mdash mdash 102CS check sample (without chromophores)

10 20 30 40 50 60

M

M

MM

MM

M

M

M M

M

L

L

L

L L C C CC

CC

CC

C

C

CC

SS

Checksample

2120579 (∘)

Rela

tive i

nten

sity

PigmentM2

PigmentM8

Figure 2 Radiograms of the check sample and the pigments ofmullite composition (119879sint = 1200

∘C) M mullite (3Al2O3sdot 2SiO

2)

C corundum (Al2O3) L leucite (K(AlSi

2O6)) S spinel (CoAl

2O4)

A preliminary characterisation of pigments involved theidentification by X-ray diffraction (XRD-7000S Shimadzu) ofthe main crystalline phases formed upon firing and mea-surements of the CIE Lab colour parameters The reflectancedata in the visible region were used to obtain the threerelevant parameters 119871lowast 119886lowast and 119887lowast measuring the light-ness redgreen and yellowblue hue intensities respectively[15] The spectral reflection curves were measured on thespectrophotometer Cary 100 Scan to determine the colorcharacteristics using MgO as a reference The microstructureof the powders was revealed by scanning electronmicroscope(Philips SEM 515)

3 Result and Discussion

Polyphase structure was obtained at the firing of the sampleswithout chromophores at the 119879 = 1100∘C It consistedof mullite (119889 = 0 540 0 348 0 255 nm) corundum (119889 =0 282 0 208 0 173 nm) and leucite in a small quantity(119889 = 0326 02827 nm) (Figure 2) SEM data confirmed theformation of mullite and corundum (Figure 3) The needlecrystals were characteristic for mullite and the plate ones forcorundum

Table 3 The color of the pigments and some overgraze dyes

Sample number The color of overglaze dyes1100∘C3 1200∘C3 850∘C3

M1 (Co2+) Sky blue Greenish blue Sky blueM3 (Co2+) Blue Blue BlueM4 (Ni2+) Light green Light olive Light greenM6 (Ni2+) Turquoise Turquoise (darker) TurquoiseM8 (Cr3+) Dark olive Dark olive Brownish pinkM9 (Fe3+) Light brown Reddish brown BrownM10 (Fe3+) Brown Reddish brown Brown3Sintering temperature (119879sint)

∘C

Some amorphization of the pigment structure wasobserved with the increase in the firing temperature upto 1200∘C It was associated with the presence of fusiblepotassium oxide K

2O in the WVC (91 wt) (see Table 1)

The intensity of the all reflections decreased when thechromophore was added (see Figure 2) This was due to thesymmetry breaking and the crystal lattice distortion whenthe ionic chromophores incorporated into the structure andsolid solutions formed [16] It was assumed that the processof isomorphous entry of ionic-chromophores in mullitestructure occurred in the position of aluminum Al3+(1199033+Al =0053 nm) Based on the similarity of the ionic radii andthe equality of the charges the process was more activewith the participation of Cr3+ (1199033+Cr = 0063 nm) and Fe3+

(1199033+Fe = 0064 nm) ions than at the presence of the Co2+

(1199032+Co = 0072 nm) and Ni2+ (1199032+Ni = 0069 nm) ones Nickelchromium and iron ions were embedded in the structure upto the concentration of the corresponding oxide 10wt at119879sint = 1200

∘C The oxides were not identified in a free formaccording to the result of XRD analysis (see Figure 2) It isknown that the maximum solubility of Fe

2O3in mullite at

119879sint = 1600∘C is 12 wt Cr

2O3mdash10wt [13]

The spinel CoAl2O4(119889 = 0242 0200 nm) formed in

the cobalt pigments As a result the pigments were coloredin bright blue tones due to the tetrahedral coordination ofthe ion Co2+ in the spinel structure The tone of the cobalt-containing pigments might be changed from sky blue to


Table 4 Color characteristics of the obtained ceramic pigments and dyes (119879sint = 1200∘C)

