University of Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Faculty Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
J Environ Sci (China). 2019 Jun;80:240-247. doi: 10.1016/j.jes.2018.12.017. Epub 2019 Jan 2.
A method was developed for preparing high purity AlO(OH)(HO) (Al) through elimination of impurities by complexation. Polyaluminum chloride II (PAC) with Al content of 75% was adopted as the source of Al. The PAC was prepared under conditions of total aluminum concentration 0.1 mol/L and OH/Al ratio 2.2 to obtain the highest content of Al. A precipitation/metathesis method, organic solvent precipitation method and organic complexation method were examined to separate and purify Al. It was found that only by the organic complexation method could high purity Al products be obtained in large yield economically. In the experiments, benzoic acid was used as the coordinating reagent to decompose the main impurity AlOAl(OH)(HO) (Al), and the Al product could be obtained by precipitation and metathesis operations. It was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 hr. The Al product was characterized by Ferron assay, Al-NMR, SEM, XRD and TGA. The results showed that the purity of the Al product could exceed 92%.
通过络合去除杂质，开发了一种制备高纯度 AlO(OH)(HO)(Al)的方法。采用 Al 含量为 75%的聚合氯化铝 II (PAC) 作为 Al 的来源。在总铝浓度为 0.1 mol/L 和 OH/Al 比为 2.2 的条件下制备 PAC，以获得最高的 Al 含量。考察了沉淀/反相法、有机溶剂沉淀法和有机络合法来分离和纯化 Al。结果发现，只有通过有机络合法才能经济地获得高纯度 Al 产品。在实验中，使用苯甲酸作为配位试剂分解主要杂质 AlOAl(OH)(HO)(Al)，并通过沉淀和反相操作获得 Al 产物。值得注意的是，苯甲酸分解杂质可在 2 小时内完成。通过 Ferron 分析、Al-NMR、SEM、XRD 和 TGA 对 Al 产物进行了表征。结果表明，Al 产物的纯度可超过 92%。
