Sains Malaysiana 46(4)(2017): 655–665

http://dx.doi.org/10.17576/jsm-2017-4604-19

Synthesis of Silica-supported Nanoiron for Cr(VI) Removal: Application of Box-Behnken Statistical Design (BBD)

(Sintesis Besi Nano Disokong Silika untuk Penyingkiran Cr(VI): Aplikasi Reka Bentuk Statistik Box-Behnken (BBD))

PRAEWPATRA ARCHARIYAPANYAKUL¹, BHUCKCHANYA PANGKUMHANG²,

PUMMARIN KHAMDAHSAG^3,4,5 & VISANU TANBOONCHUY^2,5,6*

¹Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani 12120, Thailand

²Department of Environmental Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002 Thailand

³Environmental Research Institute, Center of Excellence on Hazardous Substance Management

Chulalongkorn University, Bangkok 10330, Thailand

⁴Research Unit of Site Remediation on Metals Management from Industry and Mining, Center of Excellence on Hazardous Substance Management, Chulalongkorn University, Bangkok 10330

Thailand

⁵Research Program of Toxic Substance Management in Mining Industry, Center of Excellence on Hazardous Substance Management, Chulalongkorn University, Bangkok 10330, Thailand

⁶Research Center for Environmental and Hazardous Substance Management (EHSM)

Khon Kaen University, Khon Kaen 40002, Thailand

Diserahkan: 25 April 2016/Diterima: 7 September 2016

ABSTRACT

This study aimed to optimize the condition of silica-supported nanoscale zero valent iron (NZVI/SiO₂) synthesis by colloidal impregnation method. Box-Behnken design (BBD) was used as a tool to create and analyze the 17 synthesized conditions of NZVI/SiO₂ samples. The independent variables included ethanol concentration (0-100 vol%), amount of silica (0.025-0.125 g) and agitation speed (100-400 rpm). In addition, analysis of variance (ANOVA) for a response surface quadratic model was used to approximate statistical relationship of independent variables. The reducing performance of the synthesized NZVI/SiO₂ was examined through removal of Cr(VI) contaminated in water. The optimum of NZVI/SiO₂ synthesis was validated with 100 vol% of ethanol concentration, 0.075 g of silica amount, and 100 rpm of agitation speed. The materials were characterized using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and nitrogen adsorption/desorption which showed the existence of NZVI phase, composition, and morphology. The Cr(VI) removal efficiency of the NZVI/SiO₂ was tested further at the solution pH 4, 7 and 10 in comparison with that by pristine NZVI and silica-unsupported NZVI (NZVI + SiO₂). Among the three materials, NZVI/SiO₂ presented the highest Cr(VI) removal, especially at pH 7 and 10 with 98 and 94.41%, within 60 min. This was due to the adsorption of Cr(OH)₃ and Fe(OH)₃ precipitates over SiO₂ resulting in availibilty of NZVI/SiO₂’s active sites. The proposed mechanism of Cr(VI) removal by NZVI/SiO₂ was also described.

Keywords: Box-Behnken design; chromium; NZVI; silica-supported nanoiron

ABSTRAK

Kajian ini bertujuan untuk mengoptimumkan keadaan sintesis besi skala nano disokong silika bervalensi sifar (NZVI/SiO₂) melalui kaedah pemadatan koloid. Reka bentuk Box-Behnken (BBD) telah digunakan sebagai alat untuk mencipta dan menganalisis sampel 17 keadaan sintesis NZVI/SiO₂. Pemboleh ubah bebas termasuk kepekatan etanol (0-100 vol%), silika (0.025-0.125 g) dan kelajuan goncangan (100-400 rpm). Selain itu, analisis varians (ANOVA) untuk model quadratik tindak balas permukaan telah digunakan untuk menganggar hubungan statistik pemboleh ubah bebas. Pengurangan prestasi sintesis NZVI/SiO₂ telah disemak melalui penyingkiran Cr(VI) tercemar dalam air. Sintesis NZVI/SiO₂ optimum telah disahkan dengan 100 vol% kepekatan etanol, 0.075 g silika dan 100 rpm kelajuan goncangan. Bahan ini telah dicirikan menggunakan pembelauan sinar-x (XRD), mikroskop elektron imbasan dengan spektroskopi tenaga serakan sinar-x (SEM-EDX) dan nitrogen penjerapan/penyahjerapan yang menunjukkan kewujudan fasa NZVI, komposisi dan morfologi. Kecekapan penyingkiran Cr(VI) NZVI/SiO₂ telah diuji selanjutnya pada larutan pH 4, 7 dan 10 berbanding dengan NZVI asli dan NZVI tidak disokong silika (NZVI/SiO₂). Antara ketiga-tiga bahan, NZVI/SiO₂ menunjukkan penyingkiran Cr(VI) tertinggi, terutamanya pada pH 7 dan 10 dengan 98 dan 94.41% dalam masa 60 minit. Ini disebabkan penjerapan Cr(OH)₃ dan mendakan Fe(OH)3 ke atas SiO₂ yang mengakibatkan ketersediaan tapak aktif NZVI/SiO₂. Mekanisme cadangan penyingkiran Cr(VI) oleh NZVI/SiO₂ turut dibincangkan.

