Abstract: Sulphur dioxide and unreacted monomer or mixture of monomers are separated and recovered from the polymer or copolymer slurry obtained by polymerizing acrylonitrile monomer or copolymerizing acrylonitrile monomer and a further ethylenically unsaturated monomer copolymerizable therewith in the presence of a catalytic system comprising sulphur dioxide or a sulphite, by a process comprising the steps of separately removing the sulphur dioxide and the monomer or mixture of monomers from the slurry in two distinct volatilization zones connected in series under decreasing subatmospheric pressures, scrubbing with water the sulphur dioxide vapors removed in the first zone and vapors of unreacted monomer or monomers removed in the second zone, and recycling the two resulting aqueous solutions to the polymerization or copolymerization medium.

Abstract: Ethylene oxide is prepared by oxidation of ethylene on a catalyst obtained by:A. impregnating particles of a subdivided inert support with a decomposable silver salt,B. drying said impregnated particles by heating to a maximum temperature not exceeding 160.degree.C,c. flowing through the dried particles a gaseous stream of superheated steam, the temperature being raised to a selected value from 270.degree. to 350.degree.C,d. gradually replacing the steam by air over a period of at least 1 hour with the temperature being maintained at said selected value, andE. maintaining the particles for at least 30 minutes under the stream of air, with the temperature being maintained at said selected value.

Abstract: An insaturated polyester A of the formula: ##EQU1## wherein n is an integer from 0 to 15, R.sub.11 ##EQU2## is the acid radical of an unsaturated monocarboxylic acid or of a monoester of an unsaturated bicarboxylic acid, R.sub.13 is H or CH.sub.3, and R.sub.10 is an organic radical of a glycol HO-R.sub.10 -OH representated by the formulae: ##SPC1##Wherein:R.sub.1 is chlorine or bromine,R.sub.2 , r.sub.3, r.sub.4, r.sub.5 , r.sub.6, r.sub.7, r.sub.8 are hydrogen or bromine or chlorine,X is a NH radical or oxygen,R.sub.9 is an alkyl or oxyalkyl radical containing 2 to 8 carbon atoms.The solutions in an unsaturated solvent of said polyester A or of mixtures of polyester A with other unsaturated polyesters can harden, giving products of improved mechanical and self-extinguishing properties.

Abstract: The palladium and copper ethylene-oxidation catalysts used in vinyl acetate production are regenerated by a process including a galvanic displacement of the metals from solution and their reconversion to halides.

Abstract: Silver-based catalysts suitable for the production of ethylene oxide are prepared by impregnating a granular support with a decomposable silver salt, drying the impregnated products, and finally heat-treating the dried product at a high temperature, in a gaseous atmosphere containing at least 1 % by volume of carbon dioxide.

Abstract: A method of polymerizing acrylonitrile monomer or copolymerizing a mixture of acrylonitrile monomer and further ethylenically unsaturated monomer copolymerizable therewith which comprises contacting in an aqueous medium the monomer of mixture of monomers with a catalytic system comprising hydrogen perioxide, a water-soluble salt of a hydroxylamine mono- or disulfonic acid and a water-soluble salt of a variable valence metal, such as a ferrous salt.

Abstract: Process for the purification of titanium tetrachloride, in which the said titanium tetrachloride is brought into contact with a purifying agent consisting of an inert support in granular form on which metallic sodium or other reducing metal has been deposited in sub-divided form, the said contact taking place either on crude liquid titanium tetrachloride with subsequent distillation to recover the purified titanium tetrachloride or on crude vaporised titanium tetrachloride with subsequent condensation to recover the purified titanium tetrachloride.

Abstract: A process for the production of ethylene glycol ethers by reacting ethylene oxide with monofunctional aliphatic alcohols, which comprisesReacting a monofunctional aliphatic alcohol and ethylene oxide in a first reaction stage in a molar ratio of from about 3:1 to 20:1;Separating excess alcohol from the ethylene glycol ethers obtained as the reaction products in the first stage;Reacting the ethylene glycol ethers with ethylene oxide in a molar ratio of from about 1:1 to 10:1 and with monoethylene glycol ether in a second reaction stage;Separating the monoethylene glycol ether and the diethylene glycol ether from the reaction products of the second stage, maintaining a weight ratio of the discharged fraction to the recycled fraction of from about 0.5:1 to 5:1.The reaction is carried out under abiabatic conditions in the first stage and under isothermal conditions in the second stage.