The leachability propensity of El-Lajjun Jordanian oil shale ash

This work reports the leachability of heavy matals and major anions from Jordanian spent oil shale after combusion. Oil shale samples were combusted at temperatures of 550 Degree, 650 degree and 850 degree characterization of the produced solid ash was perfoemed based on XRD analyses. Leaching tests on the ash samples were conduced for different periods of time. Experimental results indicate that level of heavy matals such as Cd, Pb, Zn, Cu, Cr in the leachate is below the maximum level set by the Environmental Protection Authority (EPA). For instance, the maxium level of Cd measured in the leachate solution was 0.14 ppm, which is below the EPA limit. Results also indicate that even that even though the level of heavy metals in all samples was below the EPA limits, yet the level of heavy metals increases as the temperature of the ashing process increases. The effect of ashing temperature on ash cation exchange capacity (CEC) and the pH of ash solution were studied and found to increase with increasing ashing temperature. (authors).