Sample number Pigment colour parameters Dye colour parameters119871

lowast119886

lowast119887

lowast119871

lowast119886

lowast119887

lowast

M1 (Co2+) 480 00 minus160 580 00 minus150M3 (Co2+) 380 00 minus190 440 00 minus100M4 (Ni2+) 530 minus60 61 660 minus10 110M6 (Ni2+) 460 minus60 47 560 minus40 94M8 (Cr3+) 440 24 28 540 100 190M9 (Fe3+) 470 43 99 570 110 150M10 (Fe3+) 380 76 71 540 52 180

(a) (b)

Figure 3 SEM images of the pigments of mullite composition (a) check sample (b) chromium-containing pigmentThe areas on the imagesare 1mdashmullite and 2mdashcorundum (119879sint = 1200∘C)

blue depending on the concentration of oxide CoO (Table 3Figure 4) Nickel oxide NiO gave pigments turquoise coloriron oxide Fe

2O3mdashreddish brown one The coloration of the

chromium-containing pigments varied from brownish pink(5wt Cr

2O3) to dark olive (10 wt Cr

2O3) It depends

on the polarization value and the distance between thechromium ion and its surrounding ions The greater thedistance between the Cr3+andO2minus the weaker the connectionand the less polarization of chromium ion The absorptionmaximumwas shifted to the red spectrum thus the pigmentswere painted in green tones

The pigments of mullite composition were tested asoverglaze colors (see Table 3)They were mixed with the fluxThe chemical composition of concentrated fluxwas as follows(wt) SiO

2(168) B

2O3(158) PbO6 (74) The contents

of the pigment and flux were in the ratio 1 3 Such dyeswere deposited on glazed ceramic articles and fired at atemperature of 850∘C Blue turquoise red and brown paintswere gotten The color of the pigments did not change inoverglaze dyes Besides the obtained pigments were added tothe compositions of porcelain glazes in the amount of 5 wtThe glazes were calcinated at the temperature 1200∘C As aresult bright colored coverings were obtainedThe color of allpigments in a glaze did not change too which indicated thestability of the pigments under high temperatures in contrastto the pigments presented in [12]

The color coordinates 119871lowast 119886lowast and 119887lowast (Table 4) whichcharacterize the color properties of the pigments werecalculated using the spectral reflectance curves (Figure 5)For example cobalt pigments had a higher color saturationwhich was confirmed by high values of blowast in the blue spectralregion of the system CIE 119871lowast 119886lowast and 119887lowast [15]

4 Conclusion

The ceramic pigments were produced using technogenicsilica-containing raw materialmdashwaste vanadium catalyst inthe work Corundum phase along with the predominantmullite is identified in the composition of the obtainedpigments and dyes The ions of nickel chromium and ironare embedded in the structure up to the concentration of thecorresponding oxide 10wt in this case the oxide is notidentified in a free form on XRD patternThe spinel CoAl

2O4

forms in the cobalt-containing pigments Cobalt pigments arecharacterized by the highest color saturation The developedpigments keep a firing temperature up to 1200∘C

The research results show that the usage of vanadiumcatalyst is promising and economically expedient because thepigments synthesized on its basis are not inferior industrialpigments by color properties and heat resistance and theyexceed the pigments described in [9ndash12] The pigmentsobtained in this work can be recommended for underglaze


M1 M4

M2 M6

M8

M10

M9

(a)

M1 M4M2 M6 M8 M10M9

(b)

M1 M4M2 M6 M8 M10M9

(c)

Figure 4The color of the obtained pigments (a) overglaze dyes (b)and glazes (c)

0102030405060708090

400 450 500 550 600 650 700 750 800

Refle

ctan

ce (

)

Wavelength (nm)

M3 CoO

M7 Cr2O3

M8 Cr2O3

M10 Fe2O3

M6 NiO

Figure 5 Spectral reflectance curves of the obtained pigments (119879sint= 1200∘C)

and overglaze ceramic dyes colored glazes and for coloringof building materials

Abbreviations

XRF X-ray fluorescenceXRD X-ray diffractionSEM Scanning electron microscopyWVC Waste vanadium catalyst119879sint Sintering temperature ∘CCIE Lab Commission Internationale

