Patent · US Expired

Multi-stage coal liquefaction and fractionation method

US4664788A · kind A · utility

5Cited by
12References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1985
Grant dateMay 12, 1987
Priority date
Expiry dateSep 19, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S208/952
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A multi-stage coal liquefaction method in which coal is slurried with a primary light solvent, such as toluene, hexane and/or cyclohexane, and a process-derived primary heavy solvent. The coal-primary solvent slurry is treated under coal-liquefying conditions to form a first feed solution containing coal liquefaction products. The first feed solution is treated by a multi-stage supercritical solvent extraction procedure. The final heavy phase produced by this procedure is mixed with a secondary solvent, such as pentane, to produce a second feed mixture, which is treated in a second multi-stage supercritical solvent extraction procedure. Heavy phases recovered from the separate stages of both solvent extraction procedures are blended to provide a recycled primary heavy solvent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.