Effect of Mineral Systems Injected with Zinc Sulfide on Arsenite Removal from Aqueous Solution: Part II

摘要

Mineral systems of kaolinite, montmorillonite, goethite and their mixtures were investigated to determine their effect on arsenite removal. Experimental studies include characterization and batch mode experiments. This study was in relation to solution composition and ageing relevant to streams and groundwater impacted by arsenic. Sorption isotherms indicated that sorption capacities of the different clay minerals, goethite and their mixtures were dependent on particle size, pH, particle concentration, arsenic concentration and residence time. Batch mode studies at room temperature revealed increase in sorption as pH was increased. All mineral systems exhibited increase in sorption as initial arsenic concentration increased. All mineral systems exhibited both promotive and non-promotive Cp effects. The complex behavior of mineral systems over the range of residence time investigated may be attributed to increased hydroxylation of the mineral surface and availability of thiol (≡S-H) and hydroxyl (≡Me-OH) functional groups and reactive sites.