Zhang Ying, Zheng Ru, Zhao Jiaying, Ma Fang, Zhang Yingchao, Meng Qingjuan
School of Resource and Environment, Northeast Agricultural University, Harbin 150030, China ; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
School of Resource and Environment, Northeast Agricultural University, Harbin 150030, China.
Biomed Res Int. 2014;2014:496878. doi: 10.1155/2014/496878. Epub 2014 Feb 11.
Rice husk, a surplus agricultural byproduct, was applied to the sorption of copper from aqueous solutions. Chemical modifications by treating rice husk with H3PO4 increased the sorption ability of rice husk for Cu(II). This work investigated the sorption characteristics for Cu(II) and examined the optimum conditions of the sorption processes. The elemental compositions of native rice husk and H3PO4-treated rice husk were determined by X-ray fluorescence (XRF) analysis. The scanning electron microscopic (SEM) analysis was carried out for structural and morphological characteristics of H3PO4-treated rice husk. The surface functional groups (i.e., carbonyl, carboxyl, and hydroxyl) of adsorbent were examined by Fourier Transform Infrared Technique (FT-IR) and contributed to the adsorption for Cu(II). Adsorption isotherm experiments were carried out at room temperature and the data obtained from batch studies fitted well with the Langmuir and Freundlich models with R (2) of 0.999 and 0.9303, respectively. The maximum sorption amount was 17.0358 mg/g at a dosage of 2 g/L after 180 min. The results showed that optimum pH was attained at pH 4.0. The equilibrium data was well represented by the pseudo-second-order kinetics. The percentage removal for Cu(II) approached equilibrium at 180 min with 88.9% removal.
稻壳，一种过剩的农业副产品，被用于从水溶液中吸附铜。用磷酸处理稻壳进行化学改性提高了稻壳对Cu(II)的吸附能力。这项工作研究了对Cu(II)的吸附特性，并考察了吸附过程的最佳条件。通过X射线荧光（XRF）分析确定了天然稻壳和经磷酸处理的稻壳的元素组成。对经磷酸处理的稻壳进行了扫描电子显微镜（SEM）分析以研究其结构和形态特征。通过傅里叶变换红外技术（FT-IR）检测了吸附剂的表面官能团（即羰基、羧基和羟基），这些官能团有助于对Cu(II)的吸附。在室温下进行了吸附等温线实验，从批次研究中获得的数据分别与朗缪尔模型和弗伦德利希模型拟合良好，相关系数R²分别为0.999和0.9303。在180分钟后，当投加量为2 g/L时，最大吸附量为17.0358 mg/g。结果表明，最佳pH值为4.0。平衡数据用准二级动力学能很好地表示。Cu(II)的去除率在180分钟时接近平衡，去除率为88.9%。
