Pyrolysis of a lignite in an entrained flow reactor: 2. Effect of metal cations on decarboxylation and tar yield |
| |
| Affiliation: | 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, 100190, China;2. University of Chinese Academy of Sciences, Beijing, 100049, China;1. Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, China;2. Center of Biomass Engineering/College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China;3. State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China;1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China;2. University of Chinese Academy of Sciences, Beijing 100049, China;1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China;2. University of Chinese Academy of Sciences, Beijing 100049, China;1. Fuels and Energy Technology Institute, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia;2. School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, PR China;3. State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, PR China;1. Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, Russia;2. Bauman Moscow State Technical University, Moscow, Russia |
| |
| Abstract: | The role of exchangeable cations in the release of carboxylic functional groups and tars from a Montana lignite has been studied. Pyrolysis was carried out in an entrained flow reactor using a dilute stream of coal particles, and high heating and cooling rates. Direct determination of the carboxylic functional groups on the coal and char samples by ion exchange with barium acetate was employed to study both the amount and kinetics of decarboxylation. These results indicate that the presence of metal cations decreases the extent of decarboxylation at temperatures of 973, 1073 and 1173 K when compared with the behaviour of an acid washed lignite. It was also possible to determine first order activation energy values using this direct measure of decarboxylation. The activation energies determined for decarboxylation were 100 and 97 kJ mol−1 for the raw and acid washed samples, respectively. Furthermore, it is reported that the presence of metal cations on the coal resulted in a decrease of tar release of 70–94%. Analysis of the tars by Fourier transform infrared spectroscopy indicated that the tars released during pyrolysis were more aliphatic when metal cations were present. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
