Abstract: A method for depleting halide ions from liquid ammonia, which comprises bringing the liquid ammonia into contact with a strongly basic ion exchanger, where the basic structure of the strongly basic ion exchanger is a covalently crosslinked polymer matrix and the content of ammonia in the liquid ammonia is more than 98% by weight.

Abstract: The present invention relates to a method for depleting halide ions from liquid ammonia, wherein the liquid ammonia is brought into contact with a strongly basic ion exchanger, where the basic structure of the strongly basic ion exchanger is a covalently crosslinked polymer matrix. Furthermore, the present invention relates to the use of an ammonia obtainable according to the invention as starting material in the production of amines.

Abstract: The present invention relates to a process for working up triethylenediamine (TEDA) in which TEDA is vaporized and the gaseous TEDA is introduced into a solvent, subsequently crystallized and separated off from this and the mother liquor formed is extracted with an extractant, wherein the raffinate phase obtained after the extraction stage is worked up further by adsorption in which extractant and/or by-products and intermediates present in the raffinate phase are removed therefrom.

Abstract: Processes comprising: providing an alkanolic reaction mixture, the alkanolic reaction mixture comprising: at least one alkoxycarbonylaminotriazine; at least one carbonic ester; at least one C1-C13-alkanol, which alkanol may further comprise up to two ether-bound oxygen atoms and may further comprise a substituent selected from the group consisting of C1-C4-alkyls and hydroxyls; and at least one alkali metal alkoxide or alkaline earth metal alkoxide; and subjecting the alkanolic reaction mixture to extraction with a polar extractant such that at least a portion of polar/ionic components present in the reaction mixture are removed, wherein the polar extractant is less than entirely miscible with an organic phase of the reaction mixture, to form an alkanolic phase comprising the at least one alkoxycarbonylaminotriazine and a polar phase comprising the polar extractant and the portion of polar/ionic components; and wherein the extraction is carried out with one or more selected from the group consisting of mixer/

Abstract: Process for recovering (chloro)hydrocarbon-free hydrogen chloride and phosgene-free (chloro)hydrocarbons from a hydrogen chloride stream comprising (chloro)hydrocarbons and phosgene, which comprises i) in a first step, connecting a first adsorber and a second adsorber in series and passing the fresh hydrogen chloride stream comprising phosgene and (chloro)hydrocarbons firstly through the first adsorber and subsequently through the second adsorber until essentially no more (chloro)hydrocarbon is adsorbed by the first adsorber, ii) in a second step, passing the fresh hydrogen chloride stream through the second adsorber while the first adsorber is regenerated, with essentially phosgene-free (chloro)hydrocarbon being obtained in the regeneration, iii) in a third step, passing the fresh hydrogen chloride steam firstly through the second adsorber and subsequently through the regenerated first adsorber until essentially no more (chloro)hydrocarbon is adsorbed by the second adsorber, iv) in a fourth step, passing

Abstract: The invention relates to a process for preparing free-flowing, pulverulent alkoxycarbonylaminotriazine from an alkanolic reaction mixture which is obtained in the preparation of alkoxycarbonylaminotriazines and comprises at least one alkoxycarbonylaminotriazine, at least one cyclic and/or acyclic carbonic ester, at least one C1-C13-alkanol which optionally comprises one or two oxygen atoms in the form of ether bonds and is optionally substituted by C1-C4-alkyl and/or hydroxyl, and also at least one alkali metal or alkaline earth metal alkoxide, with or without melamine and with or without catalyst, by atomizing and drying the reaction mixture in a spray drier.

Abstract: Process for the work-up of a mixture comprising ionic liquids and a further substance, wherein the substance present is separated off by means of adsorptive separation processes.

Abstract: The present invention relates to a process for preparing TEDA solutions comprising a solvent selected from the group consisting of polyhydric alcohols and ethers of polyhydric alcohols. The process comprises passing gaseous TEDA into the solvent and subsequently treating the solutions with one or more suitable adsorbents. This gives solutions which have only low color numbers and are color-stable on storage. The solutions can be used as such in preferred applications of TEDA, preferably polyurethane production.

