Abstract: Self-heating characteristics of a spontaneously combustible catalyst are reduced by treating spontaneously combustible catalysts with oxygen-containing hydrocarbons having at least 12 carbon atoms. The treatment is particularly suitable for reducing the self-heating characteristics of sulfidable metal oxide(s)-containing catalysts, presulfurized catalysts, presulfided catalysts or reduced catalysts. When applied to sulfur-containing catalysts, the treatment gives a catalyst that has suppressed self-heating properties without substantially compromising sulfur retention or activity. Further hydrocracking catalysts treated by the oxygen-containing hydrocarbons give improved product yield. Further, a method of safely unloading a catalyst from a reactor is provided where the catalyst in the reactor is treated with a liquid mixture containing oxygen-containing hydrocarbon having at least 12 carbon atoms to wet the catalyst.

Abstract: Self-heating characteristics of a spontaneously combustible catalyst are reduced by treating spontaneously combustible catalysts with oxygen-containing hydrocarbons having at least 12 carbon atoms. The treatment is particularly suitable for reducing the self-heating characteristics of sulfidable metal oxide(s)-containing catalysts, presulfurized catalysts, presulfided catalysts or reduced catalysts. When applied to sulfur-containing catalysts, the treatment gives a catalyst that has suppressed self-heating properties without substantially compromising sulfur retention or activity. Further, a method of safely unloading a catalyst from a reactor is provided where the catalyst in the reactor is treated with a liquid mixture containing oxygen-containing hydrocarbon having at least 12 carbon atoms to wet the catalyst.

Abstract: Self-heating characteristics of a spontaneously combustible catalyst are reduced by treating spontaneously combustible catalysts with oxygen-containing hydrocarbons having at least 12 carbon atoms. The treatment is particularly suitable for reducing the self-heating characteristics of sulfidable metal oxide(s)-containing catalysts, presulfurized catalysts, presulfided catalysts or reduced catalysts. When applied to sulfur-containing catalysts, the treatment gives a catalyst that has suppressed self-heating properties without substantially compromising sulfur retention or activity. Further, a method of safely unloading a catalyst from a reactor is provided where the catalyst in the reactor is treated with a liquid mixture containing oxygen-containing hydrocarbon having at least 12 carbon atoms to wet the catalyst.

Abstract: The invention relates to an improved method of presulfurizing a sulfidable metal oxide(s)-containing catalyst which minimizes sulfur stripping upon start-up of a reactor and improves catalyst activity. The method consists of contacting a sulfidable metal oxide(s)-containing catalyst with elemental sulfur at a temperature such that said elemental sulfur is substantially incorporated in the pores of said catalyst by sublimation and/or melting and heating the sulfur-incorporated catalyst in the presence of a liquid olefinic hydrocarbon at a temperature greater than about 150.degree. C.

Abstract: Self-heating characteristics of a spontaneously combustible catalyst are reduced by treating spontaneously combustible catalysts with oxygen-containing hydrocarbons having at least 12 carbon atoms. The treatment is particularly suitable for reducing the self-heating characteristics of sulfidable metal oxide(s)-containing catalysts, presulfurized catalysts, presulfided catalysts or reduced catalysts. When applied to sulfur-containing catalysts, the treatment gives a catalyst that has suppressed self-heating properties without substantially compromising sulfur retention or activity. Further, a method of safely unloading a catalyst from a reactor is provided where the catalyst in the reactor is treated with a liquid mixture containing oxygen-containing hydrocarbon having at least 12 carbon atoms to wet the catalyst.

Abstract: The invention relates to an unproved method of presulfurizing a sulfidable metal oxide(s)-containing catalyst which minimizes sulfur stripping upon start-up of a reactor and improves catalyst activity. The method consists of contacting a sulfidable metal oxide(s)-containing catalyst with elemental sulfur at a temperature such that said elemental sulfur is substantially incorporated in the pores of said catalyst by sublimation and/or melting and heating the sulfur-incorporated catalyst in the presence of a liquid olefinic hydrocarbon at a temperature greater than about 150.degree. C.

Abstract: The invention relates to an improved method of presulfurizing a sulfidable metal oxide(s)-containing catalyst which minimizes sulfur stripping upon start-up of a reactor and improves catalyst activity. The method consists of contacting a sulfidable metal oxide(s)-containing catalyst with elemental sulfur at a temperature such that said elemental sulfur is substantially incorporated in the pores of said catalyst by sublimation and/or melting and heating the sulfur-incorporated catalyst in the presence of a liquid olefinic hydrocarbon at a temperature greater than about 150.degree. C.

Abstract: A mixture of shaped catalysts, catalyst supports or sorbents comprising generally cylindrical, free flowing particles of regular geometric shape having substantially the same diameter and of varying length are length graded into a first group of particles having a length below a predetermined length, L.sub.1, in the range of fromn 0.8 to about 24 millimeters and an L/D greater than one, and a second group of particles having a length greater than L.sub.1, by feeding the mixture into a rotating cylindrical drum having inwardly opening indentations in its cylindrical wall having a transverse diameter of substantially L.sub.1. The drum is rotated about its longitudinal axis at speeds sufficient to entrap in the indentations and convey particles having a length below L.sub.1 comprising the first group upwardly to a height permitting the particles to fall into a fixed, upwardly opening trough, while retaining the second group of particles having a length above L.sub.

Abstract: A spent hydrotreating catalyst having carbonaceous and metallic deposits comprising generally cylindrical, free flowing particles of regular geometric shape having substantially the same diameter but of varying length is stripped, length graded, density graded using an upward flow of gas through an inclined, vibrating surface, and regenerated to achieve catalyst activity very near that of a fresh catalyst.