Showing papers on "Dehydrogenation published in 1971"

Endothermic fuels for hypersonic vehicles

Abstract: The use of hydrocarbon fuels for hypersonic vehicles will require increasing utilization of the fuel as vehicle speed increases. In order to achieve maximum heat sinks endothermic reactions must be employed to augment fuel enthalpy. Various reactions, such as thermal cracking, depolymerization, dehydrogenation, and dehydrocyclization, can be used and have been studied. Of these, the catalytic dehydrogenation of naphthenes shows the most promise for practical application. The dehydrogenation of MCH over a Pt/AJfoOa catalyst can approximately double the 1000 Btu/lb available from fuel enthalpy. This should provide cooling sufficient to allow flight into the range of Mach 10 at optimum altitude. However, the application of cooling to the various portions of the aircraft will present formidable problems. Factors that are important in this consideration such as thermal stability, reaction rate, reactor weight and volume, heat transfer, pressure drop, combustion characteristics, and the mating of the cooling system to the aircraft are discussed.

Preparation of aromatics

Abstract: A process for the preparation of aromatic compounds is set forth which involves contacting a feed consisting essentially of C2-C4 paraffins and/or olefins with a crystalline aluminosilicate of the ZSM-5 type and recovering the aromatics produced. The described process can be carried out in the absence of a hydrogenation/dehydrogenation component and in the absence of added hydrogen.

Stereochemistry of Dehydrogenation by D-Galactose Oxidase

Abstract: The stereochemistry of dehydrogenation of the primary carbinol group of D-galactose by D-galactose oxidase has been determined. Using D-galactose-6-d and methyl β-D-galactopyranoside-6-d, it has been established that the reaction involves removal of the pro-S 6-hydrogen atom. This conclusion is based on product analysis, and on the relative impact of the deuterium isotope effect on oxidation rates of substrates having different R:S deuteration patterns. The absolute configurations at C-6 of these substrates have been determined by selective chemical transformations to products of known configuration. The rotational conformation of the 6-carbinol group of D-galactose and its possible relationship to the specificity of the enzyme are discussed, as well as the stereochemistry of reductive deuteration of aldehydo sugar derivatives.

Production of gasoline components including 2-methyl-2-methoxypropane

Abstract: Process of producing 2-methyl-2-methoxypropane and alkylate from a stream of mixed C4''s wherein said stream is fed to a dehydrogenation unit, the dehydrogenation unit effluent is fed to an etherification unit along with methanol which selectively reacts with the isobutene present to form 2-methyl-2methoxypropane. The unreacted C4''s are sent to an alkylation unit where the olefins present react with isobutane to form alkylate. The unreacted products of the process possess a higher overall octane rating than the alkylate which is normally produced.

Catalytic process for upgrading cracked gasolines

Abstract: A PROCESS IS DISCLOSED FOR UPGRADING CATALYTICALLY CRACKED GASOLINE WHICH INVOLVES FRACTIONATING A CATALYTICALLY CRACKED GASOLINE INTO A C6- OVERHEAD AND A C7+ BOTTOM FRACTION AND CONTACTING THE C7+ BOTTOM FRACTION WITH A ZSM-5 TYPE ZEOLITE. THE LIQUID PRODUCT OBTAINED FROM CONTACTING THE C7+ BOTTOM FRACTION WITH THE ZSM-5 TYPE ZEOLITE IS THEREAFTER BLENDED WITH THE ORIGINAL C6- FRACTION TO GIVE A FINAL GASOLINE OF INCREASED OCTANE NUMBER. THE REACTION CAN BE CARRIED OUT IN THE ABSENCE OF HYDROGEN AND IN THE ABSENCE OF A HYDROGENATION/DEHYDROGENATION COMPONENT ON THE ZEOLITES.

