CHEMTECH, Jan 1993 v23 n1 p22(3) 
                Another use for old tires: coprocess them with coal to make 
                liquid fuels. Malvina Farcasiu. 
            Abstract: Used rubber tires were coprocessed with bituminous coal to 
            yield a liquid fuel that containes more than 80% heptane-soluble, 
            hydrogen-rich fraction. The process was based on the assumption that 
            the organic materials and the carbon black in the rubber tireswill 
            function as liquefaction solvents and as catalyst to reactions 
            involved incoal liquefaction, respectively. Coprocessing can proceed 
            with varying rubber to coal ratios, ensuring a steady-state 
            operation. Unreacted coal and tires mayalso be used as alternative 
            energy sources in the plant. 
             
             Article A14051700