Removing heavy metals from aq. soln. by adsorption on silica gel with specific surface and pore vol.

摘要

Heavy metals are removed from aq. solns. by adsorption on SiO2 gel with specific surface 200-1000 square m/g and pore vol. 0.2-1.8 ml/g.The SiO2 gel has specific surface 400-800 square m/g, pore vol. 0.4-1.5 ml/g, and particle size up to 500 (50-300) microns. Adsorption is (dis)continuous, in a column or on a screen. Adsorption is followed by regeneration with an aq. agent, pref. an acid, esp. 0.1-2 (0.1-1) mols.l of a mineral acid, and is (dis)continuous, in a column or on a screen. The heavy metal is isolated from the regenerant.