生物氧化锰与砷的交互作用及其影响因素
文献类型：学位论文
| 作者 | 王冰清 |
| 学位类别 | 硕士 |
| 答辩日期 | 2014-05 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 郑袁明 |
| 关键词 | 生物氧化锰 砷 锰氧化细菌 化学氧化锰 氧化 吸附 biogenic manganese oxide arsenic Mn-oxidizing bacteria chemical manganese oxide oxidation adsorption |
| 其他题名 | Interaction of Arsenic with Biogenic manganese oxides and its critical influencing factors |
| 学位专业 | 生物工程 |
| 中文摘要 | 锰氧化物在自然界中广泛存在，能够与多种重金属元素发生吸附、氧化反应。As 是一种毒性较强的重金属元素，氧化锰能够将毒性较强的As(III)氧化为毒性较弱的As(V)，并将其吸附固定，从而达到去除砷的目的，具有良好的环境修复应用前景。本文研究了从土壤中分离得到的四株锰氧化菌在不同pH、Mn(II)浓度下的锰氧化活性，并利用GY16 形成 的生物氧化锰(以化学氧化锰水羟锰矿为对照)，分析了锰氧化物与砷的交互作用，以及生物氧化锰对溶液中砷的去除能力，以期为生物氧化锰应用于砷污染环境修复提供科学依据，具体研究结果如下： 1. 利用平板稀释法从土壤中分离得到WHS26、GY16、LZ2、LZ4 等具有较强锰氧化活性的菌株。pH 为7-8 时这些菌株具有最高的锰氧化活性。但不同菌株的最适pH 有所不同。同时，在最佳pH 下，WHS26、LZ2、LZ4 在Mn(II)浓度为10mM 时，具有最佳锰氧化效率，而GY16 在Mn(II)浓度为20mM 时，锰氧化量最大。 2. 通过生物氧化锰与化学氧化锰的对比研究发现，由GY16 形成的生物氧化锰对As的氧化吸附量（换算为单位摩尔数氧化锰的吸附量）明显高于化学氧化锰水钠锰矿；而水钠锰矿对As(III)的氧化速率则要明显高于生物氧化锰。随着pH 的升高，生物氧化锰对As(III)/As(V)的氧化/吸附量均逐渐降低，而水钠锰矿对As(V)的吸附量逐渐增加。 3. 研究多种离子下锰氧化物与砷的反应，结果显示：当反应体系中有阳离子存在时，生物氧化锰对As(III)的氧化量降低，对As(V)的吸附量有所增加。此外，在含有H2PO4-的体系中，随着时间的推移，As(V)逐渐从生物氧化锰表面解吸。 4. 生物氧化锰对模拟土壤溶液中As 的去除能力要低于其对水溶液中As 的去除能力,这主要是由于土壤环境中具有更为复杂的离子环境。 5. 与新生成的生物氧化锰相比，钝化的生物氧化锰对As 的氧化吸附能力较低，且随着钝化时间的增加，其对As 的氧化吸附能力逐渐减弱。 |
| 英文摘要 | Manganese-oxides, abundant in environment, can oxidize and adsorb heavy metals. Arsenic is a typical toxic heavy metal and can interact with manganese-oxides. For example, arsenite can be oxidized to less toxic arsenate by manganese-oxides, which can decrease arsenate mobility by increasing its tendency to be adsorbed. Owing to the high reactivity of Mn-oxides, their application to the biological remediation of arsenic has attracted a great deal of attention. In this study, four Mn-oxidizing bacteria were isolated from Fe-Mn nodules or Chinese soils. The effects of pH and Mn(II) concentration on Mn(II) oxidation were investigated. Furthermore, the interactions of manganese oxides (biogenic Mn oxides formed by GY16 and birnessite) with arsenic in distilled water and soil solution were studied. 1. Four Mn-oxidizing bacteria (WHS26、GY16、LZ2、LZ4) presented the highest oxidation ability when pH was adjusted to 7-8 and Mn(II) concentration was 10-20mM. 2. The oxidation and adsorption capacities of biogenic Mn oxides for arsenic were greater than those of birnessite. As(III) oxidation by biogenic manganese oxide was initially rapid but slowed appreciably after several hours reaction. The oxidation and adsorption capacities of biogenic manganese oxide decreased with the increase of pH. However, the amount of As(V) adsorbed by birnessite increased with the increase of pH. 3. Zn(II)/Mn(II)/Co(II) could inhibit As(III) oxidation and promote As(V) adsorption by biogenic manganese oxide. H2PO4- could desorb As(V) from biogenic manganese oxide. 4. The amount of As(III) oxidized and As(V) adsorbed by biogenic manganese oxide in soil solution was much less than that in distilled water； 5. When biogenic manganese oxide was passivated, vacancy sites were occupied mostly and the oxidation and adsorption capacities of Mn-oxides decreased greatly. The obtained results in this study will provide a fundamental technical support for biogenic manganese oxide application in environmental remediation of arsenic contamination. |
| 公开日期 | 2015-06-12 |
| 源URL | [http://ir.rcees.ac.cn/handle/311016/13460]  |
| 专题 | 生态环境研究中心_土壤环境科学实验室 |
| 推荐引用方式 GB/T 7714 | 王冰清. 生物氧化锰与砷的交互作用及其影响因素[D]. 北京. 中国科学院研究生院. 2014. |
入库方式： OAI收割
来源：生态环境研究中心
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。