Abstract: The use of silica for controlling the thermal degradation of bicarbonate of an alkaline, alkaline-earth metal or bicarbonate of ammonia with an average particle size less than or equal to 100 &mgr;m is disclosed. The resulting bicarbonate and silica mixtures may be used in cosmetics and detergents, and more particularly in formulae for toothpaste.

Abstract: The aliphatic carboxylic acids, e.g., acetic acid, are selectively prepared, even on an industrial scale, by controlledly oxidizing the corresponding alkanes, e.g., ethane, with a source of oxygen, in the presence of a catalytically effective amount of an advantageously supported heteropolyacid catalyst having the formula (I):[A.sub.a B.sub.b ].sub.f [C.sub.c D.sub.d E.sub.e O.sub.x ].sup.f-(I)in which A is at least one monovalent cation selected from among hydrogen, an alkali metal, or the ammonium ion; B is VO.sup.2 +, VO.sup.3 +, an alkaline earth metal ion, or an ion of a metal of Groups VII A, VIII, I B, IV B and V B of the Periodic Table; C is Mo and/or W; D is phosphorus, arsenic, antimony, silicon, germanium and/or boron; E is vanadium, optionally in combination with at least one metal of Groups V A, VII A and VIII of the Periodic Table or chromium; f=a+.alpha.b wherein .alpha.

Abstract: A process for producing anhydrides by passing a solution of the acid, preferably an organic polyacid, which is to undergo anhydridation over an acidified clay and a process for producing the catalysts therefor.

Abstract: Process for the treatment of a material comprising a polymer, especially a polyamide. The process consists in subjecting the polyamide to hydrolysis in the presence of a hydrolyzing nitrous grouping and transforming the hydrolyzed compounds into diacids. The treatment of a polyamide 6.6 results in the recovery of adipic acid and other diacids corresponding to the participating acid monomer and to the transformation of at least one part of the diamine monomer into diacids.

Abstract: Disclosed herein is a process for the production of acetic acid by the controlled oxidation of ethanol. The process according to the invention comprises the reaction of ethanol with a source of oxygen. The reaction is performed in the presence of a catalyst in which the active stage is vanadium, titanium, and oxygen.

Abstract: The present invention relates to a process for the preparation of carboxylic acids by controlled oxidation of the corresponding alkanes.The process according to the invention consists in reacting the alkane with a source of oxygen, the reaction being performed in the presence of a catalyst in which the active phase is based on vanadium, titanium, molybdenum, phosphorus and oxygen.

Abstract: Branched saturated dinitrile byproducts, e.g. 2-methylglutaronitrile, 2-ethylsuccinonitrile and mixtures thereof, are converted into useful ethylenic nitriles by dehydrocyanating same, in vapor phase, in the presence of an at least partially acidified cation exchange substrate, notably a molecular sieve, clay, acid oxide or lamellar phosphate.

Abstract: Optionally substituted p-aminophenol compounds, easily converted into the N-acylated derivatives thereof, are prepared by hydrogenating the corresponding nitrobenzene, in solution in a saturated aliphatic monocarboxylic acid, notably acetic acid, in the presence of an effective amount of a protonic acid.

Abstract: The present invention relates to novel .alpha.-hydroxyacids of the general formula (I), to the process of preparing them and to the use thereof as intermediates allowing access to homologous lower aldehydes (such as prenal or citral) by oxidative decarboxylation.

Abstract: A process for producing anhydrides by passing a solution of the acid, preferably an organic polyacid, which is to undergo anhydridation over an acidified clay and a process for producing the catalysts therefor.

Abstract: The phenols and phenol ethers are hydroxylated by reaction with hydrogen peroxide in the presence of a catalytically effective amount of a titanozeosilite, advantageously a silicon oxide/titanium oxide MFI zeolite having the general formula:SI.sub.(96-x), Ti.sub.x O.sub.192.

Abstract: The phenols and phenol ethers, e.g., phenol itself, are effectively hydroxylated by reacting hydrogen peroxide therewith, in the presence of a catalytically effective amount of titanium dioxide.

Abstract: The alkyl hydroquinones, e.g., methyl hydroquinone (a useful intermediate in the preparation of the monomer methyl hydroquinone diacetate, itself used for the synthesis of thermotropic polymers), are prepared by reacting (C-alkylating) hydroquinone or a monoether thereof with a lower alkanal, in the vapor phase, with a catalytically effective amount of at least one solid metal oxide.

Abstract: The invention relates to chemical compounds and their use as catalysts in the solvolysis of alkyl halides. The chemical compounds, when dry, have formula (I):(EO.sub.4 M).multidot.(Imp)p (I)wherein E is selected from the group consisting of phosphorus, arsenic, antimony and bismuth, and is preferably phosphorus, and M is a metal or a mixture of metals.Imp corresponds to a basic impregnating compound consisting of alkaline earth metal, or preferably alkali metal, and their mixtures in combination with a counter-anion to ensure electrical neutrality.The coefficient p is between 10.sup.-2 and 1/3.

Abstract: Mono-, di- and triphenols are selectively monomethylated by reaction with para-dimethoxybenzene in the presence of a catalytically effective amount of an acid catalyst.

Abstract: The bis-(N-carboalkoxyanilino)methanes, optionally in the presence of at least one alkyl N-phenylcarbamate, are selectively rearranged into methylenedi(phenylurethane), MDU, in the presence of an effective amount of hydrofluoric acid.

Abstract: Methylenedi(phenylurethane), MDU, is selectively prepared by condensing an alkyl N-phenylcarbamate with a methylenating agent, e.g., formaldehyde or a precursor thereof, in the presence of a catalytically effective amount of the protonic acid, hydrofluoric acid.

Abstract: Phenol/substituted phenols are prepared by directly hydroxylating an aromatic substrate with nitrous oxide, in vapor phase, in the presence of a modified (acidified) ZSM-5 or ZSM-11 zeolite, containing such elements as Ga, Fe, B, In, Cr, Sc, Co, Ni, Be, Zn, Cu, Sb, As or V.

Abstract: Methylhydroquinone (MeHQ) or methyl ether derivative thereof is prepared by contacting paramethoxyphenol or para-dimethoxybenzene with an acid catalyst, preferably a solid acid catalyst, at a temperature ranging from 100.degree. to 300.degree. C.

Abstract: A process for the preparation of halophenols. A halobenzene is brought into contact with nitrous oxide on an acidified zeolite.