The removal of mercury (II) chloride (HgCl2), methylmercury (II) chloride (CH2HgCl), and phenylmercury(H) acetate (PhHgCH3QOO) from aqueous solutions by the char, prepared by carbonization of scrap tire at 500~800°C in a stream of nitrogen, was studied. The rate of removal of mercury compounds was so high as that of its adsorption on activated carbon (Fig. 2). Removal equilibrium data obeyed the Freundlich type isotherms over the concentration range 2~80mg-Hg/Z (Figs. 4~6). The char carbonized at 600°C showed higher removal capacity than that carbonized at other temperatures (Fig. 7). The effect of treatment with hydrochloric acid (10-3, 10-2, or 12N) on the char was also studied. For HgCl2 and CH3HgCl, the removal capacities of the char treated with 10-8 N hydrochloric acid were nearly equal to or less than that of untreated ones, while the removal capacity for PhHgCH3COO-increased by the same treatment (Figs. 9, 10). With increasing concentration of hydrochloric acid, the removal capacities of HgCl2 and CH3HgCl decreased appreciably, because zinc sulfide in the char was eluted by the acid treatment. The char contained approximately 10% ash, about 4% of which was zinc sulfide; zinc ion was eluted at the removal of HgCl2, and CH3.HgCL The atomic ratio of eluted zinc to removed mercury has been found to be about 0.6 for HgCl, and 0.4 for CH3HgCl, respectively (Fig. 13). In the case of PhHgCH3COO, however, elation of zinc ion was not observed. In conclusion, despite HgCl2 and CH3Hgcl were removed by the absorption and the chemical reactions (1) and (2), PhHgCH3COO was considered to be removed merely by the absorption. © 1979, The Chemical Society of Japan. All rights reserved.
