Iron-catalyzed coal liquefaction: evidence for isothermal multiplicity

Technical Report · Fri Feb 28 23:00:00 EST 1986

OSTI ID:6276308

Klunder, E B; Krastman, D; Mima, J A

Liquefaction tests in a 1000 lb (coal) per day PDU showed improved distillate yield and decreased hydrocarbon gas yield with recycle of a bottoms stream containing large amounts of pyrrhotite. Efficiencies of hydrogen utilization as high as 11 kg distillate/kg consumed H/sub 2/ were observed for Blacksville No. 2 coal. Similar results were also obtained by addition of pyrite to the feed slurry. The pattern of measured distillate yields is suggestive of multiple steady states in the isothermal reaction system of the PDU. The pattern is explained by postulating an autocatalytic reaction pathway involving hydrogen donors as reactants, in competition with a regressive thermal reaction. The proposed autocatalytic reaction consumes donors by hydrogen transfer to the dissolved coal, but the same reaction also forms additional donor precursors from the coal substrate. Active donors are regenerated in a parallel hydrogenation step that is catalyzed by the pyrrhotite in the system. Results suggest that operating history, as well as operating conditions, determines whether the autocatalytic or the thermal reaction pathway dominates the yield structure. The mechanism is consistent with nonlinear yield responses known to occur in coal liquefaction during bottoms recycle, catalyst addition, and coal blending. 79 refs., 58 figs., 12 tabs.

• Research Organization: USDOE Pittsburgh Energy Technology Center, PA
• OSTI ID: 6276308
• Report Number(s): DOE/PETC/TR-86/4; ON: DE86007752
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010405* -- Coal
Lignite
& Peat-- Hydrogenation & Liquefaction
010600 -- Coal
Lignite
& Peat-- Properties & Composition
BOILING POINTS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHROMATOGRAPHY
COAL LIQUEFACTION
COAL LIQUIDS
CONSUMPTION RATES
DATA
DISTILLATES
ELEMENTS
EXPERIMENTAL DATA
FLUIDS
FUNCTIONAL MODELS
GAS CHROMATOGRAPHY
HIGH PRESSURE
HIGH TEMPERATURE
HYDROCARBONS
HYDROGEN
HYDROGEN TRANSFER
INFORMATION
IRON COMPOUNDS
IRON SULFIDES
LIQUEFACTION
LIQUIDS
MATERIAL BALANCE
MINERALS
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
PROCESS DEVELOPMENT UNITS
PYRITE
PYRRHOTITE
SEPARATION PROCESSES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
YIELDS