松子壳热解炭活化特性研究

Study on activation properties of pine nut shell pyrolytic carbon

以松子壳为原料,采用常规热解法得到松子壳炭,利用水蒸气活化的方法制备了微孔率较高的活性炭,并测定其吸附能力。利用红外光谱(FT-IR)、氮气吸脱附曲线、扫描电镜(SEM)对热解炭及相应活性炭进行了表征。最佳活化工艺为活化温度850℃,活化时间60 min,水蒸气流量0.3 g/min。在该条件下松子壳活性炭得率为34%,亚甲基蓝吸附值为186 mg/g,碘吸附值为1 097 mg/g,比表面积为1 094.895 m2/g,平均孔径为3.95nm。微观结构分析表明,热解炭已经具备一定的孔隙结构,活化过程中活化剂能够有效去除堵塞热解炭孔隙的杂质和不定型炭,形成丰富的微孔结构和少量的介孔、大孔。该研究为松子壳活性炭的制备提供了理论依据。

Activated carbon with a high microporosity was prepared by the method of steam activation with pine nut shell carbon,which was got by the method of conventional pyrolysis with pine nut shell., its adsorption capacity was tested. The pyrolyticcarbonand corresponding activated carbon were characterized by infrared spectrometry, nitrogen adsorption and scanning electron microscopy. The results indicated that optimal conditions for activation were： temperature of 850 ℃, time of 60 min, and steam consumption of 0.3 g/min. The experiments under these optimized conditions found that the yield of activated carbonwas 34%,methylene blue adsorption of activated carbon was 186 mg/g, iodine value was 1 097 mg/g, BET surface area was 1 094.895 m^2/g and average poresize was 3.95 nm. Microstrueture analysis showed that the pyrolytic carbon had already formed certain pore structure. During the activa- tion process, activator could effectively remove the impurities and amorphous-carbon in the pore, and forma large number of micropores, a few mesopores and macropores.. The study provided significant theoretical parameters for the preparation of pine nut shellactivated carbon.