Effect of diluent size on the performance of a micro-scale fixed bed multiphase reactor in up flow and down flow modes of operation

The comparative behaviors of a micro-scale fixed bed multiphase reactor in up flow and down how modes of operation were studied fur hydrodesulfurizati on of atmospheric gas oil over a commercial catalyst. The experiments for t he two modes of operation were conducted for a wide range of diluent size a nd other process variables such as liquid hourly space velocity and hydroge n/gas oil ratio. The results showed that the down how mode of operation usi ng 0.19 mm size of diluent could be used for generatings reliable and meani ngful data. On the other hand, the use of up flow mode of operation is rest ricted only for higher space velocities even while using 0.19 mm size of di luent. The results also indicated that the performance of the up flow mode of operation was poor at higher hydrogen/gas oil ratio. This change in perf ormance is pronounced when higher size of diluent was used with the catalys t. In contrary, the hydrogen/gas oil ratio had minimum effect on the perfor mance of the reactor for down flow mode of operation. (C) 2001 Elsevier Sci ence B.V. All rights reserved.