Abstract:
The present invention relates to a water-absorbing material obtainable by a process comprising the steps of A) treating a particulate, non-surface-crosslinked, water-absorbing polymer with a mixture comprising an aqueous solvent and at least one salt of a transition metal and B) irradiating the polymer treated according to A) with UV radiation, to a process for its production and to articles comprising the water-absorbing material.
Abstract:
The invention relates to the use of a gas or liquid spraying curtain, which is produced by spraying non-combustible gases or liquids, for diluting and/or flushing out clouds of combustible gases, the density of which does not exceed the density of air, from enclosed spaces having one or a plurality of outer openings, and to a method for diluting and/or flushing out clouds of combustible gases, the density of which does not exceed the density of air, from enclosed spaces having one or a plurality of outer openings, characterised in that a gas or liquid spraying curtain is produced by spraying non-combustible gases or liquids at at least one outer opening, which curtain dilutes the cloud of combustible gases situated in the enclosed space and carries it in the direction of the at least one outer opening and thus flushes it out.
Abstract:
The invention describes a method for separating trioxane from a supply flow I of formaldehyde, trioxane, and water, wherein a) a supply flow I containing formaldehyde as the main component and trioxane and water as the secondary components, is provided, b) the supply flow, a return flow V, and a return flow VII containing formaldehyde as the main component and water and trioxane as the secondary components, are fed into a first distillation step and are distilled at a pressure of 0.1 to 2.5 bars, wherein a flow II containing formaldehyde as the main component and water as the secondary component, and a flow III containing trioxane as the main component and water and formaldehyde as the secondary components, and a flow X containing water, trioxane and formaldehyde, are obtained, c) the flow III, optionally after separating low boilers from the flow III in a low boiler separating step, is distilled in a second distillation step at a pressure of 0.2 to 17.5 bars, wherein the pressure in the second distillation step is higher than the pressure in the first distillation step by 0.1 to 15 bars, wherein a flow IV, substantially consisting of trioxane, and the return flow V containing trioxane as the main component and water and formaldehyde as the secondary components, are obtained, d) the flow IV is purified in at least one further trioxane distillation step at a head pressure of 0.5 to 2 bars, wherein purified trioxane is obtained as the lateral removal flow is obtained in the reinforcement part of the column, d) the flow X, and optionally a flow IX containing water as the main component, are fed into a third distillation step and distilled at a pressure of 1 to 10 bars, wherein a flow VI substantially consisting of water, and a return flow VII containing formaldehyde as the main component and water and trioxane as the secondary component, are obtained.
Abstract:
The invention relates to a method for removing formic acid from a mixture that contains formaldehyde, trioxane, water and formic acid, by distillation. According to said method, at least one tertiary amine and/or an imine or a mixture thereof capable of deprotonation and conversion to a salt is added, prior to or during distillation, to the mixture in a catalytic amount or in an amount sufficient to form the salt with the entire amount of formic acid, and the formic acid/amine salt is removed in a liquid phase in the distillation sump.
Abstract:
La presente invención se refiere a un método para la producción de 6-clorodibenzo[d, f] [1,3,2]dioxafosfepina (I) (ver Fórmula) en el cual se hace reaccionar 2,2´-dihidroxibifenilo con PCl3 en presencia de una cantidad catalítica de una sal ácida de una base nitrogenada, la reacción teniendo lugar en ausencia de solventes orgánicos externos.
Abstract:
The present invention relates to a method for producing 6-chlorodibenzo [d,f] [1,3,2]dioxaphosphepin (I) in which 2,2'-dihydroxybiphenyl is reacted with PCl3 in the presence of a catalytic quantity of an acid salt of a nitrogenous base, the reaction taking place in the absence of external organic solvents.
Abstract:
Procedimiento para la preparación de soluciones de compuestos orgánicos, polimerizables por radicales libres, sensibles a la radiación, en el cual a) un primer compuesto de partida que presenta un grupo haluro ácido, y b) un segundo compuesto de partida que presenta un grupo hidroxilo de alcohol, son esterificados entre sí en un solvente o en una mezcla de solventes; y en el cual el solvente son una o varias cetonas con un punto de ebullición por debajo de 150 °C a presión atmosférica (1 bar) o la mezcla de solventes está compuesta por estas cetonas en al menos el 50 % en peso respecto de la cantidad de solventes; y uno de los dos compuestos de partida presenta al menos un grupo sensible a la radiación y el otro de los dos compuesto de partida presenta al menos un grupo etilénicamente insaturado, polimerizable por radicales libres, en cuyo caso el compuesto orgánico, polimerizable por radicales libres, sensible a la radiación, es un fotoiniciador polimerizable que puede incorporarse a la cadena polimérica de los copolímeros mediante copolimerización por radicales libres, realizándose la esterificación en presencia de al menos una amina orgánica terciaria y añadiéndose después de la reacción agua en una cantidad para que se forme una solución saturada del haluro de amonio orgánico en agua y esta solución acuosa saturada se separe de la fase orgánica, midiéndose la cantidad de agua de tal manera que la cantidad necesaria para la formación de una solución saturada no exceda en más del 10 % en peso de la cantidad teóricamente necesaria.