IrsquoEclairagemdashinternational commission onillumination of the standard colorimetriccoordinates119871lowast 119886lowast and 119887lowast

Acknowledgments

The work was supported by the Ministry of Education andScience of Russian Federation The state task is ldquoSciencerdquo no330552011

References

[1] Y Marinova J M Hohemberger E Cordoncillo P Escribanoand J B Carda ldquoStudy of solid solutions with perovskitestructure for application in the field of the ceramic pigmentsrdquoJournal of the European Ceramic Society vol 23 no 2 pp 213ndash220 2003

[2] F Andreola L Barbieri and F Bondioli ldquoAgricultural waste inthe synthesis of coral ceramic pigmentrdquoDyes and Pigments vol94 no 2 pp 207ndash211 2012

[3] R I Lazau C Pacurariu D Becherescu and R Ianos ldquoCeramicpigments with chromium content from leather wastesrdquo Journalof the European Ceramic Society vol 27 no 2-3 pp 1899ndash19032007

[4] E Ozel S Turan S Coruh and N O Ergun ldquoProduction ofbrown and black pigments by using flotation waste from copperslagrdquo Waste Management and Research vol 24 no 2 pp 125ndash133 2006

[5] F Bondioli L Barbieri and T Manfredini ldquoGrey ceramicpigment (Fe Zn)Cr

2O4obtained from industrial fly-ashrdquo Tile

amp Brick International vol 16 no 4 pp 246ndash248 2000[6] V Gomes A P N de Oliveira and J A Labrincha ldquoCeramic

pigment based on mullite structure obtained from Al-sludgecontaining formulationsrdquo The American Ceramic Society Bul-letin vol 84 pp 9501ndash9504 2005

[7] M J Ribeiro D U Tulyaganov J A Labrincha and J MF Ferreira ldquoProduction of Al-rich sludge-containing ceramicbodies by different shaping techniquesrdquo Journal of MaterialsProcessing Technology vol 148 no 1 pp 139ndash146 2004

[8] G Costa M J Ribeiro T Trindade and J A LabrinchaldquoDevelopment of waste-based ceramic pigmentsrdquo Boletin de laSociedad Espanola de Ceramica y Vidrio vol 46 no 1 pp 7ndash132007

[9] G Costa V P Della M J Ribeiro A P N Oliveira G Monrosand J A Labrincha ldquoSynthesis of black ceramic pigments fromsecondary raw materialsrdquo Dyes and Pigments vol 77 no 1 pp137ndash144 2008

[10] G Costa M J Ribeiro J A Labrincha M Dondi F Matteucciand G Cruciani ldquoMalayaite ceramic pigments prepared withgalvanic sludgerdquo Dyes and Pigments vol 78 no 2 pp 157ndash1642008

[11] M B Sedelrsquonikova and V M Pogrebenkov ldquoProduction ofceramic pigments with wollastonite and diopside structuresusing nepheline sludgerdquo Glass and Ceramics vol 64 no 9-10pp 363ndash365 2007

[12] M B Sedelrsquonikova V M Pogrebenkov V V Gorbatenko andE Y Kautsman ldquoCeramic pigments for construction ceramicsrdquoGlass and Ceramics vol 66 no 9-10 pp 305ndash309 2009

[13] M K Murthy and F A Hummel ldquoX-ray study of the solidsolution of TiO Fe

2O3 and G O

3in mullite (3Al

2O3a2SiO

2)rdquo

Journal of the American Ceramic Society vol 43 no 5 pp 267ndash273 1960

[14] S Kurajica E Tkalcec and J Schmauch ldquoCoAl2O4mdashmullite

composites prepared by sol-gel processesrdquo Journal of the Euro-pean Ceramic Society vol 27 no 2-3 pp 951ndash958 2007


[15] R Tilley Ed Colour and the Optical Properties of MaterialsJohn Wiley amp Sons London UK 2000

[16] Encyclopedia of Spectroscopy and Spectrometry 2nd edition1999

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ClimatologyJournal of


5 15 25 35 45 55

Rela

tive i

nten

sity

2120579 (∘)

