摘要:
Process for the preparation of asymmetrically substituted ureas, carbamates, thiocarbamates or substituted isocyanates by reaction of an adduct of isocyanic acid and a tertiary amine with a primary and secondary amine, an alcohol, a thiol or a compound having one or two non-cumulated olefinic double bonds, and a process for the preparation of N-mono- or N,N-disubstituted ureas by reaction of ammonium isocyanate with a primary or secondary amine in a diluent.
摘要:
Process for the preparation of asymmetrically substituted ureas, carbamates, thiocarbamates or substituted isocyanates by reaction of an adduct of isocyanic acid and a tertiary amine with a primary and secondary amine, an alcohol, a thiol or a compound having one or two non-cumulated olefinic double bonds.
摘要:
A process for the preparation of isocyanic acid, characterized in that N,N-disubstituted ureas are decomposed at elevated temperature to a secondary amine of lower volatility and to isocyanic acid, which is drawn off at the top.
摘要:
Process for the removal of isocyanic acid from a gaseous mixture of isocyanic acid and ammonia by introducing a tertiary amine or ether at 250.degree. to 600.degree. C. The gaseous reaction mixture is passed into an inert diluent and cooled, to condense an adduct of isocyanic acid and tertiary amine or ether, and the ammonia being removed as a gas.
摘要:
Process for the removal of isocyanic acid from a gaseous mixture of isocyanic acid and ammonia by introducing a tertiary amine or ether at 250.degree. to 600.degree. C. The gaseous reaction mixture is passed into an inert diluent and cooled, to condense an adduct of isocyanic acid and tertiary amine or ether, and the ammonia being removed as a gas.
摘要:
An apparatus and process for defined comminution of polymer gels, wherein the apparatus includes a static cutting element in the form of a cutting screen. The cutting element is optionally supported, and has pretensioned wires, rods, fibers, wovens, stencils or profiles. Optionally, a dynamic cutting element is provided for shortening the gel strands or particles obtained by means of the static cutting unit. Also, a feed unit is provided for feeding the polymer gel to the static cutting element in a clamped-in, shape-stable state. The feeding of the gel is effected batchwise or continuously.
摘要:
A process for preparing cyanuric acid by cooling an isocyanuric acid/ammonia gas mixture having a temperature of 300.degree. to 480.degree. C. to 200.degree.-300.degree. C., whereupon cyanuric acid is separated off and isolated at this temperature in an apparatus suitable for separating solids from gases, and unreacted isocyanuric acid/ammonia gas mixture is recycled or further processed.
摘要:
An apparatus and process for defined comminution of polymer gels, wherein the apparatus includes a static cutting element in the form of a cutting screen. The cutting element is optionally supported, and has pretensioned wires, rods, fibers, wovens, stencils or profiles. Optionally, a dynamic cutting element is provided for shortening the gel strands or particles obtained by means of the static cutting unit. Also, a feed unit is provided for feeding the polymer gel to the static cutting element in a clamped-in, shape-stable state. The feeding of the gel is effected batchwise or continuously.
摘要:
An apparatus and process for defined comminution of polymer gels, wherein the apparatus includes a static cutting element in the form of a cutting screen. The cutting element is optionally supported, and has pretensioned wires, rods, fibers, wovens, stencils or profiles. Optionally, a dynamic cutting element is provided for shortening the gel strands or particles obtained by means of the static cutting unit. Also, a feed unit is provided for feeding the polymer gel to the static cutting element in a clamped-in, shape-stable state. The feeding of the gel is effected batchwise or continuously.