硅锰复合物的水热合成及对水中Cu^(2+)的吸附

Hydrothermal synthesis of silico-manganese composite for Cu^(2+) adsorption from aqueous solutions

为了提高吸附剂在低p H条件下去除水中重金属离子的效率,通过水热法合成了一种硅锰复合材料。利用N2-吸附脱附、透射电子显微镜(TEM)以及X射线衍射(XRD)技术对制备的材料进行了表征;并将其用于吸附水中的Cu^(2+),研究了Si O2掺杂量、溶液p H值、初始Cu^(2+)浓度以及吸附时间对吸附效果的影响。结果表明:与纯δ-Mn O2相比,当Si O2含量为7.5%~15%,硅锰复合物对Cu^(2+)的吸附量受溶液p H影响较小,在溶液p H=2~4范围内有更高的Cu^(2+)吸附量;等温吸附曲线符合Langmuir等温吸附模型,计算饱和吸附量为84.68~71.12 mg,与实验值十分接近。

A silico-manganese composite（ SMC） material was synthesized by hydrothermal method in order to improve the efficiency of the adsorbent used for removal of heavy metal ions from aqueous solutions with a lower p H value. The as-prepared materials were characterized by N2adsorption-desorption,transmission electron microscopy and X-ray diffraction techniques. The adsorption of aqueous Cu^2＋onto a variety of SMCs was investigated as a function of the Si O2 content,p H value of working solution,initial concentration of Cu^2＋and adsorption time. The results showed that the p H dependency for adsorption of Cu^2＋on SMCs was lower compared to that on pure δ-Mn O2. As a result,higher adsorption capacities of SMC（ 7. 5% to 15% of silica doping amount） for Cu^2＋could be observed at a lower solution p H（ 2 to 4）. The Langmuir model was employed to describe the adsorption behavior of Cu^2＋onto SMC,and the calculated saturation adsorption capacity of SMC was very close to the experimental value.