Color and Cod Removal From Treated Textile Industry Effluents with Various Adsorbents

Abstract

The rapid depletion and pollution of water resources are extremely negative impact on all life in Ergene River Basin in Turkey. The highly polluted sites were Corlu and Cerkezkoy in the basin which located near the most urbanized and industrialized area. New discharge standards were developed by Turkish Water Pollution Control Regulation (TWPCR) for COD (chemical oxygen dimend) and color to prevent pollution caused by insufficient wastewater treatment in the basin. The aim of this study was to evaluate the color and COD removal efficiency of various adsorbents for biologically treated effluents of a local textile factory in Corlu which has COD: 200 mg/L and color: 39.4 m(-1). In the study four adsorbents were used: the waste metal hydroxide (WMH) obtained from aluminum electroplating industry, colemanite waste (CW) and ulexite waste (UW) collected from boron ore wastes and magnetic nanoparticles (Fe3O4) (MNP). The adsorption of color and COD onto different adsorbents were studied at natural pH (pH 7.5), different adsorbent doses (2-30 g/L) and different contact times (0, 15, 30, 60, 90, 120, 150, 180 min). The color removal efficiencies of WMH and UW were bigger than MNP and CW. Adsorption with UW achieved to equilibrium at 120 min and with WMH at 180 min. The maximum color removal efficiencies were 67% for UW and 57% for WMH. The maximum COD removal efficiencies were 72% for UW and 70% for WMH. Both adsorbents were reduced COD below 100 mg/L and color below 20 m(-1). Freundlich model yielded better fit than the Langmuir model for the adsorption of color and COD on UW and WMH.