Reactor design for polyisobutylene succinic anhydride production, coal liquefaction, used oil and waste plastics pyrolysis

A reactor system is developed for the continuous production of polyisobutylene succinic anhydride (PIBSA) which is the starting material for the most important class of lubricant additive components. The basic reaction mechanism and the reaction kinetics are first investigated and the appropriate reaction conditions are derived that would be needed for a medium sized production plant. The side reaction of the formation of tarry products from the maleic anhydride reactant was also considered. A loop reactor process was arrived at to minimize the coke formation as well as to increase the mass transfer procees between the two reactants. Proper selection of the pump type was also a very important engineering design task given the tendency for coke accumulation at the pump and the need to increase the mixing between the loop reaction sections so as to maximize the desired reaction.; The coking reaction is studied separately. The appropriate reaction, diffusion and deposition steps are considered and a system is designed that consists of a conical section that ensures an increase in velocity from entrance to exit. This results in different rates of deposition at the entrance where the velocity is lower to the outlet where the velocity is much higher. The reaction of deposition is carried out at different temperatures. An appropriate mechanism for the coking and deposition reactions is obtained.; Waste oil coprocessing with coal results in high coal conversions. This could be due to the fact that the low molecular weight free radicals that are formed from the coal result in combination products that have lesser coke forming propensity than those formed from free radicals formed from coal alone.; Another reason for the good performance of the used oil as a coal solvent may be its dispersing powers obtained by virtue of the presence of surfactants. The effects of surfactants on coal liquefaction is separately considered and increases in conversions above 10-15% are obtained.; Coprocessing of coal with waste plastics is carried out. The results show that plastics addition to the solvent coal results in increases in conversion and selectivity. The conversions further increase if the plastics and the oil are further prepyrolysed prior to introduction into the liquefaction reactor.; Pyrolysis of used oil is an important recycling issue. So is the pyrolysis of waste plastics that are not recyclable as a polymer. A pyrolysis reactor is designed that is sufficiently compact to be used on a small scale to treat locally generated oil and plastics wastes. This two stage heating system provides sufficient control of the pyrolysis extent to tailor reaction conditions to the raw materials that are to be processed. The economics of the process are then considered to show that the pyrolysis is an economically and technically feasible process.