Abstract: The milling cutter of the invention comprises a cutting section having a plurality of blades positioned on the surface and separated one from the other by flutes. At least two blades have one or more smooth segments, exhibiting an even and unbroken land and cutting edge, interspersed with one or more serrated segments containing a row of cutting teeth. The positions of the smooth and serrated segments are staggered from blade to blade so that in the course of one complete revolution of the cutter, each point along a surface being worked by the cutter will be contacted by at least one smooth segment and at least one serrated segment.

Abstract: Circulating oil used for removal of sulfur in sour gas wells is contacted with an aqueous solution of a lower polysulfide of an alkali metal or ammonia to form a higher polysulfide of the alkali metal or ammonia, and the oil is separated from the higher polysulfide. The higher polysulfide is converted to lower polysulfide by precipitating part of the sulfur contained therein, and the lower polysulfide is recycled for oil desulfurization.

Abstract: Hydrated alkali metal sulfides used to remove sulfur from fossil fuels to form alkali metal polysulfides which are recycled to alkali metal sulfides and elemental sulfur by thermal or thermal reduced pressure decomposition of the alkali metal polysulfides or by conversion of the hydrolysis products entirely by H.sub.2 S.

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: Petroleum residues are reduced in sulfur content by intimately contacting one volume of petroleum residue with at least 0.25 volume of alkali metal sulfide hydrate melt, or alkali metal hydroxide hydrate melt or mixtures thereof, within a closed system, at a temperature between 120.degree. C. and 325.degree. C., for from 3 to 60 minutes, thereafter separating de-sulfured petroleum residue from said alkali metal sulfide hydrate melt by a hot liquid-liquid separation, thereafter utilizing said separated alkali metal sulfide hydrate melt to de-sulfur additional petroleum residue.

Abstract: Sulfur-containing heavy hydrocarbonaceous oil feeds are simultaneously hydroconverted and desulfurized by reaction of the feed with an alkali metal alkoxide in the presence of added hydrogen at elevated temperatures.

Abstract: High efficiency in liquid-liquid extraction operations, such as extracting mercaptans from hydrocarbons with caustic, is obtained over a wide range of flow rates through a single extraction column by the provision of an intermediate product drawoff means located between a downstream section of extraction trays having greatest efficiency at low throughputs and an upstream section of trays having peak efficiency at high throughputs. A second product stream is removed after passing through the low flow rate trays and is blended with the stream from the intermediate drawoff means.

Abstract: Improved processes for the combined desulfurization and hydroconversion of various sulfur-containing pertroleum oils, and particularly various residua feedstocks, are disclosed. These feedstocks are thus contacted with alkali metals, such as sodium, in the molten state, in a conversion zone maintained at specified conditions such that the feedstocks are both desulfurized and subjected to significant hydroconversion, particularly demonstrated by significant reductions in the 1,050.degree. F+ fraction of these feedstocks, as well as significantly decreased Conradson carbon and increased API gravity. In addition, the deep demetallization and moderate denitrogenation of these feedstocks is also achieved. These important results are obtained by maintaining the conversion zone at temperatures of above 750.degree. F, and in the presence of sufficient added hydrogen to produce a hydrogen pressure in the conversion zone of between about 1500 and 3000 psig.

Abstract: Coal and petroleum oils, flue gases produced by their combustion, and natural gases are desulfurized by reacting with sulfides or polysulfides of hydrogen, sodium, potassium, rubidium or cesium to form the higher sulfur content polysulfides of these metals. After these sulfides have acquired sufficient sulfur in combined form to form sulfur saturated polysulfides, they can be reduced to sulfur unsaturated forms with recovery of elemental sulfur. In their sulfur unsaturated form, these metal polysulfides are used to treat additional quantities of the fossil fuels.The metal sulfides or polysulfides can be used in 1 to 12% aqueous solution or in melt condition. Hydrogen polysulfides are used in their liquid form.Sulfur removal from the fossil fuels takes place by dissolving and/or reacting elemental sulfur, many organic sulfur forms, and water-insoluble metal sulfides in aqueous solutions of alkali metal sulfides or in melts of alkali metal sulfides.

