Trickle phase

Figure 6. Relationship between the Peclet particle and Reynolds particle numbers for single and trickle phase flow (adapted from Ref. 20).

Distillate hydrotreating cat-feed hydrotreater Trickle phase catalytic Remove S and N and saturate aromatics... 

Hydrocracker Trickle phase catalytic Convert gas oils, coker gas oil, and light catalytic cycle oil to lighter products... 

Residuum hydrotreater Trickle phase catalytic/thermal Convert heavy residuum to lighter distillates, removing metals (Ni, V), S, and N... 

The rate of acetone hydrogenation was determined in the trickle phase with a 120-ml tubular reactor using 20 ml of either 3-mm activated tablets or hollow spheres. This hydrogenation was performed at 5 bar hydrogen pressure, 75°C, a hydrogen-to-acetone ratio of 5-to-l, and at LHSV of 4.0 h. Acetone conversion and selectivities were determined by GC. 

Table 3 shows the activity data for the trickle phase hydrogenation of adiponitrile (ADN) at the LHSV of 1.03 and 0.26. The Co hollow spheres were far more active than the Co tablets on both a weight and volume basis due to the increased porosity of the hollow spheres. Adding Cr and Ni dopants to the Co / Al alloy did not change the activity of the Co hollow spheres, however preadsorbing LiOH on the Cr and Ni doped Co hollow spheres did increase its activity at the LHSV h" of... 

As shown in Figure 12, the hydrogenation of l,4-dihydroxy-2-butyne (ByD) occurs stepwise via formation of the l,4-dihydroxy-2-butene (BeD) to the desired product 1,4-butanediol (BDO). Table 6 displays the trickle phase reaction data for the catalysts studied here at 135°C and 60 bar. The use of higher pressures and lower temperatures (e.g., 266 bar and 75°C (31)) would provide higher selectivi-ties, however the conditions used here were chosen to make the reaction more demanding so that we could better differentiate between the various catalysts. 

To describe trickle flow of particles in the reactor, Verver and van Swaaij [37] proposed a three-phase model, the respective phases being particle-free gas phase, gas-solids suspension, and catalyst. Within the gas-solids suspension phase, diffusion of the reactants is parallel to the reaction, which occurs on the catalyst. Mass transfer occurs in the zone between the gas phase and the outer surface of the suspension phase. According to the trickle-phase model, the overall rate constant can be dehned as ... 

These processes, which use catalytic fixed beds, are claimed to be operated in the gas phase, and so they are not relevant to this review 9). But, very similar processes are operated in the trickle phase. For example, fatty amines can be obtained by reacting ammonia and fatty alcohols (58). 

Bondi A. Handling kinetics from trickle-phase reactors. Chem. Technol. 1971 1 185-188. 

The solid trickle phase column A column is filled with Raschig rings, or a similar packing, and a good fluidizable powder is introduced continuously at the top. Gas passes upward through the column. The powder flows downward over the packing surface. A very effective countercurrent mass transfer can be obtained in this manner (Roes, 1979). 

Rothfeld, L. B. and J. L. Ralph. Equivalence of Pulse and Step Residence Time Measurements in a Trickle-Phase Bed. 

De Bruijn, A. Testing of HDS Catalysts in Small Trickle-Phase Reactors. Sixth International Congress of Cat. Proc. (Fundan) (1977) 951-964. 

Bondi, A, "Handling Kinetics from Trickle-Phase Reactors",... 

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