School of Resource and Environmental Science, Wuhan University, 129 Luoyu Road, Wuhan 430079, PR China; ISTerre, Université Grenoble Alpes, P.O. Box 53, F 38041 Grenoble, France.
ISTerre, Université Grenoble Alpes, P.O. Box 53, F 38041 Grenoble, France.
Water Res. 2016 Sep 15;101:1-9. doi: 10.1016/j.watres.2016.05.032. Epub 2016 May 11.
We report on the synthesis and As adsorption properties of a novel chitosan - iron (oxyhydr)oxide composite material for the remediation of arsenic-contaminated water supplies. FE-SEM, Mössbauer spectroscopy, ICP-OES and synchrotron (Bulk XAS, μXRF) techniques were applied to determine the composition of the new material and investigate the As uptake efficiency and mechanism. The iron (oxyhydr)oxide phase has been identified as a nano-sized goethite, well dispersed in the chitosan matrix, leading to the name 'chitosan goethite bionanocomposite' (CGB). The CGB material is prepared in the form of beads of high density and excellent compression strength; the embedding of the goethite nanoparticles in the chitosan matrix allows for the high adsorption capacity of nanoparticles to be realized. CGB beads remove both As(III) and As(V) efficiently from water, over the pH range 5-9, negating the need for pre-oxidation of As(III). Kinetic studies and μXRF analysis of CGB bead sections show that diffusion-adsorption of As(V) into CGB beads is faster than for As(III). Using CGB beads, synthetic high-arsenic water (0.5 mg-As/L) could be purified to world drinking standard level (<0.01 mg-As/L) using only 1.4 g/L CGB. When considered in combination with the advantages of the low-cost of raw materials required, and facile (green) synthesis route, CGB is a promising material for arsenic remediation, particularly in developing countries, which suffer a diversity of socio-economical-traditional constraints for water purification and sanitation.
我们报告了一种新型壳聚糖-铁（氧氢）氧化物复合材料的合成及其对砷污染水源的吸附性能。采用 FE-SEM、穆斯堡尔光谱、ICP-OES 和同步辐射（体相 XAS、微 XRF）技术来确定新材料的组成，并研究砷的吸附效率和机制。确定了铁（氧氢）氧化物相为纳米级针铁矿，在壳聚糖基质中良好分散，从而得到“壳聚糖针铁矿生物纳米复合材料”（CGB）的名称。CGB 材料以高密度和优异压缩强度的珠粒形式制备；针铁矿纳米颗粒嵌入壳聚糖基质中，可实现纳米颗粒的高吸附容量。CGB 珠粒在 pH 值 5-9 范围内能有效去除水中的 As(III)和 As(V)，无需预先氧化 As(III)。CGB 珠粒的动力学研究和微 XRF 分析表明，As(V)扩散吸附到 CGB 珠粒中的速度快于 As(III)。使用 CGB 珠粒，只需 1.4 g/L 的 CGB 即可将含高砷的合成水（0.5 mg-As/L）净化至世界饮用水标准（<0.01 mg-As/L）。考虑到所需原材料成本低廉、合成路线简便（绿色）的优势，CGB 是一种很有前途的砷修复材料，特别是在发展中国家，这些国家在水净化和卫生方面受到各种社会经济传统限制的困扰。