Hydrocarbon conversion with platinum second metal catalysts in proportions which form ordered alloys

Abstract: A HYDROCARBON CONVERSION CATALYST OF 0.01-10% WT. METAL ON A REFRACTORY SUPPORT CONTAINS PLATINUM AND A SECOND METAL WHICH FORMS A SOLID SOLUTION WITH PT, THE ATOMIC AMOUNTS OF EACH BEING EQUIVALENT TO AMOUNTS FORMING ORDERED ALLOY STRUCTURES. THE SECOND METAL MAY BE CO, NI, FE, CU, SN, PD (PARTICULARLY THESE SIX), IR, RH, AG, AU, BI, HG, SB, PD OR CD AND PREFERABLY THERE IS AT LEAST 45 ATOMIC PERCENT PT. THE CATALYSTS MAY BE PREPARED BY KNOWN IMPREGNATION OR ION-EXCHANGE TECHNIQUES AND ARE PREFERABLY REDUCED BEFORE USE AT 250-600*C. THE PREFERRED USE IS DEHYDROCYCLISATION OR DEHYDROGENATION OF C3-C25 HYDROCARBONS, PARTICULARLY THE CATALYTIC REFORMING OF 15-204*C. BOILING RANGE PETROLEUM FRACTIONS. D R A W I N G

Oxidative dehydrogenation catalyst

Abstract: Ferrous metal/tin/phosphorus/alkali metal/oxygen-containing oxidative dehydrogenation catalysts are improved by including a small amount of lead; higher yields and higher gas phase selectivities to dehydrogenated products in the oxidative dehydrogenation process are achieved by these novel lead-containing catalysts.

Dehydration and Dehydrogenation of Alcohols over Acid-Base Bifunctional Catalysts

Abstract: Alkaline earth silicates having both acidic and basic sites can be considered as acid-base bifunctional catalysts. Dehydration and dehydrogenation of alcohols over these catalysts were carried out. Correlation between the selectivity and acid-base properties of alcohols and the catalysts was studied. It was found that acid-base properties of both the catalysts and the alcohols were cooperative in determining the selectivity of reaction.

Dehydrogenation method and multicomponent catalytic composite for usetherein

Abstract: DEHYDROGENATABLE HYDROCARBONS ARE DEHYDROGENATED BY CONTACTING THEM AT DEHYDROGENATION COIDITIONS WITH A CATALYTIC COMPOSITE, COMPRISING A COMBINATION OF CATALYTICALLY EFFECTIVE AMOUNTS OF A PLATINUM GROUP COMPONENT, A TIN COMPONENT AND A GERMANIUM COMPONENT WITH A POROUS CARRIER MATERIAL. A SPECIFIC EXAMPLE OF THE CATALYTIC COMPOSITE DISCLOSED HEREIN IS A COMBINATION OF A PLATINUM GROUP COMPONENT, A TINCOMPONENT, A GERMANIUM CONPONENT AND AN ALKALI OR ALKALINEEARTH COMPONENT WITH A POROUS CARRIER MATERIAL WHEREIN SUBSTANTIALLY ALL OF THE PLATINUM GROUP COMPONENT IS PRESENT AS THE ELEMENTAL METAL AND SUBSTANTIALLY ALL OF THE GERMANIUM COMPONENT IS PRESENT IN AN OXIDATION STATE ABOVE THE ELEMENTAL METAL, WHEREIN THE COMPOSITE CONTAINS ABOUT 0.01 TO ABOUT 2 WT. PERCENT OF PLATINUM GROUP METAL, ABOUT 0.01 TO ABOUT 5 WT. PERSENT TIN, ABOUT 0.01 TO ABOUT 5 WT. PERCENT GERMANIUM AND ABOUT 0.01 TO ABOUT 5 WT. PERCENT ALKALY OR ALKALINE EARTH METAL.

Sequential 11α‐hydroxylation and 1‐dehydrogenation of 16α‐hydroxycortexolone

Abstract: Two-step microbial transformation of 16α-hydroxycortexolone to its 1-dehydro-11α-hydroxy derivative, without isolating an intermediate, was achieved with an overall yield of 72% of product at a steroid substrate concentration of 3 mg/ml. The process included formation of the cycloborate complex of the substrate, hydroxylation of the borate complex with a suspension of Aspergillus ochraceus mycelium in phosphate buffer, and dehydrogenation of the 11α-hydroxylated intermediate with acetone-dried Arthrobacter simplex cells. The desired product was then obtained by breaking the resultant borate complex through acidification.

