title: Treatment of textile industry effluents using orange waste: a proposal to reduce color and chemical oxygen demand.
abstract: Various agricultural residues have been tested as biosorbents due to their low cost, high surface area, and favorable surface chemistry. In this work, a sweet orange albedo was tested as a biosorbent for treatment of real textile effluents. The orange albedo powder was prepared by drying the residue at 50 °C and milling to 30 mesh, and then used for dye adsorption from a alkaline (pH = 10.71) effluent. The adsorption process was studied in batch experiments at 30 °C by measuring color removal and chemical oxygen demand (COD). The color removal was found not to be significantly altered when the effluent was used in its raw state, while COD increased probably due to albedo degradation. For the effluent diluted to 60% (Veffluent VH2O(-1)), color and COD removal percentages of approximately 89% were obtained. It was found that pH played a very significant role on the adsorption process, as the treated albedo displayed a relative pHPZC* of 4.61, and the highest dye removal efficiencies were reached at pH lower than 2. The COD was strongly influenced by the effluent dilution. The effectiveness in eliminating color and COD shows that orange albedo can be potentially used as a biosorbent to treat textile wastewater.
authors.affiliation: Center of Technology, Federal University of Alagoas, Campus A. C. Simões, Maceió, AL 57072-970, Brazil E-mail: eduardo.farias.ufal@gmail.com.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: de Farias Silva
authors.affiliation: Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, AL, Brazil.
authors.forename: Andreza Heloiza
authors.initials: AH
authors.lastname: da Silva Gonçalves
authors.affiliation: Department of Food Technology, Federal University of Sergipe, São Cristóvão, SE, Brazil.
authors.forename: Ana Karla
authors.initials: AK
authors.lastname: de Souza Abud
mesh_terms: D000327:Adsorption; D057919:Biological Oxygen Demand Analysis; D032084:Citrus sinensis / Q000737:chemistry*; D003116:Color; D007220:Industrial Waste / Q000032:analysis*; D013783:Textile Industry; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D007220:Industrial Waste; D062065:Wastewater