表面功能化活性炭对水溶液中汞离子的吸附

Adsorption of Mercury Ion in Aqueous Solution by Surface Functionalized Activated Carbon

利用硝酸氧化改性和氨还原改性实现活性炭表面功能化,并通过静态吸附实验研究了改性前后活性炭对水溶液中汞离子的吸附性能。硝酸改性使得活性炭表面含氧官能团数量增多,氨改性后成功在活性炭上引入含氮官能团。实验结果表明在pH值为4～7的范围内有较好的吸附效果。吸附等温线和吸附动力学结果表明活性炭表面功能化可以提高对水溶液中汞离子的吸附性能。活性炭表面含氧官能团和含氮官能团与汞离子发生离子交换和配位络合作用。

Activated carbon was modified with HNO3 and NH3 for surface functionalization. Mercury ion adsorption properties by activated carbon before and after modification were studied through batch experiments. It was showed that content of oxygen-containing functional groups on the surface of activated carbon increased after modification with HNO3,and the nitrogen-containing functional groups was introduced onto the surface of activated carbon. Results showed that activated carbon had good adsorption abilities in the pH range of 4 ~ 7. The results of adsorption isotherm and adsorption kinetic indicated that surface functionalized activated carbon showed an increased adsorption capacity in the removal of mercury ion. It was showed that just the oxygen-containing on the surface of HNO3-AC and the nitrogen-containing functional groups on the surface of NH3-AC were complexed with Hg+through ion exchange and formation of coordination complexes.