离石黄土对Cr^(3+)的去除及对Cr^(3+)形态分布的影响  

Removal of Chromium(Ⅲ) and Effect of Speciation Distribution of Chromium(Ⅲ)by Lishi Loess

作　　者：黄征[1] 马腾[2] 罗维[1] 徐齐福[3] 雷荣 万燎榕[5] 

机构地区：[1]中国地质大学研究生院,武汉430074 [2]中国地质大学环境学院 [3]中国交通部第二公路勘察设计研究院,武汉430052 [4]中国第一冶金建设公司基础公司,武汉430081 [5]江西省水利规划设计院,南昌330000

出　　处：《地质科技情报》2006年第3期93-96,共4页Geological Science and Technology Information

基　　金：国家自然科学基金资助项目"铬同位素测试技术及其在地下水污染修复中的应用"(40402021);中国地质大学(武汉)优秀青年教师资助计划"黄土对重金属及石油类污染物吸附实验研究"(CUGQNL0303);教育部科学技术研究重点项目"惰性气体同位素在地下水流动模式识别中的应用"(104038)

摘　　要：选取离石黄土中的黄土及黏土层和重金属铬作为研究对象,通过等温吸附实验及Tessier法形态提取实验,分析了Cr3+在离石黄土中的存在形态,并对其分布规律进行了比较,研究了离石黄土对Cr3+的去除机理。实验结果表明:黄土及黏土层对Cr5+均有很好的去除效果,吸附率超过98%。当初始质量浓度ρ0<100 mg/L时,其等温吸附曲线属Henry型。形态提取研究发现:黄土及黏土层对Cr3+的吸附形态以碳酸盐结合态和铁锰氧化物结合态为主,两者的总和都在95%以上,有机质结合态较少且相对稳定。受黄土及黏土层化学成分差异的影响,它们对Cr3+的去除在形态分布上存在一定差异,黄土中Cr3+的形态分布:碳酸盐结合态>铁锰氧化物结合态>有机质结合态>可溶态>可交换态;黏土层中Cr3+的形态分布:铁锰氧化物结合态>碳酸盐结合态>有机质结合态>可溶态>可交换态。To study the removal mechanism of chromium（Ⅲ） by Lishi loess,the loess and clay layer inside the Lishi loess was taken as an equivalent in the comparative research. The speciation distribution of chromium in Lishi loess was analyzed and compared through a series of experiments on isothermal sorption and sequential chemical extraction. It was found that both loess and clay layer have great removal capacity for chromium（Ⅲ） and the removal proportion with various initial Cr（Ⅲ） concentrations up to 98% or more. The isotherms absorption curves might accord with Henry type when the initial concentration of chromium （Ⅲ） was under 100 mg/L. The results of chemical extraction showed that the predominant chromium species sorbed on both the loess and clay layer were the chromium（ Ⅲ ） bound to carbonate, iron and manganese oxides,the total content of these two kinds of species was up to 95% ,while the content of chromium （ Ⅲ ） bound to organic matter was less but relatively invariable. Due to the chemical components differences between them, there are some differences in the speciation distribution of chromium（ Ⅲ） presented in them.

关 键 词：黄土 黏土层 CR^3+ 形态 

分 类 号：X142[环境科学与工程—环境科学]