高浓度聚合氯化铝的合成及其形态分布与转化规律

以CaO为碱化剂采用一次加碱法合成了高浓度聚合氯化铝(PAC),研究了其反应特性及产品的铝形态分布与转化规律.结果表明,CaO特殊的水化反应可使PAC达到较高浓度和较高B值,PAC最高浓度可达2.1mol/L,B值为2.1.合成过程中无论高铝浓度体系还是低铝浓度体系,均存在一最佳B值,此B值下产品的Al_b含量最高.最佳B值和最高Al_b含量均随总铝浓度的升高而降低.B值小于最佳B值时,总反应主要表现为生成Al_b;B值大于最佳B值时,总反应表现为生成Al_c.

Synthesis of High-Concentration Polyaluminum Chloride and Its Aluminium Species Distribution and Transformation

Using solid CaO as basification agent, the high concentration polyaluminum chloride (PAC) was prepared by feeding total alkali at a time. The characteristics of the reaction and the distribution and transformation of the aluminium species were also studied. The experimental results show that the distinctive hydration of CaO can contribute to the high concentration PAC whose Al concentration (Al_T) and basicity (B) can reach 2.1 mol/L and 2.1 respectively. There is an optimal B value in any concentration of PAC, at which the Al_b content is the highest. The optimal B value and the highest Al_b content drops with the increasing of Al_T. The predominant reaction is the formation of Al_b if B is less than the optimal B value, and the formation of Al_c if B is more than the optimal B value.