Hydrocarbon conversion process with annular guard beds

Claim 1

A catalytic hydrocarbon conversion process to more efficiently prevent plugging of the inlet surface of the catalyst bed which comprises the steps of: (a) passing a feed stream comprising hydrogen and hydrocarbonaceous reactants into an upper end of a reaction zone maintained at hydrocarbon conversion conditions; (b) dividing the feed stream into a number of portions and passing each portion through one of a plurality of separated annular beds of particulate material located within the upper one-third of the reaction zone, with the annular beds of particulate material being radially spaced apart, concentric about the vertical major axis of the reaction zone and located at substantially the same vertical elevation within the reaction zone, and with the flow of the feed stream through each of the annular beds of particulate material being inward through both cylindrical sides of at lease an upper portion of the annular bed and outward through a lower portion of the annular bed; (c) recombining the portions of the feed stream at a point below the annular beds of particulate material; (d) passing the feed stream downward through a cylindrical bed of catalyst which is at least four times greater in volume than the particulate material contained within the annular beds; and, (e) removing a reaction zone effluent stream from a lower portion of the reaction zone.