摘要
在高盐废水浓缩减量过程中,残余的Ca(Ⅱ)容易形成碳酸钙和硫酸钙沉淀,影响膜浓缩系统的长期稳定运行。本文采用静态吸附系统研究了Amberlite IRC 747、Letwatit TP 260和D113 3种离子交换树脂对高盐废水中残余Ca(Ⅱ)的吸附规律。结果表明:延长接触时间和升高反应温度,3种离子交换树脂的吸附量均会上升,而提高含盐量则会显著抑制Ca(Ⅱ)的吸附;Langmuir等温线比Freundlich等温线的拟合结果更好,IRC 747、TP 260和D113的理论最大吸附量分别为81.43、75.08、109.17 mg/g;离子交换树脂对Ca(Ⅱ)的吸附过程符合拟二级动力学,初始反应速率大小顺序为IRC 747>D113>TP 260;离子交换反应的吉布斯自由能变化(?G_o)、焓变(?H_o)、熵变(?S_o)和活化能(E_a)等热力学参数表明,3种离子交换树脂对Ca(Ⅱ)的吸附有效,属于吸热反应,且反应可以自发进行。
During the process of concentration and minimization of high salinity wastwater, residual Ca（Ⅱ）easily forms calcium carbonate and calcium sulfate precipitates, which affects the long-term stable operation of the membrane concentration system. In this study, the adsorption mechanism of residual Ca（Ⅱ） from high salinity wastwater by Amberlite IRC 747 ion exchange resin, Letwatit TP 260 ion exchange resin and D113 ion exchange resin is studied by static adsorption system. The results show that, the adsorption capacities of three ion exchange resins increases as the contact time is prolonged and the reaction temperature is increased, while increasing the salt content prohibits the adsorption of Ca（Ⅱ）. Besides, Langmuir isotherms are fitted better than Freundlich isotherms, and the theoretical maximum adsorption capacities of IRC 747, TP 260 and D113 are 81.43 mg/g,75.08 mg/g and 109.17 mg/g, respectively. The adsorption of Ca（Ⅱ） by ion exchange resins is in accordance with the pseudo-second-order kinetics, the order of initial reaction rate is IRC 747 〉D113 〉TP 260. In addition, the thermodynamic parameters such as Gibbs free energy change（△G_o）, enthalpy change（△H_o）, entropy change（△S_o）and activation energy（E_a） of the ion exchange reaction reveals that the adsorption of Ca（Ⅱ） by these three ion exchange resins is effective, endothermic and spontaneous.
作者
张弦
叶春松
黄建伟
刘通
ZHANG Xian;YE Chunsong;HUANG Jianwei;LIU Tong(School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,Chin)
出处
《热力发电》
CAS
北大核心
2018年第8期66-72,共7页
Thermal Power Generation
基金
国家自然科学基金项目(51602228)~~
关键词
高盐废水
离子交换树脂
Ca(Ⅱ)
静态吸附法
等温线
动力学
热力学
high salinity wastewater
ion exchange resin
Ca（II）
static adsorption method
isotherms
kinetics
thermodynamics
