| 高效磷吸附剂Mg/Al-LDO的制备及除磷机制 |
| 摘要点击 3995 全文点击 1298 投稿时间：2016-06-27 修订日期：2016-09-04 |
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| 中文关键词 磷吸附剂 Mg/Al-LDO 制备条件 吸附特性 吸附机制 |
| 英文关键词 phosphorous adsorbent Mg/Al-LDO synthesis conditions adsorption characteristics adsorption mechanism |
| 作者 | 单位 | E-mail | | 王卫东 | 北京工业大学建筑工程学院, 北京市水质科学与水环境恢复工程重点实验室, 北京 100124 | 814836382@qq.com | | 郝瑞霞 | 北京工业大学建筑工程学院, 北京市水质科学与水环境恢复工程重点实验室, 北京 100124 | haoruixia@bjut.edu.cn | | 张晓娴 | 北京工业大学建筑工程学院, 北京市水质科学与水环境恢复工程重点实验室, 北京 100124 | | | 万京京 | 北京工业大学建筑工程学院, 北京市水质科学与水环境恢复工程重点实验室, 北京 100124 | | | 钟丽燕 | 北京工业大学建筑工程学院, 北京市水质科学与水环境恢复工程重点实验室, 北京 100124 | |
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| 中文摘要 |
| 针对污水中磷的去除问题，采用优化后的恒定pH值共沉淀法制备了Mg/Al-layered double hydroxides（Mg/Al-LDHs），经高温焙烧得到高效磷吸附剂Mg/Al-layered double oxide（Mg/Al-LDO）；在对其吸附特性研究的基础上，并结合Zeta电位、XRD、FTIR分析吸附前后材料等电点、晶体结构及层间阴离子的变化，探讨Mg/Al-LDO吸附除磷机制.结果表明，采用优化后的共沉淀法，在Mg/Al比为2：1，焙烧温度450℃，焙烧时间2 h条件下制备出的Mg/Al-LDO对磷酸根吸附性最好，最大吸附容量可达到176.94 mg·g-1，与理论吸附容量191.57 mg·g-1基本一致，远高出Mg/Al-LDHs及其它磷吸附剂.实验数据对准二级反应动力学模型的拟合结果较好，吸附过程符合Langmuir吸附等温模型.结合Zeta电位、XRD、FTIR的结果推测，Mg/Al-LDO吸附除磷主要是通过静电引力、阴离子插层、离子交换、表面配位这4种作用协同完成. |
| 英文摘要 |
| Aiming at the problem of phosphorus removal in water, Mg/Al-layered double hydroxides (Mg/Al-LDHs) were synthesized via optimized constant pH co-precipitation method, and highly efficient phosphorus adsorbent Mg/Al-layered double oxide(Mg/Al-LDO) was obtained when it was calcined at high temperature. Based on the adsorption characteristics of phosphorus removal, the study combined Zeta potential, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) to analyze the changes of isoelectric point, crystal structure and functional group before and after adsorption. In addition, Mg/Al-LDO of phosphorus adsorption mechanism was discussed. The results indicated that using the optimized co-precipitation method in the conditions of Mg/Al=2:1, calcination temperature 450℃, and calcination time 2 h, the Mg/Al-LDO adsorption capacity of phosphate was the best, and the maximum adsorption capacity could reach 176.94 mg·g-1, which was basically consistent with the theoretical adsorption capacity of 191.57 mg·g-1, far higher than those of Mg/Al-LDHs and other phosphorus adsorbents. The results showed that the experimental data has the best fitting result with pseudo-second-order kinetics model. The adsorption process was consistent with Langmuir adsorption isotherm model. The results of Zeta potential, XRD and FTIR showed that phosphorus adsorption of Mg/Al-LDO was accomplished co-operatively by electrostatic attraction, anion in layer, ions exchange, and surface co-ordination. |
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