Coal liquefaction with synthesis gas

Technical Report · Sat Sep 01 04:00:00 EDT 1979

OSTI ID:5956435

Appell, H R; Miller, R D; Illig, E G; Moroni, E C; Steffgen, F W

Hydroliquefaction is a well-known technique for coal liquefaction. Work with carbon monoxide, however, showed unexpectedly high liquefaction activity and indicated that the presence of both hydrogen and carbon monoxide (as in synthesis gas) could lead to improved liquefaction, particularly for low rank coals. The objective of the work reported here was to develop a better understanding of the chemistry of liquefying coal with synthesis gas plus water and to assess the potential of such a process. The effects of changing gas composition, temperature, pressure, solvents, catalysts and coal types were studied to better understand the process fundamentals and to lay the groundwork for studies in continuous reactors on a larger scale. A variety of coals were converted in batch autoclaves to a low-sulfur fuel oil at temperature of 425 to 450/sup 0/ C and pressures of 2200 to 2400 psig, using 1:1 (H/sub 2/:CO) synthesis gas at reaction times of 30 to 60 minutes at temperature. Although early work suggested that lignites could be readily liquefied without added catalytic agents, later experiments showed that a greatly improved product could be obtained by adding pyrite, which is normally present only in small amounts. Pyrite or, in particular, its reduction product pyrrhotite, appear to be important catalysts for coal liquefaction, and, in general, the reactivity of coals correlates well with the pyrite (or iron plus sulfur) content. An important consideration is the optimum temperature for reacting carbon monoxide or its (catalytic) intermediates with coal. This temperature is below 400/sup 0/C, and it is necessary to allow for some reaction time between 380 and 400/sup 0/C. Finally, coal liquefaction with synthesis gas appears to be compatible with the type of processing used to produce Solvent Refined Coal or SRC-II.

• Research Organization: Department of Energy, Pittsburgh, PA (USA). Pittsburgh Energy Technology Center
• OSTI ID: 5956435
• Report Number(s): PETC/TR-79/1
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010405* -- Coal
Lignite
& Peat-- Hydrogenation & Liquefaction
BROWN COAL
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CARBONACEOUS MATERIALS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMISTRY
COAL
COAL LIQUEFACTION
COAL RANK
CRYOGENIC FLUIDS
ELEMENTS
ENERGY SOURCES
FLUIDS
FOSSIL FUELS
FUELS
GASES
HYDROGEN
HYDROGEN COMPOUNDS
IRON COMPOUNDS
IRON SULFIDES
KINETICS
LIGNITE
LIQUEFACTION
MINERALS
NONMETALS
ORES
OXIDES
OXYGEN COMPOUNDS
PYRITE
PYRITES
PYRRHOTITE
REACTION KINETICS
SRC PROCESS
SULFIDES
SULFUR COMPOUNDS
SULFUR ORES
SYNTHESIS GAS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
WATER