摘要
用常规分析方法分析了废轮胎热解炭的成分和性质,用X射线能谱分析法、压汞法、N2吸附法等测定了热解炭的孔隙结构特性,并用CO2、含2%氧气的氮气流和水蒸气等活化气体对热解炭进行活化方面的研究。结果表明,热解炭灰分和硫含量比较高;两种不同粒径热解炭的比孔容积均在r≈25nm处有最大值;在相同活化时间和活化剂流速下,温度越高,活化炭烧失率越大,比表面积也越大;在一定温度和活化剂流速下,烧失率和比表面积随着活化时间的增加而增大;对所有试验工况,烧失率越大,活化炭比表面积也越大。总体上水蒸气活化炭与CO2的活化效果较好,而含2%O2的氮气流活化的效果则次之。活化炭与商业活性炭的比较显示,前者具有较发达的孔隙结构,在进行大分子物质吸附时,具有替代商业活性炭的潜力。
The composition and pore-characterization of char from pyrolysis of used tires were determined in this paper. Three oxidizing agents were used for the activation of carbonized char, including steam, CO_2 and 2% O_2 in nitrogen. Char-activation with CO_2 was conducted primarily. The activated char can get a great surface area, which can be used to handle organic elding and textile industry waste. The result shows that the content of ashes and sulfurs in the pyrolysis char is pretty high and there is a maximum pore volume at the pore radius of about 25nm. At the condition of same activation time and gas flow rate, the higher the temperature is, the larger the burn-off rate and the surface area are. Also, at the condition of the same temperature and gas flow rate, the longer activated time is, the larger burn-off rate and BET are. For all activation experiments, the higher burn-off rate would result in larger surface area. The activation effect with steam and CO_2 is better, and followed by that with 2% O_2 in nitrogen. By the comparison of activated char and commercial activated carbon, the former has a profound pore-characterization and it has a potential to substitute commercial activated carbons for the macromolecular absorption.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2004年第3期301-306,共6页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金(50076037)~~
关键词
废轮胎
热解炭
活化炭
比表面积
烧失率
used tires
pyrolysis
pyrolytic char
activated carbon
surface area
burn-off rate
