Showing papers on "Partial oxidation published in 1985"

Synthesis of ethylene and ethane by partial oxidation of methane over lithium-doped magnesium oxide

Abstract: The partial oxidation of methane into more useful chemicals such as methanol, ethylene and benzene has been investigated extensively, although yields for these products have been poor1–4. Moreover, in several of these processes the required oxidant is N2O rather than O2. Recent work5 in our laboratory has demonstrated that lithium-doped magnesium oxide (Li/MgO) in the presence of O2 has high activity for abstracting H from CH4 to form ·CH3 radicals. This suggests that C2H6 and C2H4 (C2 compounds) are produced by a coupling between two gaseous ·CH3 radicals formed on this catalyst. We report here our success in converting CH4 to C2 compounds in high yields in conventional catalytic conditions.

Electrochemical production of partially oxidized organic compounds

Abstract: A process for the selective production of partially oxidized organic compounds at the catalytic anode of a fuel cell wherein oxide anions formed at the fuel cell cathode by ionization of oxygen containing gas are transported by a molten salt oxygen containing electrolyte to the catalytic anode where selective partial oxidation of organic compounds is facilitated by the catalytic anode. Suitable catalytic anodes include catalysts selected from elements of the Periodic Table appearing in a group selected from the group consisting of Group IB, IIB, IIIA, VB, VIB, VIIB and VIII, in metallic oxide or cermet form. The process of this invention is particularly useful in the production of methanol by partial oxidation of methane.

Process for producing synthesis gas by partial combustion of hydrocarbons

Abstract: Process for production of synthesis gas in which a saturated hydrocarbon and an oxygen containing gas having a ratio of hydrocarbon to oxygen of greater than the stoichiometric ratio for complete combustion are introduced into a bed of particulate material. The bed comprises material which is catalytically active for partial oxidation and/or steam reforming reactions. The upward flow rate of the hydrocarbon/oxygen containing gas stream is sufficiently large to cause a spouting action of the bed material. The hydrocarbon and oxygen react together and the products of the reaction are withdrawn.

Process for the treatment of sulfur containing gases

Abstract: Process of treating sulfur containing gas streams by the Claus reaction in which a recycle stream containing a reactive component is employed in a negative feedback mode to maintain the sulfur producing Claus reaction at approximately equilibrium conditions. The feedstream may contain hydrogen sulfide or sulfur dioxide in a minor amount in an inert gas background. In one embodiment the feedstream to the reaction zone contains a stoichiometrically excess amount of sulfur dioxide for the Claus reaction. Effluent from the reaction zone is passed to a hydrogenation zone where the sulfur dioxide is converted to hydrogen sulfide. Hydrogen sulfide is extracted from the hydrogenation zone effluent and recycled to the Claus reaction zone. In another embodiment the feedsteam may contain a stoichiometrically excess amount of hydrogen sulfide. Effluent from the reaction zone is treated to produce a hydrogen sulfide containing recycle stream which is then subject to at least partial oxidation to produce a converted stream containing sulfur dioxide. The converted stream is recycled to the reaction zone. The invention may be employed in the high pressure processing of hydrocarbon gases containing sulfur.

Method of cooling partial oxidation gas containing finely divided impurities and used for combustion in a combined gas-steam turbine of a power plant

Abstract: A method of cooling partial oxidation gas entraining finely divided impurities employs nitrogen obtained as a by-product in a low temperature air decomposing plant delivering oxygen into a gasifier where a fuel is partially oxidized at a temperature above slag melting point. Crude gas exiting from the gasifier is quenched by the admixture of nitrogen to a temperature immediately below the fusing of softening point of dust particles entrained in the crude gas. Then the mixture is indirectly cooled in a waste heat boiler and subsequently additionally cooled in a second gas quencher by the admixture of further nitrogen. Nitrogen remains admixed to the gas during subsequent separating and desulphurizing treatment and is also supplied in the combustion chamber of a gas turbine.

Process for feeding and gasifying solid carbonaceous fuel

Abstract: A partial oxidation process for the production of a stream of mixed gases comprising H 2 and CO. An aqueous particulate solid carbonaceous fuel slurry feedstream is preheated by indirect heat exchange with a process-derived stream of skimmed gases substantially comprising H 2 O. The aqueous carrier of the slurry is vaporized by introducing superheated steam directly into the slurry pipeline. A suspension of particulate solid carbonaceous fuel entrained in a gaseous mixture substantially comprising steam e.g. about 90 to 99.9 wt. % H 2 O and about 0.1 to 10 wt. % of a CO 2 -containing gas mixture is produced. The suspension of solid fuel in the gaseous mixture is then separated in a skimming operation into an overhead gas stream substantially comprising steam, as previously described, and a bottom stream comprising particulate solid carbonaceous fuel with the remainder of said gaseous mixture. The bottom stream from the skimming operation is introduced into the reaction zone of a partial oxidation gas generator in admixture with a free-oxygen containing gas and with or without a temperature moderator where a gaseous stream comprising H 2 +CO is produced. In one embodiment, the temperature of the suspension of solid carbonaceous fuel feed stream entering the partial oxidation reaction zone by way of a burner is monitored. An increase in temperature would flag the back-flow of synthesis gas or oxygen into the burner. When this happens, the feedlines to the burner and the overhead gas stream from the cyclone separator may be automatically shut down to prevent thermal damage to the system.

Iron/lithium--promoted catalysts for the production of maleic anhydride

Abstract: Catalysts useful for the partial oxidation of nonaromatic hydrocarbons, particularly n-butane, with molecular oxygen or an oxygen-containing gas in the vapor phase to produce maleic anhydride are provided which comprise phosphorus, vanadium, and oxygen and a promoter component containing each of iron and lithium.

