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采用电弧放电法制备了Zn O/C纳米球,利用FESEM、XRD和N2吸附/脱附测试进行了表征。在避光条件下研究了复合材料对亚甲基蓝的吸附性能。研究结果表明,随着亚甲基蓝的浓度及接触时间的增长吸附量明显上升,在吸附时间为150 min时达到吸附平衡。采用Langmuir、Freundlich及Temkin等温吸附模式对吸附平衡进行了研究。结果表明,吸附等温线符合Langmuir等温吸附模式,单层吸附饱和容量可达188.68 mg·g-1。利用动力学模型、内扩散模型和外扩散速率控制模型拟合实验数据,拟合数据表明其动力学符合伪二级动力学模型;内扩散机理不是吸附速率的唯一限制机理,亚甲基蓝的总吸附速率受膜扩散控制。
The Zn O / C nanospheres were prepared by arc discharge method and characterized by FESEM, XRD and N2 adsorption / desorption tests. The adsorption of methylene blue on the composites was studied under dark conditions. The results showed that with the increase of methylene blue concentration and contact time, the adsorption capacity increased obviously, and the adsorption equilibrium reached at 150 min. Adsorption equilibrium was studied by Langmuir, Freundlich and Temkin adsorption isotherms. The results showed that the adsorption isotherms fit the Langmuir isothermal adsorption model, and the monolayer adsorption saturation capacity can reach 188.68 mg · g-1. The kinetic model, internal diffusion model and external diffusion rate control model were used to fit the experimental data. The fitting data showed that the kinetic model was in accordance with the pseudo second-order kinetic model. The internal diffusion mechanism was not the only restriction mechanism of adsorption rate. The total adsorption rate of methylene blue Diffusion-controlled by the membrane.