Free radicals in coal and coal conversions. 9. Statistical correlative models of the effect of process variables on hydroliquefaction products

Abstract Previous papers in this series have reported the degree of coal conversion in autoclave and e.s.r. cavity liquefaction experiments and free radical measurements from the e.s.r. liquefaction experiments. Here a correlative model for the liquefaction products is discussed in terms of temperature,solvent reactor type, pressure and other process variables, similar in form to that used for the free-radical concentration measurements in an earlier paper in this series. Solvent-time interactions were found to be the most significant term in modelling the yields. Based on the strong similarity in the functional form of the radical and product yield models, a model of conversion and the various yields as a fraction of radical concentration and other process variables was constructed. Free-radical concentration and its interaction with solvent were found to be very significant.