Abstract: Economies in capital cost and operation of a hydrocarbon refining unit for desulfurization of diesel fuel are provided by a heat exchange sequence which eliminates the need for a fired heater on the product fractionation zone. The feed to the fractionation zone is heat exchanged twice against both the effluent bottoms stream of the fractionation zone and the reaction zone effluent stream.

Abstract: An improved process is disclosed for the removal of nitrogen compounds from light hydrocarbon streams. Such nitrogen removal enhances the performance of catalytic processes which upgrade light hydrocarbons, especially light olefins, such as isomerization and etherification. The nitrogen-removal process can usefully be combined with steps for removal of sulfur compounds and highly unsaturated compounds in a process combination for upgrading the light hydrocarbons.

Abstract: This invention relates to a process for improving the activity of a catalyst effective in sweetening a hydrocarbon fraction containing mercaptans. The process involves adding to the hydrocarbon fraction an effective amount of an aqueous solution comprising ammonium hydroxide, a metal chelate and an onium compound.

Abstract: Fuel gas streams containing oxygen are treated by a process that performs simultaneous sweetening and absorption of mercaptan compounds. The mercaptan oxidation catalyst and an aqueous alkaline solution and a low vapor pressure liquid hydrocarbon stream contact the fuel gas feed in a mixing vessel to sweeten the mercaptans and absorb resulting disulfides from the gas stream into the liquid hydrocarbon stream. A separation vessel receives the dual phase effluent from the mixing vessel and settles the effluent into three component phases. An upper gas phase provides a treated fuel gas stream, an intermediate hydrocarbon phase provides liquid hydrocarbons containing disulfides for removal from the process, and recycle to the mixing vessel and an alkaline solution drains from the bottom of the settler. The aqueous alkaline solution is pumped back to the mixing vessel in combination with the mercaptan oxidation catalyst.

Abstract: This invention relates to a catalyst which is useful in oxidizing mercaptans present in a sour hydrocarbon fraction. The catalyst consists of an aqueous solution containing ammonium hydroxide, a metal chelate and an onium compound selected from the group consisting of quaternary ammonium, phosphonium, arsonium, stibonium, oxonium and sulfonium compounds. The counter ion of the onium compound is halide, nitrate, sulfate, phosphate, acetate, citrate and tartrate. The catalyst is used in a liquid-liquid process to sweeten a sour hydrocarbon fraction.

Abstract: This invention relates to a liquid-liquid process for treating a sour hydrocarbon fraction. The process comprises contacting the hydrocarbon fraction in the presence of an oxidizing agent with an aqueous solution containing ammonium hydroxide, a metal chelate and an onium compound selected from the group consisting of quaternary ammonium, phosphonium, arsonium, stibonium, oxonium and sulfonium compounds. A preferred onium compound is a quaternary ammonium compound with an especially preferred compound being a quaternary ammonium halide.

Abstract: This invention relates to a liquid-liquid process for treating a sour hydrocarbon fraction. The process comprises contacting the hydrocarbon fraction in the presence of an oxidizing agent with an aqueous solution containing ammonium hydroxide, a metal chelate and an onium compound selected from the group consisting of quaternary ammonium, phosphonium, arsonium, stibonium, oxonium and sulfonium compounds. A preferred onium compound is a quaternary ammonium compound with an especially preferred compound being a quaternary ammonium halide. This invention also relates to a catalyst comprising an aqueous solution containing ammonium hydroxide, a metal chelate and an onium compound, for oxidizing mercaptans contained in a sour hydrocarbon fraction. The aqueous solution which is the catalyst can also be used to improve the activity of a fixed bed mercaptan oxidation catalyst.

Abstract: Although high naphthenic acid hydrocarbon feedstocks normally need to be washed with caustic prior to being sweetened in a fixed bed mercaptan-to-disulfide oxidation process to avoid bed plugging, the prewash can be eliminated if aqueous ammonia is used concurrent with and as a part of the sweetening process. Aqueous ammonia injected into a sour hydrocarbon stream prior to the sweetening zone not only eliminates bed plugging, but affords an aqueous phase from which naphthenic acids may be recovered easily and economically. The ammonia also can be recovered for reuse, affording a process with considerably enhanced economic return.