Process for preparing ammonia

Abstract: In a process for preparing ammonia from hydrogen and nitrogen the synthesis gas mixture is produced by partial oxidation, in the presence of a suitable catalyst, at a pressure of from 35 to 150 bar and temperatures of from 850°-1200° C. at the exit of the partial oxidation zone, followed by removal of the carbon oxides and water from the gaseous effluent of the partial oxidation zone. The air used for the catalytic partial oxidation is supplied in such a quantity that the molar ratio of hydrogen to nitrogen in the synthesis gas is between 2.5 and 3 to 1 and is enriched with such a quantity of oxygen that the total quantity of oxygen is sufficient to effect the required degree of hydrocarbon conversion.

Partial oxidation apparatus

Abstract: An apparatus is provided for the partial oxidation of a high metals or ash containing liquid hydrocarbonaceous fuel or a slurry of solid carbonaceous fuel to simultaneously produce saturated and unsaturated raw streams of synthesis gas, reducing gas, or fuel gas. Two continuous partial oxidation reactions in two separate reaction zones go on simultaneously. The fuel feed to the first partial oxidation zone is said fresh high metals or ash containing fuel. The raw product gas stream from the first partial oxidation zone is split into first and second split gas streams. The first split gas stream may be cooled in a radiant and/or convection type gas cooler without fouling heat exchange surfaces. The fuel feed to the second partial oxidation zone is a pumpable slurry which is prepared from the entrained matter that is separated from said gas streams during quench cooling and cleaning operations and which contains a comparatively high amount of metals and/or ash. The partial oxidation reaction takes place in the second partial oxidation zone in a reducing atmosphere that includes the second split raw product gas stream from the first partial oxidation zone. By the subject process, there is a reduction in the unconverted carbon produced without any significant loss in efficiency. Further, the life of the cooler for the raw product gas stream is increased.

Electrochemical oxidation of aliphatic hydrocarbons promoted by inorganic radicals. I. OH radicals

Abstract: The OH initiated oxidation of aliphatic hydrocarbons by the simultaneous electrochemical reduction of O2 and of Fe(III) at controlled potential was investigated in the liquid phase over a Fe(III) concentration range 0.5–5 mM. OH radicals were generated by the reaction: Fe(II)+H2O2→Fe(III)+.OH+OH−

Method for wet combustion of organic material

Abstract: The wet method of combusting organic material dispersed in a liquid comprising waste liquor from wood pulping processes in which the organic material is oxidized by contact with air or other oxygenating gases at a temperature ranging between 180° C. and 340° C. and a correspondingly superatmospheric pressure. The combustion of oxygenation is carried out in two steps: namely, a first step in which the organic material is partially oxidized so that the major portion of the organic substances is converted into carbon dioxide and water, and a minor portion is converted to water-soluble low-molecular fatty acids resistant to oxidation; in a second oxidizing step, the residual oxygen-resistant fatty acids are combusted in the presence of a substantial excess of oxygen-enriched air or other molecular-oxygenating gas so as to liberate the total heat of combustion of the organic material and to impart to the resultant gaseous mixture of effluents a molecular oxygen content sufficient to achieve the partial oxidation in the first step.

Process for the production of synthesis gas

Abstract: Process for the production of synthesis gas with an increased H 2 /CO-ratio from normally gaseous hydrocarbons comprising the following steps: a) at least one normally gaseous hydrocarbon is converted into a synthesis gas comprising H 2 and CO by partial oxidation with an oxygen-containing gas; b) at least one normally gaseous hydrocarbon is converted with steam into a gaseous mixture comprising H 2 and CO; c) the gaseous mixture comprising H 2 and CO, formed in step (b) is separated into a CO-containing stream and a H 2 stream; d) the H 2 /CO-ratio of the synthesis gas produced in step (a) is increased by adding at least part of the H 2 stream obtained in step (c) thereto.

Utilization of low grade fuels

Abstract: There is provided a process and reaction system for the highly efficient utilization of solid fuels with a low content of organic matter, which may have a high sulfur content and a high mineral carbonate content. Carbonate decomposition is minimized and most of the sulfur is removed from the resulting ash which can be used to make construction materials. The process is effected in 3 stages, the first two of these comprising fluidized bed operation. In the first stage pyrolysis, gasification and only partial oxidation of organic matter takes place, in the second stage combustion of residual carbon is effected in the presence of an excess of air. In the third stage the streams of combustible material coming from the first two stages are combusted. Among suitable dilute solid fuels there are low grade oil shales. The operating conditions have to be adjusted according to the nature of the solid fuel type.

Partial oxidation of methane by nitrous oxide over Bi2O3–SnO2

Abstract: On a Bi2O3–SnO2 catalyst N2O partially oxidizes methane to formaldehyde with a selectivity of 95–84% at 1.7–2.7% conversion at 550 °C.

Production of synthesis gas using an I.C. engine

Abstract: Synthesis gas comprising essentially carbon monoxide and hydrogen is produced by introducing hydrocarbon fuel 16, oxygen/steam 15 and optionally hot water 17 to an internal combustion engine 11. The amounts of steam, oxygen and water are arranged so that partial oxidation of the fuel takes place. The engine simultaneously produces useful work that may be used to generate electric power and synthesis gas with a minimum of low grade heat being produced. A portion of the carbon monoxide produced is reacted with steam in a shift reactor 14 to produce CO2 and hydrogen.