CO_2活化制备椰壳基活性炭

以600℃下炭化2h后的椰壳炭化料为原料,通过CO2活化制备椰壳基活性炭,研究了活化温度、活化时间、CO2流量对活性炭得率及其吸附性能的影响。同时测定了该活性炭的N2吸附等温线,通过非定域化密度函数理论表征活性炭孔径分布。在适宜的工艺条件,所制备活性炭的得率为24%,碘吸附值为1428mg/g,其比表面积、总孔容积、微孔容积分别可达:1653m2/g,1.045cm3/g,0.8582cm3/g,且以2nm以下的微孔为主,产品性能达到了双层电容器专用活性炭(LY/T1617—2004)标准。

Preparation of coconut shells-based activated carbons with CO_2 activation

The activated carbons were prepared from carbonized coconut shells at 600 ℃ for 2 hour using CO_2 as the activation agent. The effects of activation temperature, hold time and CO_2 flow-rate on the yield and adsorption property of the activated carbons obtained were systematically studied. The porous size distribution of activated carbon was investigated by Nonlocal Density Function Theory (NLDFT). Furthermore, the activated carbon prepared under optimum condition was tested by nitrogen adsorption at 77 K. The results show that the yield and iodine adsorption value of the activated carbon are 24% and 1 428 mg/g, respectively. The BET surface area, total volume and micropore volume of the activated carbon were 1 653 m~2/g, 1.045 cm~3/g and 0.8582 cm~3/g, respectively, which attains the standard of activated carbon for electric double-layer capacitor.