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SECONDARY REFINING OF COAL DERIVED DISTILLATES AND STUDIES OF COAL LIQUEFACTION POTENTIAL

Objective

THE AIM OF THIS PROJECT IS TWOFOLD,FIRSTLY TO DEVELOP IMPROVED CATALYSTS FOR THE UPGRADING OF COAL DERIVED DISTILLATES AND SECONDLY TO DEVELOP A PROCEDURE FOR THE ASSESSMENT OF THE LIQUEFACTION POTENTIAL OF COALS.
The effect of nitrogen containing and oxygen containing compounds on the hydrogenation of middle distillates from hydrocracking of coal extract liquids has been investigated. Results have been obtained for the hydrogenation of tetralin to decalin over a commercial nickel molybdenum catalyst. The presence of low concentrations of quinoline causes a large decrease in hydrogenation activity while dibenzofuran has only a relatively minor effect. Preliminary results indicate that there is negligibleinteraction between these deactivation processes.
The design of a novel swept bed coal liquefaction reactor is also described. This uses a flow of solvent (tetralin) to remove products rapidly from the heated reaction zone. Preliminary data is available to show the performance of the computer controlled heating system and a first trial with a coal sample has been conducted.
COAL DERIVED DISTILLATES CONTAIN MORE SULPHUR NITROGEN AND OXYGEN IMPURITIES THAN DO EQUIVALENT FRACTIONS DERIVED FROM PETROLEUM.DUE TO THE COMPETITIVE NATURE OF HYDROGENATION,HDS,HDN AND HDO REACTIONS UPGRADING OF COALS DISTILLATES ON CONVENTIONAL CATALYSTS PROCEEDS AT AN UNACCEPTABLY SLOW RATE.A TWO YEAR PROGRAMME OF WORK IS PROPOSED TO DEVELOP NEW CATALYSTS TAILOR-MADE TO COAL LIQUIDS PROCESSING.
THE WORK WILL CONCENTRATE ON CATALYSTS OF THE NI-MO AND COMO TYPE (POSSIBLY PROMOTED BY P) AND WILL INCLUDE SOME EXPLORATORY WORK ON OTHER GROUP VIII METAL SULPHIDES.FORMULATIONS HAVING BEEN SCREENED FOR HDS AND HYDROGENATION ACTIVITY IN MICROREACTOR TESTS WILL BE EXAMINED UNDER A RANGE OF APPROPRIATE REACTION CONDITIONS IN A HIGH PRESSURE TRICKLE-BED REACTOR AND HIGH PRESSURE AUTOCLAVE.SYSTEMATIC TESTS WILL FIRST BE PERFORMED ON MIXTURES OF MODEL COMPOUNDS TO STUDY REACTION PATHS AND RELATIVE REACTION RATES USING SUPPORTED CATALYSTS.THE SAME CATALYSTS WILL BE FURTHER TESTED ON COAL DERIVED DISTILLATES.FURTHER TESTS USING MODEL COMPOUNDS AND UNSUPPORTED CATALYSTS WILL INVESTIGATE THE EFFECT OF CATALYST FORM.

IN PARALLEL TO THE DEVELOPMENT OF CATALYSTS THERE BE AN ATTEMPT TO DEVELOP A NEW METHOD FOR MEASURING THE LIQUEFACTION POTENTIAL OF COAL.LIQUEFACTION PERFORMANCE WILL BE RELATED TO THE HEATING RATE OF THE COAL AND TO THE RESIDENCE TIME OF LIQUID PRODUCTS IN THE REACTOR.

STATE OF ADVANCEMENT:
THE FIRST PERIOD REPORT IS EXPECTED IN JANUARY 1988.

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY AND MEDICINE
Address
South Kensington Campus
London
United Kingdom