Q

Q

Q

Q Q

QQ

QQ Q

Q

Q

QQQ

Q Q Q Q QQ Q

QQQ

Q

Q

QQ Q

QQ

QQ

QQ

Vanadium catalyst initialP P P P P PP

PP P P P




Figure 1 The XRD data of vanadium catalysts initial and calcinated at the temperatures 800 900 and 950∘C Q quartz P and potassiumvanadium sulfate

Table 1 Chemical composition of the waste vanadium catalyst

Raw material Oxide content wtΔ119898

1

SiO2 Al2O3 V2O5 K2OWaste vanadium catalyst 6490 520 620 910 14601Ignition loss wt

2 Materials and Methods

21 Raw Materials and Formulations The raw material usedin the study was a waste vanadium catalyst (WVC) whichis used for the manufacture of sulfuric acid in the plantldquoNitrogenrdquo (Kemerovo Russia) in the work

Raw materials for WVC are natural diatomite vanadiumoxide (V

2O5) potassium oxide (K

2O) and sulfur oxide (SO

3)

in the form of potassium vanadium sulfate (K2S2O7sdotV2O5)

Diatomite contains 90 of the shells of diatomite seaweed2ndash7 of quartz the rest are feldspar glauconite and mica

The chemical composition of WVC was determined byX-ray fluorescence analysis (XRF Philips X1015840UNIQUE II)(Table 1) Initial WVC contains significant amount of highlyvolatile components in the form of sulfur oxide SO

3 Thus

previously WVC was treated by heating at the temperatures900ndash950∘C for one hour to apply it for ceramic pigmentproduction Calcination at this temperature is necessary toremove the volatile impurities of sulfur oxide at the sametime vanadium oxide is removed too The main product ofcalcination is SiO

2according the XRD data (Figure 1) The

other oxides (Al2O3 K2O) are contained in small quantities

(see Table 1) so their reflexes are weak on radiographs Themajor part of V

2O3was captured and removed along with

volatile compounds during the heat treatmentThe final colorof pigments and dyes was not affected by V

2O3 which has its

own coloring abilityThe WVC comprised the structure-forming oxidesmdash

SiO2 and Al

2O3 Aluminum oxide (Al

2O3) was added to the

catalyst to provide mullite structure formation Al2O3was

999 of purity and particle size of 20ndash30 120583m

22 Preparation and Characterisation of Pigments Wastevanadium catalyst was milled up to particle size less than20ndash30 microns Aluminum oxide is included in the catalystcomposition but in a small concentration (up to 5wt)which is not enough to form mullite So additional aluminawas added to WVC to obtain stoichiometric mullite by thefollowing reaction

(SiO2Al2O3K2O) + Al

2O3

997888rarr 3Al2O3sdot 2SiO

2(solid solution)

+ glass phase (SiO2Al2O3K2O)

(1)

Firstly WVC of 42wt and alumina of 58wt weremixed without any chromophore by dry method in a ballmill for 3 h This mixture was named as ldquocheck samplerdquo (CS)and used to determine structure formation The preparedcomposition mixture was sintered in corundum pots at119879sint = 1100ndash1200∘C The XRD analysis showed that mullite-corundum structure was formed instead of expected mulliteone This indicates that Al

2O3has not completely reacted

and remained in the reaction products But this fact does notaffect the properties of the obtained pigments in particularon heat resistance The mixtures on the base of WVCAl

2O3

in proportions considering the content additive were madeto obtain pigments (Table 2) Water-soluble salts (nitrate orsulfate) of the d-elements Ni2+ Co2+ Fe3+ and Cr3+ wereinjected in the mixture as chromophores When heated thedecomposition of salts up to oxides and the removal ofvolatile residues take place The chromophores have a highdiffusion capacity in this state and as a result provide a stablebright color of pigmentsThe preparedmixture was subjectedto wet grinding in a ball mill for 1 h dried at 119879 = 120∘C for2 h and sintered in corundum pots at 119879sint = 1100ndash1200

