《Chemical Engineering Research and Design》杂志刊登“使用酸性氧化铝除氟”

作  者：Aparajita Goswami, Mihir K. Purkait

刊  物：《Chemical Engineering Research and Design》，2012年，90卷第12期，2316-2324页

关键词：氟化物；吸附；氧化铝；动力学；等温线

摘  要：氟化物被认为是饮用水中的一种主要无机污染物。氧化铝被用于去除水中多余的氟化物。目前研究表明，氧化铝在自然条件下为酸性，并且可认为是一种很好的氟化物去除吸附剂。吸附剂的标识值有XRD、SEM、BET和FTIR，其中氧化铝的BET表面积为144.27m²/g。在不同的试验参数条件下，如：接触时间、吸附剂质量、pH值、温度和搅拌速度，进行系统的吸附试验。氧化铝对氟化物的吸附量与pH值密切相关。PH值为4.4时，氟化物的去除效果最佳。过低和过高的pH值均对除氟效率有一定的影响。热力学参数研究表明，物理吸附是由95.13kJ/mol的活化能和吸热过程所主导控制的。动力学研究表明，该吸附过程符合伪二级动力学方程。使用朗缪尔和弗伦德里希等温线模型研究此吸附平衡。该吸附过程符合朗缪尔等温线模型，吸附容量为8.4mg/g。为了吸附材料的重复使用本文提出了一种再生研究，以提高吸附过程的经济性。最终，确定一种计算从水介质中有效去除氟化物需求吸附剂量的设计过程。

The defluoridation of water by acidic alumina

Authors: Aparajita Goswami, Mihir K. Purkait

Journal: Chemical Engineering Research and Design, Volume 90, Number 12 (2012), 2316-2324

Key words: Fluoride; Adsorption; Alumina; Kinetics; Isotherm

Abstract: Fluoride is considered as a major inorganic pollutant present in drinking water. To remove this excess fluoride, defluoridation was done by alumina. In the present study, alumina used was acidic in nature and hence considered as a good fluoride removing adsorbent. Characterization of the adsorbent was done by XRD, SEM, BET and FTIR with BET surface area of 144.27 m²/g. Systematic adsorption experiments were carried out with different process parameters such as contact time, adsorbent mass, pH, temperature and stirring speed. Fluoride adsorption by alumina was highly pH dependent. Maximum fluoride was removed from water at pH 4.4. At very low and very high pH, fluoride removal efficiency was affected. The study of thermodynamic parameters inferred that physical adsorption was dominant with activation energy of 95.13 kJ/mol and endothermic behavior of the process. The kinetics study concluded that pseudo second order kinetics was followed by the adsorption process. Adsorption equilibrium was studied with Langmuir and Freundlich isotherm models. The adsorption process followed Langmuir isotherm with an adsorption capacity of 8.4 mg/g. A regeneration study was proposed in order to reuse the adsorbent for better economy of the process. Finally, a process design calculation was reported to know the amount of adsorbent required for efficient removal of fluoride from aqueous medium.

原文链接：http://www.sciencedirect.com/science/article/pii/S0263876212001736