Removal of Mercury from Wastewater by Adsorption Using Thiol-Functionalized Eggshell Membrane

The thiol-functionalized eggshell membrane (TF-ESM) was prepared by esterification between thioglycolic acid (CH2SHCOOH) and oxygen-containing functional groups on eggshell membrane (ESM). A promising potential biosorbent, TF-ESM, was used for the removal of toxic mercury in wastewater. Aqueous of mercury ions removing properties by TF-ESM were studied through batch experiments. The results indicated that the modified ESM has greatly enhanced the adsorption capacity for Hg2+, the maximum capacity was increased more than 3-fold in comparison with the unmodified ESM, from 19.4 mg g-1 to 71.9 mg g-1. The optimum of pH value for Hg adsorption was in the range of 2-8, which the removing rate over 96%. The results obtained show that the novel thiol-functionalized eggshell membrane performed well the removal and recovery of mercury from low concentration wastewaters.