Wu Chung-Hsin, Lin Cheng-fang, Chen Wan-Ru
Department of Environmental Engineering and Health, Yuanpei University of Science and Technology, Hsinchu, Taiwan, ROC.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2004;39(3):717-28. doi: 10.1081/ese-120027737.
This study applies sintering technology to convert water sludge to a useful and stable adsorption material. The properties of the sintered materials were characterized using SEM and BET. Additionally, adsorption experiments were conducted to elucidate interactions of Cr(III) and Hg(II) at the interface between water and sintered material. Elemental analysis of original water sludge indicates its main constituents to be SiO2 (54%), Al2O3 (21%), and Fe2O3 (6.6%). The BET measurement indicated that the specific surface area of the sintered material is 4.6 m2/g. Since the SiO, content exceeds 50%, the surface of the sintered material becomes negatively charged. Adsorption of Cr(III) and Hg(II) on sintered material shows that sorption depends on the systems' pH. The sorption densities are 1.40 mg Cr/g at equilibrium pH 4.6 and 0.43 mg Hg/g at equilibrium pH 6.0. Background electrolyte does not affect the sorption of Cr(III) but markedly affects the sorption of Hg(II). The affinity of Cr(III) for surface reacting sites seem to exceed that of Hg(II). Competitive adsorption experiments were performed to determine the magnitude of the variations in adsorption due to competitive interactions among Cr(III) and Hg(II). The experimental results indicate that a higher competitive solute concentration results in a more significant competitive effect on Hg(II).
本研究应用烧结技术将水污泥转化为一种有用且稳定的吸附材料。采用扫描电子显微镜（SEM）和比表面积分析仪（BET）对烧结材料的性能进行了表征。此外，还进行了吸附实验，以阐明水与烧结材料界面处铬（III）和汞（II）的相互作用。对原始水污泥的元素分析表明，其主要成分是二氧化硅（SiO₂，54%）、氧化铝（Al₂O₃，21%）和氧化铁（Fe₂O₃，6.6%）。BET测量表明，烧结材料的比表面积为4.6平方米/克。由于二氧化硅含量超过50%，烧结材料的表面带负电荷。铬（III）和汞（II）在烧结材料上的吸附表明，吸附取决于体系的pH值。在平衡pH值为4.6时，吸附密度为1.40毫克铬/克，在平衡pH值为6.0时，吸附密度为0.43毫克汞/克。背景电解质不影响铬（III）的吸附，但对汞（II）的吸附有显著影响。铬（III）对表面反应位点的亲和力似乎超过汞（II）。进行了竞争吸附实验，以确定铬（III）和汞（II）之间竞争相互作用导致的吸附变化幅度。实验结果表明，较高的竞争溶质浓度会对汞（II）产生更显著的竞争效应。
