摘   要 目前生物炭对土壤重金属的吸附，有良好的应用前景，施用生物炭，能使土壤重金属的生物有效性降低，使其能被稳定固定在土壤中，也能减少农作物对重金属的吸收，防止进入食物链，对人类健康产生危害[1]。为探究生物炭对土壤重金属Cu的钝化与吸附效果，本实验将以竹材加工热解制作的生物炭施用到模拟的二级和三级污染土壤中，分别在60天与150天后，用BCR顺序提取法探究了铜的形态存在形式的转变，并考察了土壤中生物炭的吸附能力变化。实验结果表明，无论是在模拟的二级污染土壤中还是在模拟的三级污染土壤中，150天比60天生物炭吸附Cu的效果更差。生物炭添加在土壤样品中60天或150天后，二级动力学吸附方程比一级动力学吸附方程更能描述生物炭对Cu2+的吸附性能。在生物炭添加于土壤中60天后，Langmuir等温吸附方程比Freundlich等温吸附方程更能准确描述生物炭对Cu2+的吸附性能；而在生物炭添加于土壤中150天后，Freundlich等温吸附方程比Langmuir等温吸附方程更能准确描述生物炭对Cu2+的吸附性能。这项研究可以为土壤的重金属污染治理方面提供一定的理论基础。90297

At present, applications of biochar on soil heavy metal adsorption has a good application prospect, which could decrease the bioavailability of heavy metals in the soil, reduce the heavy metals absorption in crops, and prevent entering the food chain。 In order to explore the effect of biochar on Cu passivation and adsorption in the soil, this study applied bamboo biochar into simulant grade II and grade III polluted soils, analyzed Cu fraction with BCR sequential extraction method, and observed the adsorption abilities of biochar in soils after 60 and 150 days, respectively。 The experimental results show that adding 1% biochar can significantly reduce the content of oxidized Cu in soil。 The Cu adsorption ability of biochar was observed better in 60-day experiment in both of simulant grade II and grade III polluted soils than 150-day。 The total amount of soil Cu could be reduced after additions of biochar。 Adsorption of copper ion biochar accords with the two level dynamic model。 The reaction after 15 hours can reach equilibrium, and adsorption capacity reached the maximum value。 This study can provide a better theoretical basis for the treatment of heavy metal pollution in soil using biochar。 Carbon is added in soil after 60 days, the Langmuir isotherm equation can more accurately describe the adsorption properties of biochar on Cu2+ than Freundlich isotherm。 However, after 150 days, the Freundlich isotherm equation is much better to describe the adsorption properties on Cu2+ in soil。 This study it can provide a theoretical basis for the remediation of heavy metal contaminated soil。

毕业论文关键词：土壤；生物炭；老化；铜；吸附；重金属形态

  Key words: soil; biochar; aging; copper; adsorption; heavy metal speciation

目录

1．引言 4

2材料与方法： 5

2。1供试材料 5

2。2模拟实验方案 5

2。3分析项目及方法 6

2。4数据处理 7

3结果与讨论 7

3。1生物炭添加到土壤样品60天后对Cu全量和形态变化的影响 7

3。1。1生物炭添加到二级污染土壤中60天后Cu全量和形态的变化 7

3。1。2生物炭添加到三级污染土壤中60天后Cu全量和形态的变化