纳米磁性颗粒Fe3O4用于吸附水相中酸性红73及其机理研究

Adsorption mechanism of acid red 73 onto magnetic nanoparticles Fe_3O_4 from aqueous phase

利用纳米磁性颗粒处理含酸性红73废水以利于进一步降低其色度.实验以酸洗废液制备的纳米磁粉Fe3O4作为吸附剂,并通过单因素实验和吸附动力学及热力学的分析探讨其对酸性红73的表面吸附的吸附机理.结果表明:纳米磁粉Fe3O4对酸性红73的表面吸附符合假二级动力学方程,其反应活化能为49.05 kJ·mol-1.磁粉对酸性红73的吸附是快速的表面物理吸附,其表面吸附行为符合Langmuir等温吸附式,是放热和熵减的自发过程.在温度T为303 K的条件下,20 min内的饱和吸附量能可达到40.1 mg·g-1.因此,用纳米磁粉Fe3O4吸附处理含偶氮染料废水,吸附平衡可在很短的时间内实现.

The present investigation focused on treating wastewater containing Acid Red 73( AR73) with nano-magnetic particle for further decolorization.In the experiments,nano-magnetic Fe3O4 particles prepared from pickling spent liquor were used as an adsorbent,and adsorption mechanism of AR73 on the surface of Fe3O4 was explored with the methods of single-factor experiments and adsorption-dynamic analysis. Results indicated that the adsorption of AR73 on the surface of nano-magnetic particles accorded well with the pseudo-second order kinetic equation with the reactive activation energy achieving49.05 kJ·mol-1. The adsorption of AR73 was a fast physical adsorption on the surface. Their behavior accorded with the Langmuir isothermal,and was a spontaneous,exothermic,and entropy-decreasing process. Under 303 K,the saturated adsorption capacity attained 40. 1 mg·g-1within 20 mins.Therefore,in terms of treating waste water containing azo dyes,the adsorption equilibrium could be achieved in a very short time.