摘要
以农林废弃物——烟杆的炭化料为原料,采用微波加热氢氧化钾活化法制备了高比表面积活性炭。研究了微波加热时间和碱炭比对活性炭的得率和吸附性能的影响,得到了优化工艺条件,即当微波功率为700 W,加热时间为30min,碱炭比为4∶1,所制备的活性炭碘吸附值为2 239.1 mg/g,亚甲基蓝吸附值为652.5 mg/g,得率为25.48%,产品的吸附性能超过了双电层电容器专用活性炭(LY/T 1617-2004)标准的要求,同常规加热相比,加热时间缩短了87.5%。同时测定了优化工艺条件下制备活性炭的氮气吸附等温线,通过BET法计算了活性炭的比表面积,并通过非定域化密度函数理论表征了活性炭的孔结构。该高比表面积活性炭微、中孔发达,比表面积可达3 406 m2/g,总孔体积为2.157mL/g。
A series of high specific surface area activated carbous were prepared with char of the agricultural and forest waste-tobacco stems as raw materials and KOH as activating agent using a microwave heating procedure. The effects of KOH/C ratio and microwave heating time on the yield and adsorption properties of activated carbon were systematically studied. The optimum rendition has been obtained as KOH/C ratio is 4：1 while microwave power is 700 W with heating time is 30 rain. Thus the experimental results have shown that the field of the activated carbon was 25.48% when the methylene blue adsorption reached 652.5 mg/g and iodine value was 2 239.1 mg/g. The adsorption properties exceeded that of the standard of activated carbon for electric double-layer capadtor. The heating time of microwave heating was shortened 87.5 % mmpaning with that of the conventional process. Furthermore, the activated carbon manufactured under optimum condition was tested by nitrogen adsorption at 77 K. The specific surface area of activated carbon is calculated by BET meethod. The porous structures of the activated carbon were investigated by Non Local Density Function Theory （NLDFT）. The results showed that the obtained activated carbon consisted of abundant micropores and meswores with specific surface area of 3406 m^2/g, total pore volume of 2.157 mL/g.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2008年第12期76-79,共4页
Journal of Wuhan University of Technology
基金
国家自然科学基金(20167001)
关键词
微波加热
氢氧化钾
高比表面积活性炭
孔结构
microwave heating
KOH
high specific surface area activated carbon
pore structure
