焙烧态镁铝水滑石去除水中磷酸根的研究

采用液相双滴共沉淀法制备镁铝水滑石,在350℃下焙烧成为焙烧态水滑石(CHTlc-350)样品。采用XRD、FT—IR对样品进行分析,研究了CHTlc-350对磷酸根的吸附特性;探讨了时间、pH、吸附剂投加量对吸附磷酸根性能的影响。结果表明,当初始pH为5,吸附剂与溶液接触24 h时,CHTlc-350对磷酸根的吸附效果最佳。CHTlc-350对磷酸根的吸附符合Langmuir吸附等温线和伪二级动力学模型;其最大理论吸附量达到90.09 mg/g。CHTlc-350可有效去除废水中的磷酸根,磷浓度为40 mg/L,吸附剂浓度为1.0 g/L时,其去除率可达99.44%。

Research on the removal of phosphate by calcined Mg/Al Hydrotalcite-like compounds in aqueous solutions

Mg/Al hydrotalcite-like compounds (HTlcs) were synthesized by the coprecipitiation method, and CHTlc-350 was obtained by calcing the HTlcs at 350oC. The samples were examined by X-Ray diffraction (XRD) and Foutier transform infrared (FTIR) spectroscopy. Effects of the main factors on the adsorption of phosphate on CHTlc-350 were studied. It was found that CHTlc-350 has a good adsorption when the initial pH was approximately 5 and it took 24h to reach equilibrium. The experimental data were consistent with Langmuir isotherm model and pseudo-second-order kinetics, the theoretical maximum adsorption amount of phosphate was up to 90.09mg/g. CHTlc-350 showed a high adsorption capacity for phosphate. The percentage of removal reached 99.44% with phosphate concentration of 40mg/L and adsorbent dose of 1.0g/L.