Fuel production by hydrocracking of non-olefinic plastics and vacuum gasoil blends

Abstract

The catalytic hydrocracking of different blends of non-olefinic polymers (polystyrene, polymethylmethacrylate and polyethylene terephthalate) with vacuum gasoil has been studied to produce fuel streams suitable for inclusion in refinery pools. For this purpose, a catalyst synthesized in the laboratory composed of Pt and Pd supported on a zeolite Y has been used. For all the mixtures, the influence of the operating conditions (time, temperature, pressure) and the effect they have on the yields of the fractions of interest (naphtha and light cycle oil), as well as on their composition, have been tested. In addition, special attention has been paid to the physicochemical phenomena that take place during the reactions in order to analyze the catalyst behaviour and the different causes of its deactivation with a view to its implementation in industrial units. The use of advanced analytical techniques has allowed to establish the compositional framework of all samples regardless of their heavy nature, which has allowed to determine the mechanisms of hydrocracking of plastics, as well as the routes of elimination of different families of compounds. Finally, kinetic modelling of these systems has been carried out for the optimization of the operating conditions by performing simulations aiming at the maximum conversion of the plastics and maximum yield of the target fractions, while minimizing the products of less interest.