In situ remediation of soils polluted with heavy metals. Part I. Using of supported materials

In this paper are presented principal aspects concerning remediation of soils polluted with metals by using of supported material, for their immobilization. Soil treatment for in situ immobilization of metals like Pb, Cd, Zn, etc. is realized using different materials: bio solids, synthetic or native zeolites, zeolites and clays supported with poly-nuclear aluminum salts, ashes. Synthetic and natural zeolites are used both for remediation of soils polluted with heavy metals and for soil quality improvement, retaining of water, ammonia and pH control. The most used supported materials are natural zeolites which decrease metals mobility and increase their retaining on imobile solid phases. Aluminum (Al13) basic poly-chloride and montmorillonite supported with poly-nuclear salts, are used as immobilizing agents for treatment of soils polluted with metals, e.g. 1-8 mmol Al13/kg d.s. were used for zinc immobilization, and 0.1-6% native volcanic tuff – (Al)n is applied to soil in order to decrease cadmium and lead mobility.