Abstract: To prepare acetic acid and acetic anhydride, methanol and methyl acetate are reacted under anhydrous conditions with carbon monoxide in the presence of a catalyst system containing carbonyl complexes of group VIII noble metals, methyl iodide, an alkali metal acetate or iodide, or quaternary organophosphonium or organoammonium acetate or iodide, The hot carbonylation mixture is decompressed, the evaporated components are fed to a first distillation zone, and the catalyst solution which remains is fed back to the reaction zone. In the first distillation zone, the volatile carbonylation products are subjected to fractional distillation; the low-boiling methyl iodide and methyl acetate pass back into the reaction zone, and the bottom product produced is a mixture of acetic acid and acetic anhydride, which is split into the pure components in a second distillation zone and a third distillation zone.

Abstract: A process for continuously producing an anhydrous methyl acetate/methanol mixture by esterifying acetic acid and methanol in the presence of an acidic esterification catalyst is indicated, which comprises carrying out the esterification in a distillation column having n=20 to 50 distillation trays,a) the acetic acid being fed together with the catalyst to a distillation tray which is at a distance of 0.5 n to 0.8 n from the still bottom,b) feeding 50 to 80% by weight of the total methanol to the still bottom and the remaining methanol to a distillation tray which is 2 to 10 trays above the acetic acid feed tray,c) feeding methanol and acetic acid into the distillation column at a molar ratio of (1.5 to 3):1,d) setting a reflux ratio of (0.75 to 1.5):1,e) taking off the anhydrous methyl acetate/methanol mixture at the top of the column andf) a water/methanol/acetic acid bottom product with the catalyst from the still bottom.

Abstract: A process for inhibiting and destroying peroxides in dialkyl ethers having the general formula R.sub.1 OR.sub.2 in which R.sub.1 and R.sub.2 are alkyl groups having 1 to 6 carbon atoms, which comprises adding, as inhibitor, a quaternary alkyl iodide of the general formula[CH.sub.3 alk.sub.3 P]Ito the dialkyl ethers.

Abstract: A process for removing metallic corrosion products from carbonylation reactions which are carried out under anhydrous conditions and in which methyl acetate and/or methanol and/or dimethyl ether are reacted over a noble metal catalyst system which comprises a noble metal of group VIII of the periodic table of the elements, a co-catalyst, such as iodide or bromide, in particular methyl iodide, and a promoter, such as an organophosphonium or organoammonium salt, and if appropriate a lithium salt, to give acetic acid and/or acetic anhydride is described, the process comprisinga) bringing the reaction solution which is contaminated with metallic corrosion products and contains the catalyst system into contact with an ion exchanger;b) separating this reaction solution which has been brought into contact in this way from the ion exchanger;c) desorbing the promoter adsorbed on the ion exchanger before regeneration with acetic acid and/or acetic anhydride;d) combining the eluate obtained in step c) with the reaction

Abstract: In order to prepare N-acylphosphinothricin diesters, acetals of methyl-(3-oxopropyl)phosphinic acid esters of the formula ##STR1## are reacted in a dipolar aprotic solvent with a carboxylic acid amide and carbon monoxide in the presence of hydrogen gas using a cobalt compound as a catalyst, where the radical R' is alkyl or aryl or aralkyl.

Abstract: In a process for the purification and recovery of a contaminated catalyst solution produced during carbonylation of methanol and/or methyl acetate and/or dimethyl ether and containing carbonyl complexes of rhodium, organic and/or inorganic promoters, undistillable organic impurities and acetic acid, acetic anhydride and ethylidene diacetate, the organic impurities and acetic acid, acetic anhydride and ethylidene diacetate are removed from the contaminatd catalyst solution by extraction at pressures from 35 to 450 bar and temperatures from 0.degree. to 120.degree. C.

