A new two-step oxidative degradation method for producing valuable chemicals from low rank coals
- Kyoto Univ. (Japan). Dept. of Chemical Engineering
Brown coals are abundant fossil resources, but they have not been utilized to a large extent because of their low calorific values. Considering that brown coals consist of small aromatic ring structures with many functional groups, utilization methods reflecting the structure should be explored. From this viewpoint the authors have presented a new method to produce valuable chemicals from brown coals under mild conditions. Several brown coals were oxidized in 30%-H{sub 2}O{sub 2} aqueous solution at between 40 and 80 C under atmospheric pressure. When North Dakota lignite was oxidized for 24h at 60 C, 60 wt% of the coal decomposed to water soluble organics, 63% of which were, surprisingly, chemicals such as oxalic acid and acetic acid. From the examination of the structure of the water-soluble organics, the authors also presented two methods for upgrading the water-soluble organics. One is the Fenton oxidation of water-soluble organics by which the yield of small molecule components reached more than 60 wt%. The other is the decomposition of water-soluble organics in a sub-critical water by which benzene was produced surprisingly in 12 wt% yield. Thus it was clarified that the proposed methods are effective to produce valuable chemicals from brown coals with low energy supply.
- OSTI ID:
- 349145
- Report Number(s):
- CONF-980985--; ISBN 1-890977-15-2
- Country of Publication:
- United States
- Language:
- English
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