Chiu Chien-Chih, Cheng Chia-Jung, Lin Tzu-Huei, Juang Kai-Wei, Lee Dar-Yuan
Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 106, Taiwan.
J Hazard Mater. 2009 Jan 30;161(2-3):1239-44. doi: 10.1016/j.jhazmat.2008.04.081. Epub 2008 Apr 29.
This paper compared the effectiveness of four organic materials for decreasing the amounts of soil extractable Cr(VI) in Cr(VI)-contaminated soils using the DOWEX M4195 resin-extraction method. Organic matters were added into Cr(VI)-spiked soils [500 mg Cr(VI)(kgsoil)(-1)] in the form of sugarcane dregs compost (SCDC), cattle-dung compost (CDC), soybean meal (SBM) and rice bran (RB), in the amounts of 0, 1%, and 2% by dry weight, respectively. The results indicated that adding only 1% organic matter to the studied soils could effectively decrease the amount of soil resin-extractable Cr(VI) after 12 days of incubation. The decrease of resin-extractable Cr(VI) by organic materials was mainly the result from the reduction of Cr(VI) to Cr(III) supported by the XANES spectroscopy. Among the four tested organic materials, SBM and RB had higher effectiveness in decreasing soil resin-extractable Cr(VI) than CDC and SCDC. This result may be due to the fact that SBM and RB have more dissolved organic carbon (DOC) and protein than CDC and SCDC. Therefore, it was concluded that the contents of DOC and protein are the main factors that determine the effectiveness of organic materials for decreasing the amounts of soil available Cr(VI) in Cr(VI)-contaminated soils.
本文采用DOWEX M4195树脂萃取法，比较了四种有机材料在降低六价铬污染土壤中可提取六价铬含量方面的效果。将有机物质以甘蔗渣堆肥（SCDC）、牛粪堆肥（CDC）、豆粕（SBM）和米糠（RB）的形式分别以干重0%、1%和2%的量添加到添加了六价铬的土壤[500毫克六价铬/（千克土壤）⁻¹]中。结果表明，在研究的土壤中仅添加1%的有机物质，培养12天后就能有效降低土壤树脂可提取六价铬的含量。X射线吸收近边结构光谱表明，有机材料对树脂可提取六价铬的降低主要是由于六价铬还原为三价铬所致。在四种测试的有机材料中，SBM和RB在降低土壤树脂可提取六价铬方面比CDC和SCDC更有效。这一结果可能是因为SBM和RB比CDC和SCDC含有更多的溶解有机碳（DOC）和蛋白质。因此，得出结论，DOC和蛋白质的含量是决定有机材料在降低六价铬污染土壤中有效六价铬含量方面效果的主要因素。
