EDTA对Al-Ni合金脱氯降解水体中2-氯酚的影响

Effect of EDTA addition on dechlorination of 2-chlorophenol with Al-Ni alloy particles

利用商业Al-Ni合金颗粒,在EDTA的络合作用下,对水体中的2-氯酚进行脱氯降解,实验考察了溶液pH、EDTA四钠浓度的影响以及该合金颗粒重复脱氯效果.结果表明,EDTA的存在能显著促进Al-Ni合金颗粒对水体中2-氯酚的脱氯降解效率,溶液pH的增加可有效提高2-氯酚的降解速率;Al-Ni合金投加量在10 g·L-1,pH值为11.0,EDTA四钠浓度10 mmol·L-1时,反应45 min,0.389 mmol·L-1的2-氯酚去除率超过99%,产物主要是苯酚;合金颗粒重复实验8次的2-氯酚脱氯率仍在95.9%以上,表明上述工艺具有长时间的催化活性.

In this study, the commercially available Al-Ni alloy was used to dechlorinate 2-chlorophenol （2-CP） with the addition of EDTA. The effects of aqueous pH and the concentration of EDTA on dechlorination performance were investigated; and then the long-term dechlorination efficiency using the alloy particles was evaluated. As a result, the presence of EDTA significantly increased the deehlorination efficiency of 2-CP using Al-Ni alloy. In addition, the dechlorination rate of 2-CP also increased with increasing solution pH. More than 99% 2-CP （0.389 mmol. L^-1） was dechlorinated into phenol within 45 minutes at pH 11.0 with 10mmol. L^-1 of EDTA- 4Na using 10g.L^-1 of Al-Ni alloy. With the addition of EDTA, Al-Ni alloy maintained high catalytic activity for long-term dechlorination, which was able to remove 95.9% of 2-CP after 8 cycles.