Studies on chromium (III) removal from aqueous solution by adsorption ontobiogas residual slurry and its application to tannery wastewater treatment

Adsorption studies of Cr(III) on biogas residual slurry (BRS) were caried o ut under varying conditions of shaking time (5-180 min), metal ion concentr ation (10-40 mg L-1), adsorbent concentration (1.0 to 8.0 g L-1) and initia l pH (1.5- 5.0). Adsorption follows Langmuir isotherm, being endothermic in nature. For a Cr(III) concentration of 10 mg L-1, a maximum removal of 85% by 4 g L-1 of adsorbent was obtained at an initial pH greater than or equa l to 3.0. Desorption of Cr(III) from the spent adsorbent has also been inve stigated. Removal of Cr(III) from tannery wastewater by BRS was testified.