CN−的吸附行为及机理
(西安建筑科技大学 贵金属工程研究所，西安 710055)
摘 要: 研究铁氰溶液中D301树脂对Fe(Ⅲ)及CN−的吸附性能及过程的动力学和热力学参数。结果表明：25 ℃时，D301树脂(湿树脂)对Fe(Ⅲ)及CN−的饱和吸附量分别为2.173 49 mg/mL和28.963 2 mg/mL。吸附过程符合Lagergren二级速度方程，以液膜扩散为主控步骤。树脂对Fe(Ⅲ)及CN−的吸附速率方程分别为：t/Qt=0.057 1 t+2.415和t/Qt=0.427 9 t+4.572 1，吸附速率常数分别为k2=1.35 mL/(g∙min)和k2=39.9 mL/(g∙min)。热力学研究表明，吸附过程的焓变分别为： =16.78 J/mol， =11.07 J/mol，表明吸附过程是吸热过程。
关键字: 树脂；吸附；动力学；热力学
Fe(Ⅲ) and CN− in iron-cyanide solution
（Institute of Precious Metal Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China）
Abstract:The sorption properties of D301 resin for Fe(Ⅲ) and CN− were studied as well as dynamic parameter and thermodynamic parameter in the process. The static saturated adsorptive capacity of D301 resin on Fe(Ⅲ) and CN− is 2.173 49 mg/mL and 28.963 2 mg/mL, respectively, at 25 ℃. The sorption process accords with Lagergren-equation and the liquid film diffusion is the predominating step of the sorption process. The adsorption rate equations for CN− and Fe(Ⅲ) are t/Qt=0.057 1 t+2.415 and t/Qt=0.427 9 t+4.572 1, respectively. The adsorption rate constants for CN− and Fe(Ⅲ) are k2=1.35 mL/(g∙min) and k2=39.9 mL/(g∙min). The thermodynamic result indicates =16.78 J/mol and =11.07 J/mol. The sorption process is an endothermic process.
Key words: resin; adsorption; dynamics; thermodynamics
