“类龟式”Al_(13)盐酸盐的制备及絮凝性能

MULTI-APPROACHES PREPARATION AND FLOCCULATION PERFORMANCE STUDY OF CHLORIDE CRYSTALS OF TORTOISE LIKE Al_(13)

采用氯化铝溶液电解法、氯化铝溶液溶铝法、稀盐酸溶铝法、氯化铝溶液碱性阴离子树脂交换法、氯化铝溶液补水蒸馏法、氯化铝溶液压溶氢氧化铝或氧化铝法等促使氯化铝水解-聚合的方法,通过控制起始溶液的浓度、水解-聚合的程度和体系的温度,制成“类龟式”Al13含量超过96·5%的聚合氯化铝结晶,其中电解法制备的产物纯度达99·9%,盐基度61·48%,总铝(Al2O3)33·75%,水不溶物0·01%,Alb达97%.化学分析、X-射线粉末衍射和X-射线单晶结构解析结果表明,产物是一种由十三个铝氧八面体连接组成的Al13(OH)24Cl15·37H2O化合物.高岭土模拟水样和黄河水样絮凝试验表明,絮凝效果优于市售固体聚合氯化铝、氯化铝和硫酸铝,经絮凝处理的黄河水主要水质质量指标达到国家生活饮用水标准GB5749-85的要求.

Chloride crystals of ＂tortoise like＂ Al13 （its content is higher than 96. 5% ）was prepared using various methods causing hydrolysis and polymerization of Al^3＋ ion, including electrolyzing AlCl3 solution, dissolving Al into hot AlCl3 solution or dilute HCl, exchanging AlCl3 solution with basic anion resin, distilling AlCl3 solution by adding water simultaneously, and dissolving AI（OH）3 or Al2O3 into hot AlCl3 solution under pressure, by controlling the concentration of initial AlCl3 or HCl solution, the degree of hydrolysis and polymerization, and the temperature of system. Among these methods, main quality indexes of the product prepared by electrolyzing are 99. 9% on purity, 61.48% on basicity, 33. 75% on Al2O3 content, 0. 01% on water insoluble substance, and 97% on key flocculating component（Alb ）, respectively. Chemical composition, XRD and crystal structure analyses have proved that the product is a compound linked by 13 AlO6 octahedra with Al13 （OH）24Cl15·37H2O. The results of flocculating test on simulant turbid water by adding Kaolin and Yellow river water indicate that flocculating performance of the product is more excellent than industrial PAC, AlCl3·6H2O and Al2 （ SO4 ） 3·18H2O obviously. After treatment, main quality indexes of Yellow river water achieved the requirements of national standard of China for potable water in number GB5749-85, the residual Al content is infinitesimal. As a promising high efficiency flocculant, it＇ s important for saving limited groundwater resources by using Yellow river water and treating waste water.