N_2高温热处理对活性炭孔道结构及表面化学性质的影响

The effect of high temperature treatment in nitrogen on the pore channel structure and the surface chemical properties of activated carbon

在氮气气氛下对活性炭进行1000℃高温热处理，研究了高温处理前后活性炭微观结构和表面化学性质的变化。低温（77K）N2吸附结果表明，经高温处理后活性炭比表面积和孔容增加，增长率分别达59．2％和83．3％。通过密度函数理论解析热处理前后活性炭的孔径分布得出，高温热处理后活性炭2-4nm的孔体积明显增加。Boehm滴定和红外光谱分析结果表明，对活性炭进行高温热处理会使活性炭表面不饱和键断裂，含氧酸基团热解，降低活性炭表面酸性基团数量。

By modifying the activated carbon in nitrogen atmosphere at 1 000 ℃ high temperature, the change of pore channel structure and surface chemical properties of activated carbon were studied. Compared to the result of N2 absorption at low temperature （77 K）, the specific surface area and pore volume of activated carbon after high temperature treatment were obviously enhanced, which growth rate equals to 59.2% and 83.3%,respectively. The pore distribution of activated carbon was analyzed using the density functional theory before and after modification, it demonstrated that the pore volume of the activated carbon within 2-4 nm increased obviously after high temperature modification. At last, the Boehm titration and infrared spectroscopy result indicated that the unsaturated bonds on the surface of the activated carbon were broken down and oxyacid groups dissociated after the high temperature treatment, leading to the decrease of the number of acidic ~rouos.