三聚磷酸二氢铝对水中铜离子的吸附动力学

采用离子交换吸附法研究三聚磷酸二氢铝吸附水中铜离子的动力学行为和吸附活化状态热力学参数分析。结果表明:三聚磷酸二氢铝对水溶液中铜离子的化学吸附是二级反应,吸附速率常数k与温度T之间的关系符合阿仑尼乌斯式,吸附的活化能为Ea=56.35kJ/mol,吸附的频率因子A=2.5×106L/(mg·min),ln(k/T)与1/T之间的关系符合Eyring公式,其活化焓ΔH=53.21kJ/mol,活化熵ΔS=-153.36J/(mol·K),同时k与铜离子初始浓度呈负相关性,与三聚磷酸二氢铝用量呈正相关性,介质pH=5时有利于吸附。

Adsorption Kinetics of Aqueous Copper on Aluminum Dihydrogen Tripolyphosphate

Dynamics of adsorption and thermal dynamic parameters for copper ion in water phase using aluminum dihydrogen tripolyphosphate were studied by ion exchange absorption method.Results showed that the absorption of copper ion on aluminum dihydrogen tripolyphosphate satisfied second order reaction kinetics equation.The relationship between reaction rate constant and temperature was in accordance with Arrhenius equation,with activation energy of absorption 56.35kJ/mol and frequency factor 2.5×106 L/(mg·min).Relationship between ln(k / T)and l/T was in accordance with Eyring equation,with activation enthalpy of absorption 53.21 kJ/mol and activation entropy of absorption-153.36 J/(mol·K).Reaction rate constant increased with decrease of Cu initial concentration,and increased with increase of dosage of aluminum dihydrogen tripolyphosphate.Medium pH of 5 was advantageous to the adsorption.