Reaction control and gas-liquid mass transfer in free-radical reaction systems and innovative methods of solvent handling and recycling

Slurry phase catalyzed reactions are an important class of reactions employed in the chemical and biochemical industries. Catalytic hydrogenation, oxidation, halogenation and polymerization reactions are a few examples where slurry phase reactions are employed. The liquefaction of coal is another one of the most important slurry-phase reactions. The selectivity and activity of the catalyst in these reactions is observed to be low. This is hypothesized to be the result of poor mass transfer of reactant gas to the liquid phase in most of the cases.; The limitation of poor selectivity can be overcome if the mass transfer rate matches the free radical propagation. This is however, not practical at the present time. The approach used in this study was to use a jet loop type reactor system to control free radical generation rate. A jet loop reactor system was developed as part of the study. The reactor system was evaluated using model reactions such as naphthalene hydrogenation and tetralin oxidation. The reactor system performed better than conventional reactors and required significantly lower amounts of catalyst and resulted in higher selectivity.; A unique gas-driven pumping system was developed and integrated to the reactor system for use under severe coal liquefaction conditions. The integrated coal liquefaction reactor system was used in an initial study to coprocess coal with waste oil. The study indicated the beneficial effects of coprocessing coal with waste materials and indicated that the reactor system was performing better than conventional reactors such as tubing bomb reactors employed for coal liquefaction.; In the second part of this study, filtration was used as an alternative technique to reclaim solvents used by Department of Defense installations. A filtration system was designed and used in a field study to reclaim solvents at Robins Air Force Base in Georgia. The results indicated a significant improvement in the properties of the reclaimed solvents. A solvent recycling program can be implemented using filtration with minimum capital outlays. Solvent handling can be made more versatile by using filtration in combination with distillation.