Chemical Kinetics of Stabilization

Since water-soluble contaminants will easily leach into the groundwater and enter the food chain, reduction of their leaching is the most important issue during waste stabilization. It is essential that the contaminants be first converted into their most insoluble form by 

Limits on Leaching (mg/1) as the Disposal Criteria in the TCLP Test. 

Hazardous Metal Oxidation State RCRA Limit UTS Limit 

To evaluate the leaching performance of the waste streams, we assume that soluble and sparsely soluble compounds will leach out and fail the TCLP and, hence, should be target contaminants for stabilization. These soluble or sparsely soluble components may directly be treated with phosphates and converted to their insoluble, nonleachable forms. The literature is full of studies on stabilization of such divalent hazardous metal contaminants (Pb, Cd, and Zn, in particular), where treatment with various phosphates has been elfective. These studies are summarized in Section 16.3. 

Solubility of Compounds Formed with Hazardous Metals. 

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