Stabilization of Lead through pH Adjustment

It is possible to add chemicals, for example calcium carbonate, to the blasting medium prior to blasting or to the debris afterward, so that the pH of the test solution in the TCLP is altered. At the right pH, circa 9 in the figure above, lead is not soluble in the test solntion and thus is not measured. The debris passes the test for lead. However, this is not an acceptable technique because the lead itself is not permanently 

Source Hock, V. et al., Demonstration of lead-based paint removal and chemical stabilization using blastox, Technical Report 96/20, U.S. Army Construction Engineering Research Laboratory, Champaign, IL, 1996. 

Stabilized. The effect, nonsoluble lead, is extremely temporary after a short time, it leaches precisely as if no treatment had been done [13]. 

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