明胶固化硫脲微粒对Ag~+的吸附及其热力学研究

以明胶和硫脲为原料,戊二醛为交联剂,采用反相悬浮聚合得到了明胶固化硫脲微粒(TIGM),研究了其对水溶液中Ag+的静态吸附分离及热力学性质。结果表明,TIGM对Ag+吸附平衡数据符合Langmuir和Freundlich吸附等温方程,且Ag+在微粒吸附过程中表现为优惠吸附。Freundlich吸附等温线和热力学研究表明,在283～323K条件下,Ag+吸附量为0.07～0.10mmol/g时,反应的吸附焓变为28.42～31.73kJ/mol,表明该吸附反应是吸热过程,升高温度有利于反应的进行;吸附自由能变为负值,表明常温下该吸附是自发的过程;吸附熵变为111.14～129.70J/mol·K,表明该吸附是个熵增的过程。

Adsorption of Ag+ on Thiourea Impregnated Gelatin Microspheres and Thermodynamic Analysis

Thiourea impregnated gelatin microspheres (TIGM) were synthesized from gelatin and thiourea by inverse suspension polymerization with glutaraldehydeaether as crosslinker.The adsorption and thermodynamic behavior of Ag+ in aqueous solution on TIGM was investigated by static method.Results indicated that the process of absorption fit well with both classical Langmuir and Freundlich equation.The study of Freundlich adsorption isotherms and thermodynamics showed that when adsorption of Ag+ were 0.07～0.10mmol/g in 283～323K,adsorption enthalpy change was 28.42～31.73kJ/mol,free energy was-5.496～4.697kJ/mol and entropys of adsorption was 111.14～129.70J/mol·K.