Studying of Catalyst Deactivation in a Commercial Hydrocracking Process (ISOMAX)

Catalyst deactivation as usually indispensable , although the rate which it occurs varies greatly . at first this article discusses the causes of deactivation in a commercial hydrocracking unit, called isomax. then , a 5-lump kinetic model including of catalyst decay function for hydrocracking of vacuum gas oil in a commercial plant is proposed. the model considers vacuum gas oil vgo having boiling poit higher than 380c , diesel 260-380c , kerosene 150-260c, naphta ibp-150c, and gas as products. by using selective catalyst decay function in the kinetic model the effect of the catalyst deactivation on the yield of products during time is studied . the prediction of the model during 1.5 years is in good agreement with the actual commercial data. the average absolute deviation aad% of the model for the strategic products like naphtha , kerosene and diesel are about 1.784% , 1.983% and 1.971% , respectively. also it is observed that the estimated parameters are consistent with the reported characteristics of amorphous catalysts