Regeneration of spent ZnCl/sub 2/ product catalyst from hydrocracking subbituminous coal

Conference · Mon Jan 01 04:00:00 EST 1979 · Am. Chem. Soc., Div. Fuel Chem., Prepr.; (United States)

OSTI ID:5291692

Zielke, C W; Rosenhoover, W A; Struck, R T

It has been demonstrated in batch and continuous bench-scale units that molten zinc chloride is a superior catalyst for liquefaction of coal, coal extract or other heavy hydrocarbons. High quality gasoline of 90 to 92 Research Octane Number is produced in high yield in a single hydrocracking step. Large amounts of zinc chloride are used as the catalyst for high activity, i.e., usually 1 gm of ZnCl/sub 2/ per gm of coal or extract feed. From 1 to 2 parts by weight of product catalyst is generated during the hydrocracking process depending on the ZnCl/sub 2//feed ratio. This product catalyst is contaminated with zinc sulfide, ammonia or ammonium chloride complexed with zinc chloride (formed by the catalyst partially reacting with the sulfur and nitrogen in the feed during the hydrocracking step), carbonaceous residue that cannot be distilled out of the melt, and coal ash, when coal is the feed to the hydrocracking process. To keep the catalyst active, these impurities must be removed in a regeneration process in which the catalyst is converted back to essentially pure zinc chloride. The regeneration is accomplished by burning out the impurities in a combustor containing a fluidized bed of inert silica sand. Hydrogen chloride gas is added to the feed air to convert ZnO to ZnCl/sub 2/ and to prevent formation of ZnO by hydrolysis of zinc chloride in the combustor. Continuous regeneration of this coal-ash-contaminated spent melt from direct hydrocracking of coal and efficient zinc recovery therefrom has now been demonstrated for the first time. In this work zinc recovery was enhanced by introducing a secondary zinc recovery step in which zinc, retained in the coal ash rejected in the primary regeneration step, is largely recovered. This paper presents some of the results of this regeneration work with natural spent melt from direct coal hydrocracking.

• Research Organization: Conoco Coal Development Co., Library, PA
• OSTI ID: 5291692
• Report Number(s): CONF-790917-P3
• Conference Information: Journal Name: Am. Chem. Soc., Div. Fuel Chem., Prepr.; (United States) Journal Volume: 24:3
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010405* -- Coal
Lignite
& Peat-- Hydrogenation & Liquefaction
CARBONACEOUS MATERIALS
CATALYSTS
CATALYTIC EFFECTS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
COAL
COAL LIQUEFACTION
CRACKING
DECOMPOSITION
ENERGY SOURCES
FOSSIL FUELS
FUELS
HALIDES
HALOGEN COMPOUNDS
HYDROCRACKING
LIQUEFACTION
MOLTEN SALTS
PYROLYSIS
REGENERATION
SALTS
SUBBITUMINOUS COAL
THERMOCHEMICAL PROCESSES
ZINC CHLORIDES
ZINC COMPOUNDS
ZINC HALIDES