The Dehydrogenation of Butyl Alcohols by the Molten-metal Catalysts

Abstract: In order to investigate the catalytic activity of molten metals, the dehydrogenation reactions of n-butyl alcohol, iso-butyl alcohol, and sec-butyl alcohol were carried out in the presence of molten zinc and molten indium (molten gallium was also used for the dehydrogenation of iso-butyl alcohol). According to the experimental results, all of these molten metals showed persistent catalytic activities and high selectivities for all the test reactions, and the decreasing order of the reactivity of the butyl alcohol isomers was found to be sec-butyl alcohol > iso-butyl alcohol > n-butyl alcohol. Among the three molten metals, i.e. Zn, Ga, and In, the activity and the selectivity of the molten zinc catalyst was outstandingly high. Further, kinetic analyses of the data showed that a compensation effect exists between the apparent activaiton energy, Ea, and the logarithmic frequency factor, logA.

Catalytic Oxidation over Molecular Sieves Ion-exchanged with Transition Metal Ions. IV. The Oxidative Dehydrogenation of Cyclohexane

Abstract: The oxidative dehydrogenation of cyclohexane over molecular sieves ion-exchanged with cupric ion (Cu(II)–Y) was investigated by means of an ordinary flow reactor with a reactant gas composed of 1.0% cyclohexane, 50% oxygen, and 49% nitrogen. The reaction was studied at temperatures between 210–350°C; here, carbon dioxide and benzene were the main products. The Cu(II)–Y was found to be a very active catalyst for the oxidation of cyclohexane as well as for that of olefins, in comparison with an ordinary cupric oxide catalyst supported on silica gel; the selectivity for benzene formation was as high as 80% below 10% conversion. Both products were found to be formed in competitive reactions. The catalytic activities were also studied on molecular sieves ion-exchanged with other transition metal ions, such as palladium (II), silver (I), and zinc (II). The relations between the catalytic activities and the heats of formation of the corresponding metal oxides per g-atom oxygen were examined; volcano-shaped corre...

Oxidative dehydrogenation in the presence of crystalline,provoskite type manganese compounds

Abstract: PROCESS FOR THE OXIDATIVE DEHYDROGENATION OF DEHYDROGENATABLE ORGANIC COMPOUNDS BY HEATING THE COMPOUNDS WITH OXYGEN (AND OPTIONALLY HALOGEN) IN THE PRESENCE OF A SOLID CRYSTALLINE CATALYST CONTAINING MANGANESE AND AT LEAST TWO OTHER METALS, ONE OF WHICH IS A LIGHT METAL HAVING AN OXIDATION STATE OF 1+ OR 2+. MANGANESE COMPOUNDS OF THE PEROVSKITE STRUCTURE ARE PREFERRED CATALYSTS.

MANUFACTURE OF .alpha.-.beta.-UNSATURATED CARBONYL COMPOUNDS

Abstract: A PROCESS FOR THE MANUFACTURE OF A,B-UNSATURATED CARBONYL COMPOUNDS BY CONTACTING THE CORRESPONDIN B,$-UNSATURATED ALCOHOLS WITH A DEHYDROGENATION CATALYST AT TEMPERATURES RANGING FROM 150* TO 600*C. THE REACTION PROCEEDS PARTICUARLY WELL WHEN CARRIED OUT IN THE PRESENCE OF CATALYTIC AMOUNTS OF CERTAIN NUCLEOPHILIC SUBSTANCES.

Hydrocarbon conversion process for the production of olefins and aromatics

Abstract: DISCLOSED IS A PETROLEUM REFINING PROCESS WHICH MAXMIZES PRODUCTION OF AROMATICS AND OLEFINS. PROCESS INCORPORATE HYDROCRACKING, CATALYTIC CRACKING, REFORMING. POLYMERIZATION, DEHYDROGENATION AND EXTRACTION OPERATIONS WITH MAXIMIZED CYCLING OF REFINERY STREAMS TO THE REFORMING AND DEHYDROGENATION PHASES.

