Ni-Fe双金属对氯代苯酚催化还原脱氯的试验

分别采用Ni-Fe双金属体系和单一零价铁对氯代有机物2,4-二氯苯酚、2-氯苯酚和4-氯苯酚进行了催化还原脱氯的研究。结果表明:单一零价铁能够对氯代苯酚还原脱氯,但效率不高,通常在10%～25%。在镍的催化作用下,零价铁对氯代苯酚的还原脱氯效率大大提高。当零价铁加入量为60 g/L,硫酸镍为0.6 g/L,初始氯代苯酚的质量浓度在25 mg/L左右,反应初始pH值控制在偏酸性的条件下,还原脱氯效率可达到70%以上。氯代苯酚降解的准一级速率常数和降解率满足以下规律:4-氯苯酚大于2-氯苯酚大于2,4-二氯苯酚。

A test of catalytic reductive dechlorination of chlorophenol by Ni-Fe bimetal

Ni-Fe bimetal and zero-valent iron were respectively used in the catalytic reductive dechlorination treatment of chlorinated organic compounds 2,4-dichlorophenol,2-chlorophenol and 4-chlorophenol.The results showed that: the zero-valent iron could be used to reductively dechlorinate chlorophenols with efficiency about 10%-25%.Under the catalytic effect of falcial,the efficiency of zero-valent iron on reductive dechlorination of chloro-phenols was greatly improved.When the dosage of zero-valent iron,nickel sulfate were 60 g/L,0.6 g/L respectively,the initial concentration of the dechlorination was about 25 mg/L,the initial pH was acidity,the reductive dechlori-nation rate could above 70%.The pseudo first order rate constants and the degradation rate of the chlorophenols confirmed the descending order as following: 4-CP,2-CP and 2,4-DCP.