References
[1]. Aksu, Z., Ozer, D., Ekiz, H.I., Kutsal, T., & Calar, A. (1996). Investigation of Biosorption of Chromium (VI) on Cladophora Crispata in Two-Staged Batch Reactor, Environ. Technol., 17, 215-220.
[2]. Alam, M.Z, Muyibi, S.A, & Toramae, J. (2007). Statistical optimization of adsorption processes for removal of 2,4-dichlorophenol by activated carbon derived from oil palm empty fruit bunches, J.Environ.Sci. 19, 674-677.
[3]. Chakravathi, A.K., Chowadary, S.B., Chakrabarty, S., Chakrabarty, T., & Mukherjee, D.C. (1995). Liquid membrane multiple emulsion process of chromium (VI) separation from waste waters, Colloids, Surf.A, 103, 59-71.
[4]. Das, A.K. (2004). Micellar effect on the kinetics and mechanism of chromium (VI) oxidation of organic substrates, Coord, Chem.Rev. 248, 81.
[5]. Gomez, V., Callo, M.P. (2006). Chromium determination and speciation since 2000, Trends. Anal. Chem., 25, 1006-1015.
[6]. Gupta, S., & Babu, B.V. (2009). Utilization of waste product (Tamarind seeds) for the removal of Cr (VI) from aqueous solutions: Equilibrium, kinetics and regeneration studies, J.Environ.Man. 90, 3013-3022.
[7]. Hasan, S.H., Singh, K.K., Prakash, O., Talat, M., & Ho, Y.S. (2008). Removal of Cr (VI) from aqueous solutions using agricultural waste maize bran, J.Hazard.Mater. 152, 356-365.
[8]. Huang, S.D., Fann, C.F., & Hsiech, H.S. (1982). Foam separation of chromium (VI) from aqueous solution, J.Colloid.Interface.Sci., 89, 504-513.
[9]. Jain, M., Garg, V.K., & Kadirvelu, K. (2011). Investigation of Cr(VI) adsorption on to chemically treated Helianthus annus:Optimization using response surface methodology, Bioresour.Technol., 102, 600-605.
[10]. Kiran, B., Kaushik, A., & Kaushik, C.P. (2007). Response surface methodology approach for optimizing removal of Cr(VI) from aqueous solution using immobilized Cynobacterium, Chem. Eng. J., 126, 147-153.
[11]. Kowalshi, Z. (1994). Treatment of chromic tannery wastes, J.Hazard Mater., 39, 137-144.
[12]. Kongsricharoern, N., & Polprasert, C. (1996). Chromium removal by a bipolar electro-chemical precipitation process, Water.Sci.Technol. 34, 109-116.
[13]. Krishna, D., & Padma Sree, R. (2012). Removal of Chromium (VI) from aqueous solution by Limonia Acidissima hull powder as adsorbent, i-manager's Journal on Future Engineering & Technology, Vol. 7, No. ,27-38.
[14]. Krishna, D., & Padma Sree, R. (2012). Removal of Chromium (VI) from aqueous solution by Ragi husk powder as adsorbent, i-manager's Journal on Future Engineering & Technology, Vol. 8, No. 6-18.
[15]. Li, H., Li, Z., Liu, T., Xiao, X., Peng, Z., & Deng, L. (2008). A novel technology for biosorption and recovery hexavalent chromium in wastewater by bio-functional magnetic beads, Bioresour. Technol., 99, 6271-6279.
[16]. Madaria, P.R., Mohan, N., Rajagopal, C., & Garg, B.S. (2004). Application of carbon aerogel for electrolytic removal of mercury from aqueous solutions, Journal of Scientific & Industrial Research, 63, 938-943.
[17]. Montgomerry, D.C. (2001). Design and Analysis of Experiments, 5th ed., John Wiley Sons, New York, USA.
[18]. Muthukumar, M., Mohan, D., & Rajendran, M. (2003). optimization of mix proportions of mineral aggregates using Box-Behnken design of experiments, Chem.Concr.Res. 25,751-758.
[19]. Pagilla, K.R., & Canter, L.W. (1999). Laboratory studies on remediation of Chromium –contaminated soils, J.Environ.Eng, 125, 243-248.
[20]. Park, D., Yun, Y.S., & Park, J.M. (2010). The past, present and, and future trends of biosorption, Biotechnol.Bioprocess.Eng, 15, 86-102.
[21]. Seaman, J.C., Bertsch, P.M., & Schwallie, L. (1999). In-Situ Cr (VI) reduction within coarse – textured oxide-coated soil and aquifer systems using Fe (II) solutions, Environ.Sci.Technol. 33, 938-944.
[22]. Shafey, E.I. (2005). Behavior of reduction-sorption of chromium (VI) from an aqueous solution on a modified sorbent from rice husk, Water Air Soil Pollution. 163, 81-102.
[23]. Sikaily, A.E.,. Nemr, A.E., Khaled, A., & Abdelwahab, O. (2007). Removal of toxic chromium from waste water using green alga Ulva lactuca and its activated carbon, J.Hazard.Mater., 148, 216-228.
[24]. Tarangini, K., Kumar, A., Satapathy, G.R., & Sangal, V.K. (2009). Statistical optimization of process parameters for Cr (VI) biosorption onto mixed cultures of Pseudomonas aeruginosa and Bacillus subtillis, Clean, 37, 319-327.
[25]. Tiravanti, G., Petruzzelli, D., & Passino, R. (1997). Pretreatment of tannery wastewaters by an ion-exchange process for Cr (III) removal and recovery, Water.Sci.Technol. 36, 197-207.
[26]. Toles, C.A., Marshell, W.E., & Johns, M.M. (1997). GAC from nutshells for the uptake of metal ions and organic compounds, Carbon, 35, 1414-1470.
[27]. Veglio, F., & Beolchini, F. (1997). Removal of metals by biosorption: a review, Hydrometallurgy. 44, 301-316.
[28]. Volesky, B., & Holan, Z.R. (1995). Biosorption of heavy metals, Biotechnology. Prog. 11, 235-250.
[29]. World Health Organization, Guidelines for drinking water quality, 3rd ed., Genrva Vol.1. 2004, p 334.
[30]. Zhou, X., Korenaga, T., Takahashi, T Moriwake, T & Shinoda, S. (1993). A process monitoring/controlling system for the treatment of waste water containing (VI), Water Res. 27, 1049.