用尖晶石CoFe_(2)O_(4)磁性颗粒非均相芬顿氧化废水中的柠檬酸镍

Heterogeneous Fenton oxidation of nickel citrate in wastewater by using magnetic spinel CoFe_(2)O_(4) particles

采用溶胶-凝胶法制备了Fe_(3)O_(4)、CoFe_(2)O_(4)、CuFe_(2)O_(4)、NiFe_(2)O_(4)、MnFe_(2)O_(4)等5种尖晶石磁性颗粒,并研究了其作为催化剂非均相Fenton氧化柠檬酸镍的效果。结果表明CoFe_(2)O_(4)的催化活性明显高于其他4种磁性颗粒,且具有较好的循环稳定性。以CoFe_(2)O_(4)为催化剂,研究了非均相Fenton反应的最佳条件。对于含0.5 mmol/L柠檬酸镍的废水,在初始pH为3、催化剂投加量为0.3 g/L、30 mmol/L H_(2)O_(2)分3批次平均投加的情况下,柠檬酸镍的去除率可达97%,进一步加碱沉淀可去除废水中99%以上的镍。

Five kinds of spinel magnetic particles i.e.Fe_(3)O_(4),CoFe_(2)O_(4),CuFe_(2)O_(4),NiFe_(2)O_(4),and MnFe_(2)O_(4) were prepared by sol-gel method,and their use as a catalyst for heterogeneous Fenton oxidation of nickel citrate was studied.The results showed that the catalytic activity of CoFe_(2)O_(4) was much higher than the other 4 kinds of magnetic particles,and CoFe_(2)O_(4) also had good reusability.The optimal conditions of heterogeneous Fenton oxidation for nickel citrate with a concentration of 0.5 mmol/L when using CoFe_(2)O_(4) as catalyst were studied.The removal efficiency of nickel citrate reached up to 97% by dosing 10 mmol/L of H_(2)O_(2) for 3 times in the presence of 0.3 g/L of catalyst at an initial pH of 3,and more than 99%of nickel was removed by further precipitation with alkali.