| The hydrocracking catalyst system is known to deactivate during normal operations. The rate of deactivation depends on run conditions. As a result, the run temperature is gradually increased to compensate for the deactivation. The kinetic model developed by Ashok Krishna and a curve fitting program were used to treat the temperature-time data. T =ln1-t/z /Q+1/To -1 where: z=exp Ed/RTo/Ad Ed/Ea -n+ 1,Q =&parl0;Ed-nE a+Ea&parr0; /R ; This equation was used at different hydrogen partial pressures to obtain n, the activation energy of deactivation (Ed) and the pre-exponential (Ad) for four catalyst systems. These parameters were in turn used to calculate catalyst life. The results showed that the governing equation did describe the pilot plant data. Three out of the four systems were 1 st order kinetic mechanism and the other was 2nd order. A relationship between Ad, Ed, and hydrogen partial pressure was also observed. |
