Study on preparation of activated carbon from corncob furfural residue with ZnCI_2 by microwave irradiation

摘要

In this paper, the feasibility of preparing activated carbon from corncob furfural residue with ZnCl_2 by microwave irradiation was studied. The effect of the ratio by weight of ZnCl_2 to corncob furfural residue, ZnCh solution soaking time, microwave irradiation time and the pH value of ZnCl_2 solution on the quality of activated carbon was investigated. On the condition that the microwave power is 800 W and ZnCl_2 solution mass concentration is 50%, the best technological parameter on preparing activated carbon with ZnCl_2 by microwave irradiation is obtained: at the ratio of 3.5:1 by weight of ZnCl_2 to corncob furfural residue, microwave irradiation time is 20 min, ZnCl_2 solution soaking time is 12 h, the pH value of ZnCl_2 solution is 2, the activated carbon yield reached 33.1% and the decolorizing capacity for methylene blue is 202.5 mg/g, the product is used in treating Cr~(6+) solution(pH value 4.0, concentration 50 mg/L), its adsorption capacity of Cr6+ is 7.583 mg/g.