高岭土负载纳米铁镍双金属去除水中偶氮染料直接耐晒黑G

Removal of Direct Black G in aqueous solution using kaolin supported Fe-Ni nanoparticles

采用液相还原法制备焙烧高岭土负载纳米铁镍双金属(CK-Fe/Ni)。考察了在不同条件下,如pH、投加量、初始浓度、温度等,对负载型纳米铁镍双金属降解水中偶氮染料直接耐晒黑G的影响及动力学研究。结果表明:在pH=9.49、温度为30℃、负载型纳米铁镍双金属的投加量为1.05 g/L、搅拌速度为60 r/min,经过20 min反应后,负载型纳米铁镍双金属降解水中偶氮染料直接耐晒黑G的去除率达到了99.98%。吸附和电镜表征结果表明,作为载体的焙烧高岭土起着吸附直接耐晒黑G和分散纳米铁镍双金属颗粒的作用导致反应活性提高。降解动力学数据表明,负载型纳米铁镍双金属对直接耐晒黑G的降解过程符合伪一级反应动力学规律,速率常数k随负载型纳米铁镍双金属的投加量的增加而提高,表观活化能为19.72 kJ/mol。最后,利用高岭土负载纳米铁镍双金属对废水处理,结果表明,负载型纳米铁镍双金属在实际废水中对直接耐晒黑G的去除率达到了99.98%。

Calcinated kaolin supported iron-nickel bimetallic nanoparticles（CK-Fe/Ni） was synthetized and used for the degradation of azo dye Direct Black G（DBG）.The parameters affecting the degradation of DBG such as solution pH,dosage,initial concentration of DBG and temperature were investigated.Results show that the 99.98% of DBG in aqueous solution was removed after 20 minutes using CK-Fe/Ni at pH of 9.49,303 K and 1.05 g/L of CK-Fe/Ni.In addition,batch experiments and scanning electron microscopy（SEM） show that the presence of calcinated kaolin led to adsorb the DBG on the calcinated kaolin,as well as a decrease in aggregation of Fe/Ni nanoparticles and a corresponding increase in the reactivity.The kinetics show that the degradation process of DBG fits well the pseudo-first-order kinetics,and the rate constant increases with the increasing dosage of CK-Fe/Ni with Ea=19.72 kJ/mol.Finally,the degradation of wastewater using CK-Fe/Ni indicates that the 99.98% of DBG was removed.