Mild pyrolysis of selectively oxidized coals. Technical report, September 1--November 30, 1991
- Resource Type
- Technical Report
- Authors
- Source
- Other Information: PBD: [1991]
- Subject
- 01 COAL, LIGNITE, AND PEAT BITUMINOUS COAL
DESULFURIZATION
PYROLYSIS
ORGANIC SULFUR COMPOUNDS
REMOVAL
PROGRESS REPORT
OXIDATION
VOLATILE MATTER
PARTICLE SIZE 010402
PURIFICATION AND UPGRADING
PYROLYSIS AND CARBONIZATION
- Language
- English
The primary objective of this study is to investigate the removal organic sulfur from selectively oxidized Illinois coals using mild thermal/chemical processes. Work completed this quarter includes the investigation of the mild pyrolysis of unoxidized coals plus a selection of selectively oxidized coals. In addition the effect of particle size and extent of oxidation on pyrolysis was investigated. Some preliminary data concerning pyrolysis under vacuum and ambient pressure was also obtained. Work completed this quarter supports the following conclusions: (1) Desulfurization of unoxidized coals increases with increasing pyrolysis temperature and correlates with the loss of volatile matter. (2) Particle size did not influence the extent of desulfurization significantly. (3) Removing pyrite prior to pyrolysis helps to achieve a lower sulfur product beyond that expected from the removal of pyrite alone. (4) The extent of selective oxidation in teh pretreatment step did not effect the level of desulfurization obtained by pyrolysis alone. However this factor was important in the desulfurization obtained with supercritical methanol (SCM)/base. (5) Up to 84% of the sulfur has been removed from the IBC 101 coal by combining selective oxidation and SCM/base reactions. (6) Evidence for regressive reactions between volatilized sulfur compounds and partially desulfurized products was obtained by studying how changes in pyrolysis pressure effected the product sulfur content.