Catalytic activity of fullerenes for hydrocracking coal extracts

A liquefaction extract of Point of Ayr coal (UK) was hydrocracked using a mixture of fullerenes as dispersed catalyst and tetralin as solvent. Structural characteristics of the hydrocracking products were examined as a function of increasing reaction time and compared with those of products prepared in the absence of catalyst. Comparison of t.g.a.-derived boiling point distributions showed that the proportion of material boiling at temperatures below 450°C progressively increased with reaction time up to 120 min. Size exclusion chromatograms (s.e.c.) of products indicated a similar steady reduction in the proportion of material observed at the exclusion limit of the column, at up to 90 min reaction. However, reaction between 90 and 120 min appeared to have the reverse effect. Comparison with hydrocracking in the absence of catalyst gave no indication that the fullerenes enhance reductions in boiling point distributions or in apparent molecular masses. MALDI-m.s. largely confirmed findings by s.e.c. The evidence strongly suggests that fullerenes used in these experiments were unable to retain their integrity during the process.