Behavior of three- to four-ring PAHs in the presence of oil shale ash and aluminosilicate matter

Abstract

Ash generated by oil shale combustion contains polycyclic aromatic hydrocarbons (PAHs) hazardous for environment and human health. The leaching of three- to four-ring PAHs sorbed on oil shale ash and zeolite NaA used as reference matter was investigated. The uptake of PAHs on ash was linearly correlated with the molecular surface area and Kow. The ash and zeolite have similar specific surface area and different characteristics of pores contribution to the total pore volume. The sorption capacity of ash for PAH was four times less than that of aluminosilicate. PAHs sorbed on ash particles leached more readily than those on zeolite. After 3 hr the amount of leached PAHs was 89.6% for phenanthrene and 30% for less-soluble anthracene. In field conditions during the disposing time, the mineral composition and sorptive capacity of ash may change and affect the mobility of PAHs.