College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006, PR China.
J Hazard Mater. 2010 Apr 15;176(1-3):650-6. doi: 10.1016/j.jhazmat.2009.11.081. Epub 2009 Dec 16.
This paper describes the adsorption of cadmium ions from aqueous solution using acrylonitrile (AN)-modified corn stalk (AMCS). AMCS was characterized by elemental analysis, scanning electron microscopy, surface area and porosity analyzer, Fourier transform infrared and solid-state CP/MAS (13)C NMR spectra, and then used to evaluate the adsorption capacity in different pH values, adsorption isotherm, kinetics and thermodynamics in batch experiments. The results showed that AMCS is found to be an effective adsorbent because of its pore size and functional groups (-CN). The pH of 7.0 was an optimal pH for removal of Cd(II) ion and the Langmuir model provides a better fit to the equilibrium data than the Freundlich model, showing a maximum uptake of 12.73 mg g(-1), compared to raw corn stalk (RCS) (3.39 mg g(-1)). Analysis indicated that pseudo-second-order kinetics controlled the adsorption rate. The activation energy (E(a)) was 9.43 kJ mol(-1). Thermodynamic parameters such as DeltaG, DeltaH and DeltaS were also evaluated to predict the nature of adsorption process.
本文描述了用丙烯腈（AN）改性的玉米秸秆（AMCS）从水溶液中吸附镉离子。通过元素分析、扫描电子显微镜、比表面积和孔隙度分析仪、傅里叶变换红外和固态 CP/MAS（13）C NMR 光谱对 AMCS 进行了表征，然后用于评估批实验中不同 pH 值、吸附等温线、动力学和热力学条件下的吸附能力。结果表明，由于其孔径和官能团（-CN），AMCS 是一种有效的吸附剂。去除 Cd(II)离子的最佳 pH 值为 7.0，Langmuir 模型比 Freundlich 模型更能拟合平衡数据，最大吸附量为 12.73mg g(-1)，而原玉米秸秆（RCS）的吸附量为 3.39mg g(-1)。分析表明，吸附速率受准二级动力学控制。活化能（E(a)）为 9.43kJ mol(-1)。还评估了热力学参数（如ΔG、ΔH 和ΔS），以预测吸附过程的性质。
