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

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%。

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

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.