摘要:
Process for producing substituted or unsubstituted naphthalic acids and acid anhydrides thereof by oxidation of corresponding acenaphthenes whose naphthalene nucleus may have one or two substituents from the group consisting of halogens, sulfonic acid groups, sulfonate groups, and nitro. The oxidation is performed at 30.degree.-150.degree. C. using molecular oxygen in the presence of (1) at least one heavy metal compound, such as cobalt acetate or manganese acetate, in an amount of 0.005-0.3 mole per mole of said acenaphthenes or a mixture of heavy metal compounds in that amount and a bromine compound in the range of 5.times.10.sup.-5 to 2.times.10.sup.-1 mole/liter of reaction solution as a catalyst and (2) at least one accelerator selected from the group consisting of lower fatty acid anhydrides, ketones and aldehydes, whereby side reactions such as condensation can be suppressed to a satisfactory extent, thereby leading to an improvement in yield of final product. A subsequent treatment of the oxidation product obtained by this process with peroxides, hypohalogenates, or molecular oxygen results in a higher yield.
摘要:
An improved catalyst structure for use in catalytic processes, consisting of a powdered catalyst, carrier, and metal fiber thoroughly mixed to assure a permanent uniform distribution of the metal fiber, the catalyst-metal fiber mixture then pressed into any desired shape for its intended use. The permanent uniform dispersion of metal fibers results in a catalyst structure having increased thermal conductivity and more uniform porosity, the improved heat transfer characteristics increasing selectivity and minimizing temperature gradients in the catalytic structure thereby assuring constant reactor temperature and imparting stability, improved yield and temperature control in highly exothermic and endothermic catalytic reactions.
摘要:
The novel compound 4-dimethylaminopyridinium chlorochromate has been found to be an effective oxidizing agent for converting alcohols to their respective aldehydes or ketones, especially for the selective conversion of allylic and benzylic alchols to their corresponding aldehydes and ketones.
摘要:
The reactor is traversed by a central tube with an essentially radial circulation of the gases or other fluids. Said cylindrical part of the solids bed is surmounted by a substantially hemispherical reaction zone permeable to said gases or other fluids. The hemispherical part of the reactive zone is comprised between two substantially hemispherical caps one of which surmounts the central tube and the other bounds the upper periphery of this zone with the pressure drop undergone by the gases or other fluids passing through the hemispherical zone being greater than that undergone by the gases or other fluids passing through the cylindrical zone and therefore the perforations of the hemispherical part of the central tube are calculated to compensate for this difference and equalize the flow of gases or other fluids in the whole of the solids mass.
摘要:
A process for the preparation of citric acid which comprises contacting an unsaturated compound selected from 3-methylene-1,5-pentanediol and its esters with a nitric acid solution in an amount of 2 to 50 mols of nitric acid feed per mol of unsaturated compound feed, and at least 0.005 mol percent nitrogen dioxide based on nitric acid, at a temperature between -10.degree. and 120.degree. C., to thereby oxidize said unsaturated compound to citric acid. Preferably the contacting of the unsaturated compound so as to synthesize citric acid is carried out in the absence of any substantial amount of vanadium as the presence of vanadium catalysts has been found to effectively prevent the recovery of good yields of citric acid from the process.The citric acid synthesis preferably is carried out by an overall process wherein isobutene is reacted with two mols of formaldehyde to produce 3-methylene-1,5-pentanediol, which is then converted to citric acid by reaction with nitrogen dioxide/nitric acid.Citramalic production from 3-methyl-3-buten-1-ol is also disclosed.
摘要:
THE OXIDATION OF ORGANIC COMPOUNDS USING A NITRO OR NITROSO AROMATIC AS AN OXIDANT IN THE PRESENCE OF A NON-AQUEOUS REACTION MEDIUM CONTAINING A RUTHENIUM OR RHENIUM CATALYST AND ALKALINE CONDITIONS IS DISCLOSED. PREFERABLY, THE CATALYTICALLY ACTIVE METAL IS IN COMPLEX ASSOCIATION WITH A BIPHYLLIC LIGAND. EXAMPLES OF OXIDIZABLE SUBSTRATES ARE ARYL AND ALKYL SUBSTITUTED AROMATICS; CONDENSED RING AROMATICS; PHENOLS; OLEFINS; ALKYNES; SATURATED HYDROCARBYL ALCOHOLS, KETONES, ALDEHYDES, HALIDES, ETHERS, AMINES AND CARBOXYLIC ACIDS AND HALIDES AND ALKYL ESTERS THEREOF; AND HETEROCYCLIC AMINES. THE OXIDATION IS PERFORMED UNDER RELATIVELY MILD CONDITIONS INCLUDING TEMPERATURES FROM 50* TO 350* C. AND PRESSURES FROM 0.1 TO 1000 ATMOSPHERES.