Kata kunci: Besi nano disokong silika; kromium; NZVI; reka bentuk Box-Behnken

RUJUKAN

Anderson, R.A. 1997. Chromium as an essential nutrient for humans. Regulatory Toxicology Pharmacology 26: 35-41.

Astrup, T., Stipp, S.L.S. & Christensen, T.H. 2000. Immobilization of chromate from coal fly ash leachate using an attenuating barrier containing zero-valent iron. Environmental Science & Technology 34: 4163-4168.

Blowes, D.W., Ptacek, C.J. & Jambor, J.L. 1997. In situ remediation of Cr(VI) contaminated ground water using permeable reactive walls: Laboratory studies. Environmental Science & Technology 31: 3348-3357.

Chang, L.Y. 2005. Chromate reduction in wastewater at different pH levels using thin iron wires-a laboratory study. Environmental Progress 24: 305-316.

Chang, L.Y. 2003. Alternative chromium reduction and heavymetal precipitation methods for industrial wastewater. Environmental Progress 22: 174-182.

Chen, S.S., Cheng, C.Y., Li, C.W., Chai, P.H. & Chang, Y.M. 2006. Reduction of chromate from electroplating wastewater from pH 1 to 2 using fluidized zero valent iron process. Journal of Hazardous Materials 142: 362-367.

Coller-Myburgh, C.V., Rensburg, L.V. & Maboeta, M. 2014. Utilizing earthworm and microbial assays to assess the ecotoxicity of chromium mine wastes. Applied Soil Ecology 83: 258-265.

Costa, M. 2003. Potential hazards of hexavalent chromate in our drinking water. Toxicology and Applied Pharmacology 188: 1-5.

Dassi, D., Frikha, F., Zouari, M.H., Belbahri, L., Woodward, S. & Mechichi, T. 2012. Application of response surface methodology to optimize decolourization of dyes by the laccase-mediator system. Journal of Environmental Management 108: 84-91.

Fu, R., Yang, Y., Xu, Z., Zhang, X., Guo, X. & Bi, D. 2015. The removal of chromium (VI) and lead (II) from groundwater using sepiolite-supported nanoscale zero-valent iron (S-NZVI). Chemosphere 138: 726-734.

Guha, S. & Bhargava, P. 2005. Removal of chromium from synthetic plating waste by zero-valent iron and sulfate-reducing bacteria. Water Environment Research 77: 411-416.

Katz, S.A. & Salem, H. 1993. The toxicology of chromium with respect to its chemical speciation: A review. Journal of Applied Toxicology 13: 217-224.

Kiattisaksiri, P., Khamdahsag, P., Khemthong, P., Pimpha, N. & Grisdanurak, N. 2014. Photocatalytic degradation of 2,4-dichlorophenol over Fe-ZnO catalyst under visible light. Korean Journal of Chemical Engineering. DOI: 10.1007/ s11814-014-0379-6.

Kohn, T., Livi, K.J.T., Roberts, A.L. & Vikesland, P.J. 2005. Longevity of granular iron in groundwater treatment processes: Corrosion product development. Environmental Science & Technology 39: 2867-2879.

Li, X., Ai, L. & Jiang, J. 2016. Nanoscale zerovalent iron decorated on graphene nanosheets for Cr(VI) removal from aqueous solution: Surface corrosion retard induced the enhanced performance. Chemical Engineering Journal 288: 789-797.

Li, X.Q., Cao, J. & Zhang, W.X. 2008. Immobilization of hexavalent chromium with Iron nanoparticles: Characterizations with high resolution X-ray photoelectron spectroscopy (HR-XPS). Industrial & Engineering Chemistry Research 47: 2131-2139.

Liu, C., Fiol, N., Poch, J. & Villaescusa, L. 2016. A new technology for the treatment of chromium electroplating wastewater based on biosorption. Journal of Water Process Engineering 11: 143-151.

Mocellin, J., Mercier, G., Morel, J.L., Blais, J.F. & Simonnot, M.O. 2015. Factors influencing the Zn and Mn extraction from pyrometallurgical sludge in the steel manufacturing industry. Journal of Environmental Management 158: 48-54.