Abstract: A process for purifying and recovering the contaminated catalyst solution arising from the carbonylation of methanol, methyl acetate and/or dimethyl ether. The solution contains carbonyl complexes of rhodium, quaternary organophosphorus compounds as organic promoters, undistillable organic impurities, and acetic acid, acetic anhydride and ethylidene diacetate. The carbonyl complex of rhodium together with acetic acid, acetic anhydride and ethylidene diacetate are extracted from the contaminated catalyst solution by using a tri-C.sub.3 - to C.sub.8 -alkylphosphine. The trialkylphosphine phase is separated from the promoter phase and is separated into the volatile constituents acetic acid, acetic anhydride and ethylidene diacetate as well as trialkylphosphine. The rhodium carbonyl complex remaining as the residue and the recovered trialkylphosphine is used for further extraction.

Abstract: In a process for removing the metallic corrosion products from a contaminated catalyst solution produced on carbonylation of methanol and/or methyl acetate and/or dimethyl ether and containing carbonyl complexes of noble metals from group VIII of the Periodic Table of the elements, quaternary organo-phosphorus compounds as organic promoters, metallic corrosion products and acetic acid, acetic anhydride, ethylidene diacetate and, in some cases, undistillable organic compounds, the catalyst solution is treated with water, the noble metal carbonyl complex and the undistillable organic compounds, if present, being precipitated, while the organic promoter and the metallic corrosion products remain in solution; the aqueous phase is separated from the precipitated noble metal carbonyl complex and the organic promoter is extracted from the aqueous phase using C.sub.4 -C.sub.

Abstract: In order to prepare phenylalanine n-propyl ester hydrochloride, phenylalanine hydrochloride is reacted with n-propanol in the molar ration 1: (5 to 20) at temperatures from 80.degree. to 110.degree. C., preferably 85.degree. to 105.degree. C., at pressures from 0.1 to 1.5 bar in the presence of 0.1 to 0.75 mole of HCl/mole of phenylalanine hydrochloride as catalyst and in the presence of water entrainer, a concentration of water entrainer of 20 to 50% by weight being maintained in the reaction mixture.

Abstract: In the process for the preparation of N-acetylphenylalanine by opening the ring of 2-methyl-4-benzylidene-1,3-oxazolin-5-one with water to give 2-acetaminocinnamic acid and subsequently catalytically hydrogenating the latter, both reaction stages are carried out in a mixture of an aliphatic C.sub.3 -ketone to C.sub.10 -ketone or a water-miscible ether and water as the solvent, and the hydrogenation of the 2-acetaminocinnamic acid is carried out at temperatures of 10.degree. to 50.degree. C. and pressures of 1 to 15 bar in the presence of a supported palladium catalyst.

Abstract: Catalyst solution contaminated during the carbonylation of methyl acetate and/or dimethylether.

Abstract: A process for removing by product acetone from reaction mixtures obtained by reacting methyl acetate and/or dimethylether with carbon monoxide at elevated temperatures to obtain acetic anhydride in the presence of a catalyst system consisting essentially of carbonyl complexes of noble metals belonging to group VIII of the Periodic System of the elements, acetic acid, an organophosphorus or organonitrogen compound, and methyl iodide whereby the acetone obtained as a by-product during the reaction is subjected to condensation at temperatures of 50.degree. to 250.degree. C., under pressures of 0.01 to 150 bars and at a molar ratio as above defined for the catalyst system constituent of 1:(25-500):(10-100):(15-150) so as to obtain predominantly higher-boiling secondary products to be distillatively separated in a successive distillation zone together with volatile constituents of the catalyst system.

Abstract: The disclosure relates to a process for separating iodine and its compounds from the carbonlyation products acetic acid, acetic anhydride or ethylidene diacetate obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction. For reducing the quantity of total iodine contaminating the carbonlyation products to less than 20 ppb iodine, the disclosure provides for the carbonylation products to be treated at temperatures of 20.degree. to 250.degree. C. with an alkyl or aryl phosphine or a heterocyclic aromatic nitrogen compound and at least one of the metals copper, silver, zinc or cadmium or their compounds and to be distillatively separated from the iodine thereby fixed in non-volatile form.

