Effects of key reaction parameters on the reductive dechlorination of chloroform with Pd/Fe~0 bimetal in aqueous solution

摘要

In this study, bimetallic Pd/Fe~0 particles were synthesized and employed to reduce chloroform in aqueous solution. The investigation emphasized on the effects of some key reaction parameters including Pd/Fe~0 dosage, pH, oxidation-reduction potential (ORP) and presence of anions on the reductive dechlorination reaction. The experimental results showed that high Pd/Fe~0 dosage, low initial pH and low ORP benefited the reductive dechlorination of chloroform. The ORP values in the aqueous chloroform solution bubbled with different gases of N_2, O_2 and air varied significantly and the efficiency of chloroform degradation under different atmospheres followed an order from high to low as N_2 > air > O_2. The experiments also demonstrated that SO_4~(2-) and NO_3~- ions inhibited the dechlorination reaction significantly, while H_2PO_4~- ion had no significant influence on the dechlorination.