Zhang Xin-Yan, Wang Qi-Chao, Zhang Shao-Qing, Sun Xiao-Jing, Zhang Zhong-Sheng
Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012, PR China.
J Hazard Mater. 2009 Sep 15;168(2-3):1575-80. doi: 10.1016/j.jhazmat.2009.03.050. Epub 2009 Mar 21.
Stabilization/solidification (S/S) of mercury-containing solid wastes using thiol-functionalized zeolite and cement was investigated in this study. The thiol-functionalized zeolite (TFZ) used in the study was obtained by grafting the thiol group (-SH) to the natural clinoptilolite zeolites, and the mercury adsorption by TFZ was investigated. TFZ was used to stabilize mercury in solid wastes, and then the stabilized wastes were subjected to cement solidification to test the effectiveness of the whole S/S process. The results show that TFZ has a high level of -SH content (0.562 mmol g(-1)) and the adsorption of mercury by TFZ conform to the Freundlich adsorption isotherm. The mercury adsorption capacity is greatly enhanced upon thiol grafting, the maximum of which is increased from 0.041 mmol Hg g(-1) to 0.445 mmol Hg g(-1). TFZ is found to be effective in stabilizing Hg in the waste surrogate. In the stabilization process, the optimum pH for the stabilization reaction is about 5.0. The optimum TFZ dosage is about 5% and the optimum cement dosage is about 100%. Though Cl(-) and PO(4)(3-) have negative effects on mercury adsorption by TFZ, the Portland cement solidification of TFZ stabilized surrogates containing 1000 mg Hg/kg can successfully pass the TCLP leaching test. It can be concluded that the stabilization/solidification process using TFZ and Portland cement is an effective technology to treat and dispose mercury-containing wastes.
本研究考察了使用硫醇官能化沸石和水泥对含汞固体废物进行稳定化/固化（S/S）处理。本研究中使用的硫醇官能化沸石（TFZ）是通过将硫醇基团（-SH）接枝到天然斜发沸石上获得的，并对TFZ对汞的吸附进行了研究。TFZ用于稳定固体废物中的汞，然后对稳定后的废物进行水泥固化，以测试整个S/S过程的有效性。结果表明，TFZ具有较高的-SH含量（0.562 mmol g(-1)），且TFZ对汞的吸附符合Freundlich吸附等温线。硫醇接枝后汞的吸附容量大大提高，最大值从0.041 mmol Hg g(-1) 增加到0.445 mmol Hg g(-1)。发现TFZ对模拟废物中的汞具有稳定作用。在稳定化过程中，稳定化反应的最佳pH约为5.0。TFZ的最佳用量约为5%，水泥的最佳用量约为100%。虽然Cl(-) 和PO(4)(3-) 对TFZ吸附汞有负面影响，但含1000 mg Hg/kg的TFZ稳定化模拟物的波特兰水泥固化能成功通过TCLP浸出试验。可以得出结论，使用TFZ和波特兰水泥的稳定化/固化工艺是一种处理和处置含汞废物的有效技术。
