(浙江工商大学 应用化学系,杭州 310035)
摘 要: 研究用D113弱酸性树脂吸附锌(Ⅱ)的过程。结果表明:D113树脂对锌离子的吸附在pH=6.20的HAc-NaAc介质中最佳,每克树脂在298 K下静态饱和吸附容量为172 mg;用2~3 mol/L的盐酸溶液进行洗脱,一次洗脱率可达100%。不同温度下,树脂吸附锌的表观吸附速率常数分别为:k288 K=1.82×10−5/s、k298 K=2.34×10−5/s、k308 K=2.81×10−5/s、k313 K=3.26×10−5/s;表观吸附活化能Ea=17.0 kJ/mol。测得热力学参数分别为:∆H=30.3 kJ/mol,∆S=160 J/(mol·K),∆G=−17.4 kJ/mol;等温吸附服从Freundlich和Langmuir经验式。
关键字: 弱酸性树脂;锌;吸附;热力学;动力学
(Department of Applied Chemistry, Zhejiang Gongshang University, Hangzhou 310035, China)
Abstract: The sorption of Zn(Ⅱ) with macroporous weak acid resin (D113 resin) was investigated. The results show that D113 resin has a good sorption ability for Zn(Ⅱ) at pH=6.20 in the HAc-NaAc medium. The statically saturated sorption capacity is 172 mg per gram of resin at 298 K. Zn(Ⅱ) adsorbed on D113 resin can be eluted by using over a range of 2.0−3.0 mol/L HCl quantitatively. The sorption rate constants are k288 K=1.82×10−5/s, k298 K=2.34×10−5/s, k308 K= 2.81×10−5/s, k313 K= 3.26×10−5/s, respectively. The apparent activation energy is 17.0 kJ/mol. The sorption parameters of thermodynamic are ∆H=30.3 kJ/mol, ∆S=160 J/(mol•K) and ∆G298 K=−17.4 kJ/mol, respectively. The sorption behavior of D113 resin for Zn(Ⅱ) obeys the Freundlich and the Langmuir isotherms.
Key words: weak acid resin; zinc; sorption; thermodynamics; kinetics