Souza Isis P A F, Cazetta André L, Pezoti Osvaldo, Almeida Vitor C
Laboratory of Environmental and Agrochemistry, Department of Chemistry, Universidade Estadual de Maringá, Av. Colombo 5790, Maringá, Paraná, 87020-900, Brazil.
Environ Monit Assess. 2017 Nov 12;189(12):632. doi: 10.1007/s10661-017-6330-7.
In this study, the biosorption properties of Jatoba (Hymenaea courbaril) fruit shell for removal of Pb(II) and Cd(II) ions from aqueous solutions, and its potential as a low-cost biosorbent for water treatment, were investigated. The Jatoba fruit shell (JB) was subjected to different treatments with heated water (JB) and sodium hydroxide (JB) to modify its surfaces and improve its adsorption properties. The chemical modification of the surfaces of the resulting materials was confirmed by analyzing the compositions and structural features of the raw material and the chemically treated materials using SEM, FTIR, C NMR, and pH. The ability of the biosorbents to remove the metal ions was investigated with batch adsorption procedures. The adsorption data were then examined in detail by applying adsorption models of Langmuir, Freundlich, and Dubinin-Radushkevich. The results showed that the experimental data were best described by the Langmuir model for the Pb-JB and Cd-JB systems, the Freundlich model for the Pb-JB and Pb-JB systems, and the Dubinin-Radushkevich model for Cd-JB and Cd-JB systems. The maximum adsorption capacities of JB obtained using the Langmuir model reached values of 30.27 and 48.75 mg g for Cd(II) and Pb(II), respectively. The adsorption kinetic studies showed that the pseudo-second-order model was the best fitted to the experimental data, and adsorptions for Pb-JB and Cd-JB are controlled by intraparticle diffusion mechanism.
本研究考察了孪叶苏木（Hymenaea courbaril）果壳从水溶液中去除Pb(II)和Cd(II)离子的生物吸附特性及其作为低成本水处理生物吸附剂的潜力。对孪叶苏木果壳（JB）进行了热水（JB）和氢氧化钠（JB）的不同处理，以改性其表面并改善其吸附性能。通过使用扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、碳核磁共振（C NMR）和pH值分析原材料及化学处理材料的组成和结构特征，证实了所得材料表面的化学改性。采用分批吸附程序研究了生物吸附剂去除金属离子的能力。然后通过应用朗缪尔（Langmuir）、弗伦德利希（Freundlich）和杜比宁-拉杜舍维奇（Dubinin-Radushkevich）吸附模型详细考察了吸附数据。结果表明，对于Pb-JB和Cd-JB体系，实验数据最符合朗缪尔模型；对于Pb-JB和Pb-JB体系，最符合弗伦德利希模型；对于Cd-JB和Cd-JB体系，最符合杜比宁-拉杜舍维奇模型。使用朗缪尔模型获得的JB对Cd(II)和Pb(II)的最大吸附容量分别达到30.27和48.75 mg g。吸附动力学研究表明，准二级模型最符合实验数据，Pb-JB和Cd-JB的吸附受颗粒内扩散机制控制。
