沉淀法制备镍催化剂及其提高次氯酸钠氧化性能的研究

Improving oxidation performance of NaClO with Ni-based catalyst prepared by immerse precipitation method

以氧化铝/氧化镁为载体,采用浸没沉淀法制备了负载型镍基催化剂,并利用BET、环境扫描电镜和热重-差热分析等对其进行了表征,并对制备的催化剂进行了催化次氯酸钠分解产生有效氯的性能评价。结果表明:镍基催化剂的孔主要集中在中孔,这有利于催化剂活性的提高;镍基催化剂合适的焙烧温度为450℃;三氧化二镍合适的负载量为14%(质量分数);采用三氧化二镍负载量为14%并在焙烧温度为450℃条件下制备的镍基催化剂处理化学需氧量(COD cr)为6 000 mg/L的有机废水,当直接使用次氯酸钠处理有机废水时COD cr减小至5 554 mg/L,而加入镍基催化剂后在相同的反应时间内COD cr降为600 mg/L,且处理后的废水基本无色无味。

Supported Ni-based catalyst was prepared by immersion precipitation method with Al2O3/MgO as carrier.Prepared catalyst was characterized by BET,environmental scanning electronic microscope,and thermogravimetry and the catalytic performance thereof in decomposing sodium hypochlorite（NaClO） to produce active chlorine was also studied.Results showed that pore size distribution of Ni-based catalyst mainly concentrated in the mesopores,which was in favor of increasing catalytic activity;suitable calcination temperature for Ni-based catalyst was 450 ℃;proper loading amount of Ni2O3 was 14%（mass fraction）;Ni-based catalyst prepared under the above proper conditions was applied in dealing with organic wastewater whose CODcr was 6 000 mg/L.CODcr reduced to 5 554 mg/L when with the directly use of NaClO,whereas after the addition of Ni-based catalyst in the same reaction time,CODcr declined to 600 mg/L and wastewater was basically colorless and odorless after treatment.