Adsorption and bound characteristics of soil minerals with Hg

Adsorption thermodynamics and kinetics experiments indicate that the sequence of adsorption capacity as well as the adsorption strength of five types of soil minerals tO Hg is MnO₂>Fe₂O₃> bentonite>kaolinite>CaCO₃．The differences of speciation distribution characteristics of mineral bound Hg can reflect the stability and corresponding quantity of mineral bound Hg under different environmental conditions．Volatilization experiment verifies that the environmental aCtivity of mineral bound Hg is strongly influenced by its speciation distribution as well as the adsorption capacity and strength of minerals with Hg．The higher the proportions of water soluble and exchangeable Hg and acid soluble Hg are，the higher the environmental activity of the mineral bound Hg will be．The higher the proportions of alkali soluble and residual Hg are，the lower the environmental activity of the mineral bound Hg will be．