累托石/腐殖酸微球对水中Cd~(2+)的吸附及动力学研究

采用累托石、腐殖酸、海藻酸钠、氯化钙和聚乙烯醇等材料制备微球状吸附剂去除水中镉离子。考察了微球用量、吸附时间、pH值等因素对吸附效果的影响,测定了吸附等温线,对吸附动力规律进行了探讨。结果表明,在本研究条件下,微球用量、温度和吸附时间对水中镉离子的吸附效果有显著性影响,但溶液pH值对吸附效果的影响并不显著。最优吸附条件为:温度25℃、溶液pH为6,吸附时间6h、微球用量为0.025g/mL。等温吸附规律可用Freundlich和Langmuir模式较好地模拟,吸附呈单分子层形式,吸附性能良好,吸附易于进行。吸附动力学规律遵循Lagergren准一级和Elovich动力学模型。

Kinetics Study on Adsorption of Cd2+ in Water on Rectorite/Humic Acid Microspheres

Rectorite(REC),humic acid(HA),polyvinyl alcohol(PVA),sodium alginate(SA)and calcium chloride were used to prepare microspheres adsorbent to remove Cd2+ from water. The effects of microspheres dosage,shaking time and pH on adsorption efficiencies were investigated. Adsorption isotherms were determined and adsorption kinetics law was discussed. Results showed that microspheres dosage,temperature and shaking time has remarkably influence on adsorption efficiency respectively while pH of Cd2+ solution has not obvious influence on adsorption. The optimum adsorption conditions were temperature 25℃,pH 6,shaking time 6h and microspheres dosage 0.025g/mL. The law of isothermal adsorption can be well described by Freundlich and Langmuir models. The adsorption kinetics conform to Lagergren and Elovich models.