Optimization of ultrasonic extraction of polycyclic aromatic hydrocarbons from sewage sludge samples

The influence of different conditions of ultrasonic extraction on the recovery ofpolycyclic aromatic hydrocarbons (PAHs) from sewage sludge samples was studied. Various extraction times (2 × 30, 2 × 60, 2 × 90 min), and various solvents (toluene, cyclohexane, dichloromethane, acetone, methanol, tetrahydrofuran, n-hexane) were applied. Solid phase extraction on octadecyl C 1 8 sorbent was performed to purify sample extracts. HPLC and UV detection were employed to separate and quantify the studied PAHs. The method described was used in practice to measure the PAHs' content in the sludge samples from the municipal treatment plants. The PAHs' concentration was found to be 37 mg kg - 1 . The dominating hydrocarbons were: benzo[b]fluoranthene (17.8%), fluoranthene (15.9%), pyrene (13.7%), and benzo[k]fluoranthene (11.9%).