Recovery of hard acids and soft bases from decomposed coal
US5489377A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 1994 |
| Grant date | Feb 6, 1996 |
| Priority date | — |
| Expiry date | Aug 12, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G1/086
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An improved process for recovering hard acids and soft bases used to decompose coal in which finely divided coal particles are contacted with a hard acid in the presence of a soft base at temperatures of from 0.degree. to 100.degree. C., said hard acid being characterized by a heat of reaction with dimethylsulfide of from 10 kcal/mol to 30 kcal/mol and said soft base being characterized by a heat of reaction with boron trifluoride of from 10 kcal/mol to 17 kcal/mol, followed by extracting the decomposed coal to remove said hard acid and soft base wherein the improvement comprises performing said extraction at a temperature of about 0.degree. to about 50.degree. C. using dimethylcarbonate as the extraction solvent, and wherein following said dimethylcarbonate extraction, said coal is extracted with water at a temperature of from about 60.degree. to 275.degree. C., and wherein following said water extraction, said coal is soxhlet extracted in sulfolane at a temperature of about 25.degree. to about 350.degree. C., and wherein following said sulfolane extraction, said coal is soxhlet extracted to remove said sulfolane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.