Abstract: Minor amounts of C.sub.3 -C.sub.4 hydrocarbons from amine absorbents used in removing H.sub.2 S liquid C.sub.3 -C.sub.4 hydrocarbon are recovered. The process features recovery of the C.sub.3 -C.sub.4 hydrocarbon in a hydrocarbon gas from a second absorption zone where H.sub.2 S is removed from the hydrocarbon gas, the hydrocarbon gas functioning as a stripping gas.

Abstract: Novel riser reactor design with associated multiple feed inlet means for contacting regenerated catalyst particles with low quality naphtha, C.sub.5 minus wet gas product of hydrocarbon conversion and a residual oil feed comprising components boiling above about 1025.degree. F. and comprising metal contaminants. Low quality naphtha from thermal cracking is charged either separately or in admixture with C.sub.5 and lower boiling wet gas product of hydrocarbon conversion to the bottom portion of the riser conversion zone for contact with freshly regenerated zeolite cracking catalyst. The vaporous material thus charged conveys the regenerated catalyst at an acceptable velocity to an expanded section of the riser wherein residual oil is charged by a plurality of nozzle means penetrating the wall of the riser in the transition section to the expander user section.

Abstract: The method and means for effecting selective visbreaking of residual oil feeds comprising metallo-organic compounds with a fluid solid sorbent particle material in the presence of process sour water and wet gas recycle material is described to provide a gas oil rich product more suitable for crystalline zeolite fluid catalytic cracking operations.