摘要:
A process for the synthesis of aromatic isocyanates by the reduction of aromatic derivatives with carbon monoxide in the presence of catalysts consisting of metal complexes of porphyrins. In one embodiment, the metallic porphyrin is synthesized in situ from a porphryin and a metal or a metal derivative.
摘要:
A process for the manufacture of aromatic isocyanates by carbonylation of nitro derivatives comprising carrying out the reaction in the presence of supported catalysts containing as the active phase particles or an oxide of a precious metal of Group VIII and of a metal selected from Group V.sub.B, VI.sub.B, and VIII of the Periodic Table; the precursor of the active phase being a heteropolymetallic complex and, more particularly, a mixed bimetallic cluster.
摘要:
A process for the manufacture of polyurethanes by direct reaction in the liquid phase, comprising reacting, in the presence of a catalyst, carbon monoxide with a nitrated hydroxy-aromatic derivative of the formula:HO--Ar--NO.sub.2wherein Ar represents the aromatic radical: ##STR1## with the nitro and hydroxyl functional groups being in the para or meta positions with respect to each other, and R representing hydrogen or halogen atoms, or an alkyl group containing from 1 to 10 carbon atoms.
摘要:
Process for the preparation of 2-benzoxazolone and derivatives by the reaction, in the liquid phase, at a temperature from 100.degree. to 500.degree. C. and a pressure from 20 to 500 bars, of an ortho-nitrophenol of the formula: ##STR1## in which R represents a hydrogen or halogen atom, an alkyl group containing from 1 to 10 carbon atoms or an alkoxy group OR' in which R' represents an alkyl group containing from 1 to 10 carbon atoms, and carbon monoxide under pressure, characterized in that the process is carried out in the presence ofa. a supported catalyst formed by the association of a noble metal of Group VIII and a second transition metal selected from Groups, V.sub.b, VI.sub.b or VIII of the Periodic Classification, in the metallic or oxide form, andb. a nitrogenous heteroaromatic base; the process may be carried out in the presence of a solvent.
摘要:
Silver catalysts for vapor phase synthesis of ethylene oxide by reacting oxygen or gaseous mixtures containing same with ethylene, characterized by the use as support of a porous material having a specific surface area of less than 10 sq. m/g, a total volume of porosity of between 0.1 and 0.6 cm.sup.3 /g and a bimodal distribution of the porosity.
摘要:
A process for manufacturing silver catalysts deposited on a porous refractory support, comprising impregnating a refractory support with a portion of the silver required for the catalyst by immersing the support in a practically anhydrous solution of an organic carboxylic acid salt of silver in an organic liquid which complexes the silver ions, removing excess organic liquid from the support without causing the deposition of metallic silver thereon; depositing the remainder of the silver and at least one promoter selected from cesium, rubidium, or potassium on the support modified by the first silver deposit by immersing said modified support in a practically anhydrous solution of an organic carboxylic acid salt of silver in an organic liquid which complexes the silver ions, said organic liquid containing in the solubilized state, a salt of at least one of the promoters, before transformation of the silver deposited into metallic silver.
摘要:
The invention relates to the manufacture of chlorofluoroethanes of formula CF.sub.3 --CHF.sub.x Cl.sub.2-x, where x is equal to 0 or 1, by catalytic hydrogenation of a perhaloethane of formula CF.sub.3 --CF.sub.x Cl.sub.3-x.The use of an iridium-based catalyst deposited on a support enables the selectivity to be improved.
摘要翻译:本发明涉及通过式CF 3 -CF x Cl 3-x的全卤代乙烷的催化氢化来制备式CF 3 -CHF x Cl 2-x的氯氟乙烷,其中x等于0或1。 沉积在载体上的铱基催化剂的使用使得能够提高选择性。
摘要:
The invention concerns a process for the preparation of 2-(4-aminophenyl)-5-aminobenzimidazole and substituted derivatives by catalytic cycloreduction of starting material N-(4-nitrobenzoyl)-2,4-dinitroaniline or a substituted derivative by hydrogen gas. According to the invention, the starting material is treated in suspension in an aqueous solution of hydrochloric or phosphoric acid, the content (C) of starting material in said suspension ranging from 0.15 to 1.5 mole per liter and the molar ratio (A): acid/starting material being from 2 to 20. The process is carried out at a hydrogen pressure from 5 to 100 bars and a temperature (T) from 20.degree. to 150.degree. C. selected so that the product T.times.A.times.C is equal to or greater than 25. There is thereby obtained a product of excellent purity with very good yields.
摘要:
Substantially increased yields of pure-grade 8-hydroxyquinoline are obtained by gradual addition of a solution of o-nitrophenol in acrolein or in an allylidene acetal or diester, to an aqueous acid solution of o-aminophenol. 8-hydroxyquinoline is an article of commerce having known uses.
摘要:
The invention relates to hydrogenolysis of a chlorofluoroethane XYClC--CClX'Y' or of a chlorofluoroethylene XClC.dbd.CX'Y (where at least one of the symbols X, X', Y and Y' is a fluorine atom and the others are hydrogen or chlorine atoms) which is performed on a mixed catalyst based on copper or silver and on at least one platinum group metal (Ru, Rh, Pd, Os, Ir, Pt), these metals being deposited on a support.Even at low operating temperatures, excellent degrees of conversion and selectivities for fluoroethylenes and/or chlorofluoroethylenes are obtained.