Towards modelling production of clean fuels: Sour gas formation in catalytic cracking

Abstract

Although one important by-product of fluidised-bed catalytic cracking of hydrocarbons is the sour gas (mainly hydrogen sulfide), there are no kinetic models to predict its generation. Moreover, if feedstock sulfur is not directed to sour gas, it will be present in gasoline, cycle oils and coke. These products are used as fuels, which could emit sulfur oxides during their combustion. In order to be able to model production of clean fuels, a kinetic scheme that considers sour gas as unmatched product was developed; meanwhile, the sulfur distribution in cracking products is predicted. Model parameters are validated using industrial operating data. This kinetic scheme is employed to model steady state operation of an industrial catalytic cracking riser and to find operating conditions that diminish the sulfur content in fuels. © 2004 Society of Chemical Industry.