Polymerization of vinyl aromatic compounds

Abstract: A PROCESS FOR THE ANIONIC POLYMERIZATION OF AT LEAST ONE VINYL AROMATIC MONOMER SELECTED FROM STYRENE AND HYDROCARBYL SUBSTITUTED STYRENES COMPRISING POLYMERIZING THE MONOMER IN THE PRESENCE OF A CATALYST COMPRISING A METAL OF GROUP 1-A OF THE PERIODIC TABLE OR A HYDRIDE OR HYDROCARBYL THEREOF CHARACTERIZED IN THAT THE FEEDSTOCK FOR THE POLYMERIZATION IS THE HYDROCARBON EFFLUENT OF A DEHYDROGENATION REACTION COMPRISING AT LEAST 5% BY WEIGHT OF SAID MONOMER AND IN THAT AT LEAT A PROPORTION OF THE HEAT OF POLYMERIZATIOM IS RETAINED IN THE REACTION MIXTURE WHEREBY THE TEMPERATURE OF THE MIXTURE IS CAUSED TO RISE AND IS FOR AT LEAST PART OF THE REACTION TIME IN EXCESS OF 100*C.

Cobalt,iron,phosphorus and oxygen containing oxidatice dehydrogenation catalyst

Abstract: ORGANIC COMPOUNDS ARE DEHYDROGENATED TO COMPOUNDS HAVING A HIGHER DEGREE OF UNSATURATION BY CONTACTING THE FEEDSTOCK IN THE VAPOR PHASSE IN THE PRESENCE OF AN OXYGENCONTAINING GAS WITH A CATALYST CCOMPRISING COBALT IN ASSOCIATION WITH IRON, PHOSPHORUS AND OXYGEN. REPRESENTATIVE OF SUCH CONVERSIONS IS THE OXIDATIVE DEHYDROGENATION OF ISOPENTANCE TO ISOPRENE AND ISOAMYLENES. THE CONVERSION PRODUCTS ARE VALUABLE COMPOUNDS PARTICULARLY USEFUL AS INTERMEDIATES FOR THE PREPARATION OF POLYMERIC MATERIALS SUCH AS SYNTHETIC RUBBERS AND THE LIKE.

Conversion of ethylbenzene to styrene

Abstract: IN A PROCESS FOR THE STEAM DEHYDROGENATION OF ETHYLBENZENE TO STYRENE, THE SELECTIVITY OF THE DEHYDROGENATION REACTION IS IMPROVED BY MAINTAINING THE REACTOR PRODUCTS SETTLER, WHEREIN CONDENSED REACTOR PRODUCTS ARE SEPARATED, AT A PRESSURE LESS THAN ATMOSPHERIC.

Catalyst for oxidative dehydrogenation

Abstract: ORGANIC COMPOUNDS ARE DEHYDROGENATED TO COMPOUNDS HAVING A HIGHER DEGREE OF UNSATURATION BY CONTACTING THE FEEDSTOCK IN THE VAPOR PHASE IN THE PRESENCE OF AN OXYGEN-CONTAINING GAS WITH A CATALYST COMPRISING AT LEAST ONE OF NICKEL, COBALT OR IRON IN ASSOCIATION WITH TIN AND PHOSPHORUS. REPRESENTATIVE OF SUCH CONVERSIONS IS THE OXIDATIVE DEHYDROGENATION OF BUTANE TO BUTENES AND BUTADIENE, ISOPENTANE TO ISOAMYLENES AND ISOPRENE, AND BUTENES TO BUTADIENE. THE CONVERSION PRODUCTS ARE VALUABLE COMPOUNDS PARTICULARLY USEFUL AS INTERMEDIATES FOR THE PREPARATION OF POLYMERIC MATERIALS SUCH AS SYNTHETIC RUBBERS AND THE LIKE.

Tin-phoshorus catalyzed oxidative dehydrogenation

Abstract: THE ACTIVITY OF TIN-PHOSPHORUS OXIDATIVE DEHYDROGENATION CATALYSTS IS SIGNIFICANTLY IMPROVED BY INCLUDING A HEATVOLATILE ACTIVITY-STIMULATING AMMONIUM SALT IN THE CATALYST COMPOSITION PRIOR TO THE CATALYST PARTICLE-FORMING STAGE.