∘CPrepared materials were being grinded in a ball mill for 24 hThe obtained samples were ground to a residue on the sieveno 0063 (the size of the cell is 63120583m or 10000 holesm2)no more than 02 wt to provide a uniform coating duringfurther pigments application





10 20 30 40 50 60

M

M

MM

MM

M

M

M M

M

L

L

L

L L C C CC

CC

CC

C

C

CC

SS

Checksample

2120579 (∘)

Rela

tive i

nten

sity

PigmentM2

PigmentM8



2)



2O4)







∘C







2O3in mullite at

119879sint = 1600∘C is 12 wt Cr

2O3mdash10wt [13]






lowast119886

lowast119887

lowast119871

lowast119886

lowast119887

lowast


(a) (b)






2O3) It depends



2(168) B




4 Conclusion


2O4




M1 M4

M2 M6

M8

M10

M9

(a)

M1 M4M2 M6 M8 M10M9

(b)

M1 M4M2 M6 M8 M10M9

(c)


0102030405060708090

400 450 500 550 600 650 700 750 800

Refle

ctan

ce (

)

Wavelength (nm)

M3 CoO

M7 Cr2O3

M8 Cr2O3

M10 Fe2O3

M6 NiO



Abbreviations



Acknowledgments


References
















2O3 and G O

3in mullite (3Al

2O3a2SiO

2)rdquo











Journal of












Volume 2014

Advances in









Geophysics


















10 20 30 40 50 60

M

M

MM

MM

M

M

M M

M

L

L

L

L L C C CC

CC

CC

C

C

CC

SS

Checksample

2120579 (∘)

Rela

tive i

nten

sity

PigmentM2

PigmentM8



2)



2O4)







∘C







2O3in mullite at

119879sint = 1600∘C is 12 wt Cr

2O3mdash10wt [13]






lowast119886

lowast119887

lowast119871

lowast119886

lowast119887

lowast


(a) (b)






2O3) It depends



2(168) B




4 Conclusion


2O4




M1 M4

M2 M6

M8

M10

M9

(a)

M1 M4M2 M6 M8 M10M9

(b)

M1 M4M2 M6 M8 M10M9

(c)


0102030405060708090

400 450 500 550 600 650 700 750 800

Refle

ctan

ce (

)

Wavelength (nm)

M3 CoO

M7 Cr2O3

M8 Cr2O3

M10 Fe2O3

M6 NiO



Abbreviations



Acknowledgments


References
















2O3 and G O

3in mullite (3Al

2O3a2SiO

2)rdquo











Journal of












Volume 2014

Advances in









Geophysics

















lowast119886

lowast119887

lowast119871

lowast119886

lowast119887

lowast


(a) (b)






2O3) It depends



2(168) B




4 Conclusion


2O4




M1 M4

M2 M6

M8

M10

M9

(a)

M1 M4M2 M6 M8 M10M9

(b)

M1 M4M2 M6 M8 M10M9

(c)


0102030405060708090

400 450 500 550 600 650 700 750 800

Refle

ctan

ce (

)

Wavelength (nm)

M3 CoO

M7 Cr2O3

M8 Cr2O3

M10 Fe2O3

M6 NiO



Abbreviations



Acknowledgments


References
















2O3 and G O

3in mullite (3Al

2O3a2SiO

2)rdquo











Journal of












Volume 2014

Advances in









Geophysics















M1 M4

M2 M6

M8

M10

M9

(a)

M1 M4M2 M6 M8 M10M9

(b)

M1 M4M2 M6 M8 M10M9

(c)


0102030405060708090

400 450 500 550 600 650 700 750 800

Refle

ctan

ce (

)

Wavelength (nm)

M3 CoO

M7 Cr2O3

M8 Cr2O3

M10 Fe2O3

M6 NiO



Abbreviations



Acknowledgments


References
















2O3 and G O

3in mullite (3Al

2O3a2SiO

2)rdquo











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Documents

Research Article Heat-Resistant Ceramic Pigments …downloads.hindawi.com/archive/2013/369174.pdfC. Q quartz: P and potassium vanadium sulfate. T : Chemical composition of the waste