Abstract: Sulfur-containing petroleum oil feedstocks which include heavy hydrocarbon constituents undergo simultaneous desulfurization and hydroconversion by contacting and reacting such feedstocks with sodamide in the presence of hydrogen and at elevated temperatures. The mixture of reaction products resulting from the above procedure is separated to give a sodium sulfur salt by-product, and a petroleum oil product which has been substantially desulfurized and demetallized, as well as being significantly improved as indicated by a reduced Conradson carbon content and an increased API gravity relative to the feedstock. Sodamide is regenerated from the sodium sulfur salt by-product and can be recycled for reaction with additional feedstock.

Abstract: Heavy carbonaceous feeds, including various sulfur-containing heavy petroleum oils, are simultaneously desulfurized and subjected to hydroconversion by contacting these feedstocks with alkali metal oxides in a conversion zone maintained at elevated temperatures and in the presence of hydrogen. In this manner, the feeds are substantially desulfurized, and significant upgrading of the feedstocks is also obtained as demonstrated by decreased Conradson carbon, increased API gravity, and conversion of a substantial portion of the 1,050.degree. F+ portion of the feedstream. In addition, methods for the regeneration of the alkali metal oxides from the alkali metal sulfide salts produced in the reaction zone are disclosed.

Abstract: Sulfur-containing petroleum oil feedstocks which include heavy hydrocarbons constituents undergo simultaneous desulfurization and hydroconversion by contacting such feedstocks with sodamide in the presence of hydrogen and at elevated temperatures. The mixture of reaction products resulting from the above procedure can be separated to give sodium sulfur salts and a petroleum oil product which has been substantially desulfurized and demetallized and significantly upgraded as demonstrated by a reduced Conradson carbon content and an increased API gravity.

Abstract: Heavy petroleum oils, preferably whole crude or residua, are desulfurized and upgraded by contacting the petroleum oil with sodium oxide in the presence of hydrogen at elevated temperatures. The resulting mixture comprising desulfurized petroleum oil and a dispersion of sodium salts, primarily sodium sulfide and sodium hydroxide, is separated by conventional means and sodium oxide is regenerated from the salts.

Abstract: Processes for the simultaneous desulfurization and hydroconversion of heavy carbonaceous feeds, including various sulfur-containing heavy petroleum oils, are disclosed. These feeds are contacted with alkali metal hydroxides in a conversion zone, in the presence of added hydrogen, and at elevated temperatures, whereby the feeds are substantially desulfurized, while at the same time significant upgrading of these feedstocks is obtained as demonstrated by decreased Conradson carbon, increased API gravity, and the conversion of a substantial portion of the 1,050.degree. F+ portion of the feedstream. In addition, methods for the regeneration of alkali metal hydroxides from the alkali metal salts produced in the conversion zone are disclosed.

Abstract: Sulfur-containing petroleum oil feedstocks which include heavy constituents undergo both desulfurization and hydroconversion by contacting such feedstocks with sodium hydride in the presence of hydrogen, at elevated temperatures. The mixture of reaction products resulting from the above procedure can be separated to give a petroleum oil product which has been desulfurized and demetallized and has a reduced Conradson carbon content and an increased API gravity relative to the feedstock, and a by-product of sodium sulfide salt.

Abstract: A method of reducing the sulfur and nitrogen content of a hydrocarbon, specifically, a liquid or gaseous phase hydrocarbon which comprises contacting the hydrocarbon with nahcolite in an amount effective to remove sulfur and nitrogen compounds from the hydrocarbon. The nahcolite containing combined sulfur and nitrogen can be removed from the hydrocarbon, producing a hydrocarbon having a reduced sulfur and nitrogen content.The method is particularly applicable to the reduction of the sulfur and nitrogen content in shale oil by contacting shale oil and nahcolite in a shale oil retort or process.