ACTIVATION OF FLY ASH TO STABILISE LEAD CONTAMINATED SOILS AND SOLUTIONS

The role of pH on removal of metal contaminated solution was investigated by adding gradually drops of NaOH to lead solutions, the increase of the pH was observed and concentration of lead solution was measured by using ICP. The activated \ pulverised fly ash (PFA) was used as stabilizing material. The leaching behaviour of lead was investigated using 5 grams of the soil thoroughly mixed with 0.1g of the stabilising material in a polypropylene container to which 50ml of either deionised water; the mixture was shaken on a flat bed shaker for 2h, and then filtered using a What man No 542 filter paper. The lead concentration in the filtrate was determined by inductively coupled plasma-atomic emission spectrometry (ICP). The effect of adding PFA was a reduction in Pb released to an undetectable level at higher pH levels. Results from the analysis of X-ray diffraction on the soil samples retained on the filter paper showed the formation of lead sulphate and lead carbonate.