Dechlorination of chlorotoluene rectification residual liquid (CRRL) by using Williamson ether synthesis (WES) method.

Chlorotoluene rectification residual liquid (CRRL) from chlorotolune industry is hard to dispose of because of its high chlorine concentration, which poses high dioxin risk once it is subjected to incinerate. This research employed a chemical approach by using Williamson ether synthesis (WES) method for CRRL dechlorination. It shows that the sodium dosage, the ethanol dosage, and the ultrasonic time are the key factors in chlorine removal. The highest removal rate of chlorine was observed when the sodium dosage, the ethanol dosage, and the ultrasonic time were 0.35 g mL-1, 0.8 mL mL-1, and 15 min, respectively. The further optimization tests indicate that the highest chlorine removal efficiency of 39.06% was observed when the ultrasonic time was 15 min, the sodium dosage and the ethanol dosage were 0.5 g mL-1 and 1.1 mL mL-1, respectively. It suggests a feasible chlorine removal process for organic hazardous waste with high chlorine content before incineration.