Detection of low temperature carbon gasification using DSC and TGA

✍ Scribed by I.M.K. Ismail; P.L. Walker Jr.

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 897 KB
• Volume: 27
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(89)90005-5

✦ Synopsis

Abstraet-The intc~~ct~on of 0: with Saran char was followed in the temperature range 77-222°C using differential scanning calorimrtry and thermal gravimetric analysis. At 77°C oxygen chemisorption was accompanied by 0: physical adsorption. At 100°C only oxygen chemisorption was detected, making possible the calculation of enthalpy of chemisorption. At 125°C and above oxygen chemisorption was accompanied by char gasification. It was possible, using some reasonable assumptions, to separate these two processes and obtain rates for each. Rates of char gasification were orders of magnitude higher than predicted by extrapolation of high temperature (450-550°C) Zone I gasification data. It suggests that super active sites exist at low temperatures which are rapidly annealed out at higher temperatures and thus do not take part in char gasification.