Oh, Y.J., Song, H., Shin, W.S., Choi, S.J. & Kim, Y.H. 2007. Effect of amorphous silica and silica sand on removal of chromium(VI) by zero-valent iron. Chemosphere 66: 858- 865.

Padmavathy, K.S., Madhu, G. & Haseena, P.V. 2016. A study on effects of pH, adsorption dosage, time, initial concentration and adsorption isotherm study for removal of hexavalent chromium (Cr(VI)) from wastewater by magnetite nanoparticles. Procedia Technology 24: 585-594.

Powell, R.M. & Puls, R.W. 1997. Proton generation by dissolution of intrinsic or augmented aluminosilicate minerals for in situ contaminant remediation by zero-valence-state iron. Environmental Science & Technology 31: 2244-2251.

Powell, R.M., Puls, R.W., Hightower, S.K. & Sabatini, D.A. 1995. Coupled iron corrosion and chromate reduction: Mechanisms for subsurface remediation. Environmental Science & Technology 29: 1913-1922.

Sass, B.M. & Rai, D. 1987. Solubility of amorphous chromium(III)-iron(III) hydroxide solid-solution. Inorganic Chemistry 26: 2228-2232.

Shih, Y.J., Chen, C.W., Hsia, K.F. & Dong, C.D. 2015. Granulation for extended-release of nanoscale zero-valent iron exemplified by hexavalent chromium reduction in aqueous solution. Separation and Purification Technology 156: 1073-1081.

Tanboonchuy, V., Grisdanurak, N. & Liao, C.H. 2012. Nitrate probe for quantifying reducing power of nanoscale zero-valent iron. Sustainable Environment Research 22: 185-191.

Tanboonchuy, V., Hsu, J.C., Grisdanurak, N. & Liao, C.H. 2011. Gas-bubbled nano zero-valent iron process for high concentration arsenate removal. Journal of Hazardous Materials 186: 2123-2128.

Tantriratan, P., Wirojanagud, W., Neramittagapong, S., Wantala, K. & Grisdanurak, N. 2011. Optimization for UV-photocatalytic degradation of paraquat over titanium dioxide supported on rice husk silica using Box-Behnken design. Indian Journal of Chemical Technology 18: 363-371.

Toli, A., Chalastara, K., Mystrioti, C., Xenidis, A. & Papassiopi, N. 2016. Incorporation of zero valent iron nanoparticles in the matrix of cationic resin beads for the remediation of Cr(VI) contaminated waters. Environmental Pollution 214: 419-429.

Tripathi, P., Srivastava, V.C. & Kumar, A. 2009. Optimization of an azo dye batch adsorption parameters using Box-Behnken design. Desalination 249: 1273-1279.

Vikesland, P.J., Klausen, J., Zimmermann, H., Roberts, A.L. & Ball, W.P. 2003. Longevity of granular iron in groundwater treatment processes: Changes in solute transport properties over time. Journal of Contaminant Hydrology 64: 3-33.

Wang, Q., Snyder, S., Kim, J. & Choi, H. 2009. Aqueous ethanol modified nanoscale zerovalent iron in bromate reduction: Synthesis, characterization and reactivity. Environmental Science & Technology 43: 3292-3299.

World Health Organization (WHO). 2004. Guidelines for Drinking-water Quality. 3rd ed. Recommendations. WHO, Geneva. 1: 334-335.

Wu, C., Li, C., Leng, D. & Cui, D. 2016. Factors affecting the reductive properties of the core-shell Sio2-coated iron nanoparticles. Advances in Chemical Engineering and Science 6: 316-323.

Wu, L., Liao, L., Lv, G. & Qin, F. 2015. Stability and pH-independence of nano-zero-valent iron intercalated montmorillonite and its application on Ce(VI) removal. Journal of Contaminant Hydrology 179: 1-9.

Yirsaw, B.D., Megharaj, M., Chen, Z. & Naidu, R. 2016. Reduction of hexavalent chromium by green synthesized nano zero valent iron and process optimization using response surface methodology. Environmental Technology & Innovation 5: 136-147.

Zhang, Y., Li, Y., Li, J., Hu, L. & Zheng, X. 2011. Enhanced removal of nitrate by a novel composite: Nanoscale zero valent iron supported on pillared clay. Chemical Engineering Journal 171: 526-531.

Zhou, X., Lv, B., Zhou, Z., Li, W. & Jing, G. 2015. Evaluation of highly active nanoscale zero-valent iron coupled with ultrasound for chromium(Vi) removal. Chemical Engineering Journal 281: 155-163.

*Pengarang untuk surat-menyurat; email: visanu@kku.ac.th