SELECTIVE ADSORPTION OF AQUEOUS Hg~(2+), Pb~(2+), Cd~(2+), As~(3+) AND Au~+ ONTO ACTIVATED CARBON DERIVED FROM HIGH SULPHUR COAL

摘要

The adsorption of aqueous Hg~(2+), Pb~(2+), Cd~(2+), As~(3+), and Au+ onto sulphur-impregnated activated carbon (SIAC) was investigated. SIAC samples used in this study included one commercial SIAC and one SIAC sample derived from high sulphur coal using KOH and SO_2 sequential activation process. Their specific surface area (SSA) ranged from 561 to 608 m~2/g, and sulphur contents were 8 to 10%. The adsorption of Hg~(2+), Pb~(2+), Cd~(2+), As~(3+), and Au~+ from single ion solutions and adsorptive selectivity from a mixture solution were investigated, as well as the effects of initial concentration and adsorption temperature on adsorption capacity for individual cations. Competing with other ions, gold displayed the strongest affinity to the SIACs.