Abstract: This invention relates to a process for sweetening a sour hydrocarbon fraction containing mercaptans. The process involves contacting the hydrocarbon fraction in the presence of an oxidizing agent with a catalytic composite, ammonium hydroxide and a quaternary ammonium hydroxide. There is a synergistic effect between the ammonium hydroxide and the quaternary ammonium hydroxide. Use of ammonium hydroxide instead of an alkaline hydroxide allows the waste stream to be re-used in other parts of the refinery, and allows for easier disposal of the waste stream.

Abstract: A process is disclosed for removing mercaptans from highly olefinic feed streams by extraction with an aqueous alkaline solution. The aqueous solution is preferably regenerated by oxidation of extracted mercaptans to disulfides. The invention employs two extraction steps performed on the aqueous solution to limit the passage of olefins or acetylenes into the mercaptan conversion zone and to limit the passage of mercaptans and/or oxygenates into the primary extraction zone.

Abstract: A liquid-liquid contacting apparatus is disclosed. The apparatus is useful in extracting mercaptans from a hydrocarbon stream such as cracked gasoline by nonturbulent countercurrent contacting of the hydrocarbon stream with an aqueous caustic solution. The denser liquid phase flows downward from an upper phase separation zone through a connecting cylindrical contacting zone into a lower phase separation zone. Liquid withdrawal and addition means communicate with each separation zone. A mass of fibrous contacting strands is suspended in the contacting zone. The contacting strands are preferentially wetted by either of the two liquid phases to provide a large surface area which enhances extraction capacity.

Abstract: A process is disclosed for treating hydrocarbon streams by the catalyzed oxidation of mercaptans to disulfides. In the process, the hydrocarbon-containing stream is admixed with air and then passed through an oxidation zone. The oxidation zone effluent is decanted to remove an aqueous alkaline solution in a high pressure separation zone. It is then depressurized into a low pressure separator in which dissolved excess nitrogen and oxygen are substantially removed from the hydrocarbons. The treated hydrocarbons are then pressurized to force their flow into a low pressure product receiving facility. This sequence eliminates or minimizes the discharge of gaseous nitrogen and oxygen and hydrocarbon vapors in the storage facility, where they are pollution abatement problems and possible safety hazards.

Abstract: A process is disclosed for treating hydrocarbon streams such as naphtha by the oxidation of mercaptans into disulfide compounds which remain in the hydrocarbon stream. The conversion is effected during passage of the hydrocarbon and an aqueous stream downward through a cylindrical mass of liquid-liquid contact material. The liquids then flow through a cylindrical screen into an annular separation zone which surrounds a lower part of the contact material. After decantation in the separation zone, the aqueous material, which preferably contains the oxidation catalyst, is recycled.

Abstract: An improved process is disclosed for removing trace acidic compounds from liquid hydrocarbons. Traces of acidic compounds, including carboxylic acids, H.sub.2 S, naphthenic acids, et al., are present in most hydrocarbon streams. The presence of these acidic compounds is considered deleterious to accepted product specifications. The trace acidic compounds which interfere are removed via injection of a dilute aqueous alkaline solution into the hydrocarbon stream and passage of this stream through a coalescing bed.

Abstract: A process is disclosed for the preparation of a solid bed catalyst system which comprises treating a charcoal-containing solid support with steam and a substantially inert gas at a temperature of from about 800.degree. F. to about 950.degree. F. for a period of time comprising from about 2 hours to about 6 hours, drying the treated bed and impregnating the dried charcoal-containing solid support with from about 0.001 weight percent to about 10.00 weight percent of a metal phthalocyanine compound.

Abstract: A method is disclosed for the treatment of a petroleum charge stock which comprises the treatment of said petroleum charge stock with an aqueous solution containing a metal phthalocyanine compound and a compound selected from the group consisting of an alkali metal sulfide and an alkali metal sulfite.