Abstract: A method for producing a kerogen concentrate from oil shale comprises treating shale with an aqueous caustic treating solution to produce a shale product of substantially transformed mineral content, and then treating the shale product with an aqueous acid solution to produce a kerogen concentrate. The acid solution extracts minerals from the shale product to lower the ash content of the kerogen concentrate. A spent acid solution containing the extracted minerals can be treated to recover minerals therefrom.

Abstract: A method for producing a kerogen concentrate from oil shale comprises treating shale with a first aqueous caustic treating solution to produce a shale product of substantially transformed mineral content, and then treating the shale product with an aqueous acid solution to produce a first kerogen concentrate. The acid solution extracts minerals from the shale product to make a low ash content first kerogen concentrate. A spent acid solution containing the extracted minerals can be treated to recover minerals therefrom. The first kerogen concentrate is then treated with a second aqueous caustic treating solution to produce a second kerogen concentrate of lower ash content. The first and second aqueous caustic treating solutions are preferably the same.

Abstract: Disclosed is a method for detecting the flame front during the in situ combustion of a subterranean carbonaceous stratum which involves providing one or more radio transmitters below the surface of the ground, each of said transmitters being capable of sensing and transmitting information concerning the physical and chemical properties of its surroundings, and monitoring said transmissions as an indication of the extent and movement of said flame front. Also disclosed is a method for detecting non-uniform packing characteristics of rubblized material which involves providing one or more radio transmitters within the boundaries of a retort capable of sensing and transmitting information concerning the physical parameters of its surroundings, and monitoring said transmissions as an indication of the size and density distributions of the rubble in said retort.

Abstract: Disclosed is a method for detecting the flame front during the in situ combustion of a subterranean carbonaceous stratum which involves providing at least one multi-turn coil of wire on the surface of the ground electrically connected into one or more circuits in which an electrical resonance condition is established, and monitoring the change in impedance in one or more of said circuits as an indication of the extent and movement of said flame front.

Abstract: Disclosed is a method for detecting the flame front in the in situ combustion of a subterranean carbonaceous stratum which comprises providing two or more resistance probes inserted into the ground electrically connected in one or more circuits capable of measuring the resistance between pairs of said probes, and monitoring the change in resistance in one or more of said circuits as an indication of the extent and movement of said flame front.

Abstract: Disclosed is a method for detecting the flame front during the in situ combustion of a subterranean carbonaceous stratum which involves providing one or more radio transmitters below the surface of the ground, each of said transmitters being capable of sensing and transmitting information concerning the physical and chemical properties of its surroundings, and monitoring said transmissions as an indication of the extent and movement of said flame front. Also disclosed is a method for detecting non-uniform packing characteristics of rubblized material which involves providing one or more radio transmitters within the boundaries of a retort capable of sensing and transmitting information concerning the physical parameters of its surroundings, and monitoring said transmissions as an indication of the size and density distributions of the rubble in said retort.

Abstract: A process for recovering and upgrading hydrocarbons from oil shale by contacting the oil shale solids in the presence of an acidic or oxidative catalytic substance with a water-containing fluid at a temperature in the range of from at least 705.degree. F., the critical temperature of water, to about 900.degree. F., in the absence of externally supplied hydrogen, wherein the water has a density of at least 0.15 gram per milliliter. Examples of such acidic or oxidative catalytic substance are molecular oxygen, sodium bisulfate, sodium bisulfite, and carbon dioxide.

Abstract: A process for recovering and upgrading hydrocarbons from tar sands by contacting the tar sands with a dense-water-containing fluid at a temperature in the range of from about 600.degree. F. to about 900.degree. F. in the absence of an externally supplied catalyst and hydrogen, and wherein the density of the water in said fluid is at least 0.10 gram per milliliter.

Abstract: A process for upgrading a hydrocarbon fraction by contacting the hydrocarbon fraction with a dense-water-containing fluid at a temperature in the range of from about 600.degree. F. to about 900.degree. F. in the absence of an externally supplied catalyst and hydrogen and of pretreatment of the hydrocarbon fraction.

Abstract: A process for recovering and upgrading products from solid coal by contacting the coal with a dense-water-containing fluid at a temperature in the range of from about 600.degree. F. to about 900.degree. F. in the absence of externally supplied hydrogen or other reducing gas and in the presence of a sulfur-resistant catalyst.

Abstract: A process for recovering and upgrading products from solid coal by contacting the coal with a dense-water-containing fluid at a temperature in the range of from about 600.degree.F. to about 900.degree.F. in the absence of externally supplied hydrogen or other reducing gas and in the presence of a sulfur- and nitrogen-resistant catalyst. The density of water in the water-containing fluid is at least 0.10 grams per milliliter, and sufficient water is present to serve as an effective solvent for the recovered liquids and gases.

Abstract: A process for recovering and upgrading products from solid coal by contacting the coal with a dense-water-containing fluid at a temperature in the range of from about 600.degree.F. to about 900.degree.F. in the absence of an externally supplied catalyst and hydrogen or other reducing gas.The density of water in the water-containing fluid is at least 0.10 grams per milliliter, and sufficient water is present to serve as an effective solvent for the recovered liquids and gases.

Abstract: A process for upgrading a hydrocarbon fraction and for generating hydrogen in situ by contacting the hydrocarbon fraction with a dense-water-containing fluid at a temperature in the range of from about 600.degree. to about 900.degree.F. in the absence of externally supplied hydrogen and of pretreatment of the hydrocarbon fraction and in the presence of a catalyst system containing a sulfur- and nitrogen-resistant catalyst.

Abstract: A process for upgrading a hydrocarbon fraction by contacting the hydrocarbon fraction with a dense-water-containing fluid at a temperature in the range of from about 600.degree.F. to about 900.degree.F. in the absence of externally supplied hydrogen and of pretreatment of the hydrocarbon fraction and in the presence of a sulfur-resistant catalyst.

Abstract: A process for recovering and upgrading hydrocarbons from oil shale and tar sands by contacting the oil shale or tar sands with a dense-water-containing fluid at a temperature in the range of from about 600.degree.F. to about 900.degree.F. in the absence of supplied hydrogen and in the presence of a sulfur- and nitrogen-resistant catalyst and wherein the density of the water in said fluid is at least 0.10 gram per milliliter.

Abstract: A process for recovering and upgrading hydrocarbons from oil shale and tar sands by contacting the oil shale or tar sands with a dense-water-containing fluid at a temperature in the range of from about 600.degree.F. to about 900.degree.F. in the absence of externally supplied hydrogen and in the presence of a sulfur-resistant catalyst and wherein the density of the water in said fluid is at least 0.10 gram per milliliter.