巯基化、钠化和酸化膨润土对Cu2+，Pb2+和Zn2+的吸附性能研究

基于改性膨润土可能存在的优异吸附能力，利用傅里叶变换红外光谱仪和场发射扫描电镜研究分析了巯基化、钠化及酸化三种改性膨润土对Cu2+，Pb2+和Zn2+的等温吸附与竞争吸附实验结果。研究结果表明，在单一重金属离子的等温吸附环境下，巯基化膨润土对Cu2+，Pb2+和Zn2+的吸附能力明显优于其他两种材料，且对Pb2+具有一定的吸附选择性，吸附率达到近100%；在竞争吸附环境下，三种改性膨润土对Cu2+，Pb2+和Zn2+的吸附率都有所下降，但巯基化膨润土仍旧能够保持较好的吸附能力，较其他膨润土的吸附率大约高出10%～40%；三种重金属离子的吸附量均表现为Cu2+＞Pb2+＞Zn2+，这与三种重金属离子的竞争能力、化学亲和力等大小有关；膨润土的巯基改性，步骤简单且吸附重金属的效果好，对膨润土改性及其应用具有重要意义。

Adsorption Properties of Thiol-Modified,Sodium-Modified and Acidified Bentonite for Cu2+, Pb2+ and Zn2+

In order to investigate the adsorbability of modified bentonite, Fourier Transform Infrared Spectrometer (FTIR Spectrometer) and Scanning Electron Microscope(SEM) were carried outto characterize the properties of samples. The amount of Cu2+, Pb2+ and Zn2+absorbed by three kinds of modified bentonite, thiol-modified bentonite, sodium-modified bentonite and acidified bentonite, in the environment of isothermal adsorption and competitive adsorption, were investigated and analyzed respectively. The results show that in the environment of isothermal adsorption, the adsorption capacity of thiol-modified bentonite is much superior to others, especially appearing adsorptive selectivity for Pb2+, the adsorption rate amounts to nearly 100%. In the environment of competitive adsorption, the adsorption rate for three kinds of modified bentonite on Cu2+, Pb2+and Zn2+ all decrease to some extent, but thiol-modified bentonite performs better in generally, which shows 10%～40% higher than the others, besides, the competitive adsorption ability of three metal ions can be given as Cu2+>Pb2+>Zn2+, which relate to their competitive ability, chemical affinity and so on. The modified process of thiol-modified bentonite is simple and the effect on adsorbing heavy metals is desirable. Therefore, it is an important study of modified bentonite and its application.