Adsorption characteristics of mango (<i>magnifera indica</i>) seed shell activated carbon for removing phenol from wastewater

Abstract

Adsorption characteristics of mango (Magnifera indica) seed shell activated carbon for phenol rem-oval from wastewater were examined by experimental single stage batch operation. Contact time, stirring rate, adsorbent dose, pH, initial phenol concentration, carbon particle size and impregnation ratio of ZnCl₂ to the seed shells were the variables controlling the adsorption rates. The optimum carbon dose was 10 g/L of water for both Chur-kpev (local) and Dausha (improved) varieties at stirring rate of 98 rpm and pH range of 4 - 8. Phenol removal increased with initial phenol concentration for activated Dausha 1:2, Chur-kpev 1:2 and Chur-kpev 1:3, and initial phenol concentration of 0.123 mg/L was chosen as the optimum level. The phenol adsorbed increased with contact time, and 120 minutes was the optimum time for phenol adsorption. The amount of phenol adsorb-ed was inversely proportional to the carbon particle size, and the optimum particle size range of 150 - 300 μm was adopted for phenol removal. The percentage of phenol adsorbed and adsorptive capacity of the activated carbons decreased with the levels of ZnCl₂ impregnation. The mass ratio of 1 part of ZnCl₂ to 2 parts of mango seed shells (1:2) for the two mango varieties was the best impregnation ratio. The activated chur-kpev variety exhibited best adsorption characteristics for phenol removal from the wastewater