Abstract: The invention relates to the reduction of the content of MEHQ (methoxyhydroquinone) of acrylic acid or its salts by means of continuous adsorption on activated carbon. In particular, MEHQ is removed from partly or fully neutralized acrylic acid.

Abstract: In a process for preparing polytetrahydrofuran having terminal OH groups (PTHF) from the corresponding polytetramethylene ether having acyloxy end groups by transesterification with alcohols in the presence of a sodium-containing catalyst followed by passing the alcoholic PTHF solution in the presence of a catalytic amount of water directly through at least one ion exchanger to remove the sodium ions, the removal of the sodium ions is carried out in a fully continuous ion exchange unit which comprises: a plurality of ion exchange cells (Z) which are arranged on a rotary platform and are each provided with a distribution element and a collection element and a central valve (V) having a stator disk (S) and a rotor disk (R) via which the introduction and discharge of all liquid streams into or out of the ion exchange unit occurs, and feed and discharge lines from each ion exchange cell (Z) to the central valve (V).

Abstract: Process for the work-up of a mixture comprising ionic liquids and a further substance, wherein the substance present is separated off by means of adsorptive separation processes.

Abstract: The present invention relates to a process for preparing TEDA solutions comprising a solvent selected from the group consisting of polyhydric alcohols and ethers of polyhydric alcohols. The process comprises passing gaseous TEDA into the solvent and subsequently treating the solutions with one or more suitable adsorbents. This gives solutions which have only low color numbers and are color-stable on storage. The solutions can be used as such in preferred applications of TEDA, preferably polyurethane production.

Abstract: The present invention relates to a process for preparing hydroxyl-containing polymers, in particular for preparing polytetrahydrofuran with terminal hydroxyl groups, from the corresponding acyloxy-containing polymers by transesterification with alcohols in the presence of an alkali metal- or alkaline earth metal-containing catalyst, which entails the appropriate acyloxy-containing polymer being introduced together with the alcohol and the catalyst into a first prereactor (I) and converted therein at least partly to the hydroxyl-containing polymer, and the reaction solution being fed into the upper zone (IIa) of a distillation column (II) into whose lower zone (IIb) alcohol in vapor phase is additionally fed. This involves a phase exchange at the coherent and the disperse phase at the transition from the prereactor to the distillation column. Preferably, in addition to the first prereactor, a further 3 prereactors are used which serve as holdup reactors.

Abstract: A process for reducing the amine content of amine-contaminated N-substituted lactams comprises treating the contaminated N-substituted lactams with an acid macroporous cation exchanger.

Abstract: The invention relates to a process for preparing hydroxyl-containing polymers, in particular for preparing polytetrahydrofuran with terminal hydroxyl groups, from the corresponding acyloxy-containing polymers by transesterification with alcohols in the presence of a sodium-containing catalyst. In this process the polytetrahydrofuiran solution is passed in the presence of a catalytic amount of water directly through at least one ion exchanger following the transesterification in order to remove the sodium cations.The novel process makes it possible to remove the sodium cations from the sodium-containing catalyst in an economic manner and with little complexity. The residual sodium content can be reduced to values of less than 0.5 ppm.

Abstract: A process for preparing hydroxyl-containing polymers and, in particular, a process for preparing polytetrahydrofuran with terminal hydroxyl groups from the corresponding acyloxy-containing polymers by transesterification with alcohols is carried out continuously in at least one stirred vessel, with the foam produced in the transesterification being fed tangentially to a cylindrical container, preferably a cyclone separator, at an adequate velocity to destroy the foam. The liquid phase which separates out is recycled through a line to the at least one stirred vessel.This continuous process is preferably carried out in a cascade of stirred vessels, in which each stirred vessel or a subunit of at least two stirred vessels can in each case be coupled to a cylindrical container, preferably in the form of a cyclone separator.