【摘要】 根据配位化学热力学平衡原理,绘制了Cd2+-H2O系配合离子浓度pc—pH图、镉羟合配离子分率αn—pH图及Cd(OH)2条件溶度积pKS—pH图。pc—pH图描述了Cd(OH)2(s)溶解平衡时,镉的总离子平衡浓度与pH的关系。当pH为9.84～13.31时,Cd(OH)2的溶解度最小;αn—pH图指出了各种羟合配离子分率与pH关系,每种羟合配离子都对应有其存在的最佳pH范围。Cd(OH)2(s)的条件溶度积pKS—pH图表明:当pH值在9.5～10.5范围内,Cd(OH)2(s)的条件溶度积最小。研究结果可为中和水解法去除废水中镉等技术提供理论依据。更多还原

【Abstract】 The diagrams for the concentration of complex ions pc—pH,the ratio of cadmium hydroxy complex ions αn—pH and the conditional solubility product of Cd(OH)2 to pH value in Cd2+-H2O system were drawn,respectively.The relationship between the equilibrium concentration of total cadmium ions and pH value was shown in Cd2+-H2O system,when the dissolution of Cd(OH)2 is in equilibrium.The solubility of Cd(OH)2 is the least at pH value of 9.84-13.31.The diagram for pKS—pH shows that each hydroxy complex ion existing in this system is dependent upon an optimized pH value.The diagram for the conditional solubility product pKS—pH indicates that the pKS reaches the minimum value at pH value ranging from 9.5 to 10.5.The results can provide a theoretical basis for the technology on removal of cadmium ion from the wastewater by neutralized hydrolyzation method.更多还原