Abstract: Catalyst solution contaminated during the carbonylation of methyl acetate and/or dimethylether, containing carbonyl complexes of rhodium, quaternary heterocyclic aromatic nitrogen compounds or quaternary organophosphorus compounds as organic promoters, undistillable organic contaminants, acetic acid, acetic anhydride and ethylidene diacetate, is purified and recovered.

Abstract: In this process for recovering noble metals of group VIII from a contaminated catalyst solution originating from the carbonylation of methyl acetate and/or dimethylether (the catalyst solution containing carbonyl complexes of these noble metals, organic or inorganic promoters, undistillable organic contaminants as well as volatiles) the volatiles are distillatively removed from the catalyst solution and the remaining distillation residue is water-treated, whereby the noble metal/carbonyl-complex is precipitated together with the organic contaminants and is separated from the aqueous phase, while the promotor is dissolved and recovered in conventional manner. The noble metals are then set free in elemental form by subjecting the noble metal/carbonyl-complex separated and contaminated with organic polymers at temperatures of 150.degree. to 300.degree. C. to treatment with an ethyleneglycoldialkylether solvent of the formula R(--OCH.sub.2 --CH.sub.2).sub.

Abstract: The disclosure relates to a process for purifying and recovering a contaminated catalyst solution which is obtained in the carbonylation of methyl acetate and/or dimethylether, the catalyst solution containing carbonyl complexes of noble metals of group VIII of the Periodic System of the elements, quaternary heterocyclic aromatic nitrogen compounds or quaternary organophosphorus compounds as organic promoters, and optionally compounds of carbonyl-yielding common metals as inorganic promoters, undistillable organic contaminants as well as acetic acid, acetic anhydride and ethylidene diacetate.

Abstract: The disclosure relates to a process for separating the catalyst system from reaction mixtures which are obtained by reacting methyl acetate and/or dimethylether with carbon monoxide and optionally hydrogen at elevated temperatures to acetic anhydride and optionally ethylidene diacetate in the presence of a catalyst system consisting of carbonyl complexes of noble metals belonging to group VIII of the Periodic System, acetic acid, an organophosphorus or organonitrogen compound, methyl iodide and optionally compounds of carbonyl-yielding common metals, and which issue from the reaction zone under a pressure of 25 to 150 bars at a temperature of 100.degree. to 250.degree. C. More particularly, the reaction mixture coming from the reaction zone is introduced into a separator heated to 60.degree. to 140.degree. C. and released to a pressure of 0.5 to 3.

Abstract: The disclosure relates to a process for making carboxylic acid halides by reacting an alkyl halide having 1 to 6 carbon atoms or aryl halide with carbon monoxide, optionally in admixture with up to 30 volume % hydrogen, under practically anhydrous conditions at temperatures of 350 to 575 K under pressures of 1 to 300 bars in the presence of a catalyst system containing at least one noble metal belonging to group VIII of the Periodic System of the elements or its compounds, iodine and/or its compounds and optionally an inert organic solvent. To this end, the disclosure provides for use to be made of a catalyst system which additionally contains a compound of the elements belonging to groups I to III of the Periodic System, and acetic acid.

Abstract: The disclosure relates to a process for separating acetone from reaction mixtures originating from the reaction of methyl acetate and/or dimethylether with carbon monoxide and optionally hydrogen in the presence of a catalyst system consisting of carbonyl complexes of noble metals of group VIII of the Periodic System of the elements, acetic acid, an organophosphorus or organonitrogen compound, methyl iodide and optionally carbonyl-yielding compounds of common metals.

Abstract: The disclosure relates to a process for purifying and recovering a contaminated catalyst solution which is obtained in the carbonylation of methyl acetate and/or dimethylether, the catalyst solution containing carbonyl complexes of noble metals of group VIII of the Periodic System of the elements, quaternary heterocyclic aromatic nitrogen compounds or quaternary organophosphorus compounds as organic promoters, undistillable organic contaminants as well as acetic acid, acetic anhydride and ethylidene diacetate.