摘要:
Process for preparing polyoxymethylene copolymers (POMs) by a) polymerizing a reaction mixture comprising suitable main monomers and comonomers and also a polymerization initiator and, if appropriate, a regulator, b) adding a deactivator and c) removing the residual monomers, wherein the amount of compounds whose melting point at 1013 hPa is below 60° C. present in the reaction mixture at any point in time during the process is not more than 0.1% by weight, with the POM, the monomers, comonomers, polymerization initiators, deactivators and regulators not being included in the calculation.
摘要:
The invention relates to a method for producing and using a solid sodium diformate having a high formic acid content, to the use thereof in animal foods in the form of an acidifier, preservatives, ensilage auxiliary agents, fertilizers, and a growth and productivity-stimulating agent and the inventive animal food additives containing sodium diformate.
摘要:
A process for preparing butadiene from n-butane, comprising the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively, catalytically dehydrogenating n-butane to obtain a gas stream b comprising n-butane, 1-butene, 2-butene, butadiene and hydrogen, with or without carbon dioxide and with or without steam; C) feeding the gas stream b and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a gas stream c comprising n-butane, butadiene, hydrogen, carbon dioxide and steam, D) compressing in at least one first compression stage and cooling the gas stream c to obtain at least one condensate stream d1 comprising water and a gas stream d2 comprising n-butane, butadiene, hydrogen, carbon dioxide and steam, E) separating the gas stream d2 by extractive distillation into a product stream e1 consisting substantially of butadiene and a stream e2 comprising n-butane, hydrogen, carbon dioxide and steam, F) compressing in at least one further compression stage and cooling the gas stream e2 to obtain at least one condensate stream f1 comprising n-butane and water, and a gas stream f2 comprising n-butane, hydrogen and carbon dioxide, G) cooling the gas stream f2 to obtain a condensate stream g1 comprising n-butane and an offgas stream g2 comprising carbon dioxide and hydrogen, H) removing water from the at least one condensate stream f1 and, if appropriate, from the condensate stream g1 by phase separation to obtain at least one recycle stream hi comprising n-butane and at least one wastewater stream h2, and recycling the at least one recycle stream h1 into the first dehydrogenation zone.
摘要:
Process for producing polymer foams derived from reactive polycondensation resins and having a maximum pore diameter of 1 μm, which comprises: 1) preparing a gelable mixture of the reactive polycondensation resin in a solvent or dispersion medium, 2) preparing an aqueous dispersion comprising polymer particles, 3) mixing the mixture from step 1) with the dispersion from step 2) to give a water-containing gel, and 4) drying the water-containing gel to give the polymer foam, with drying in step 4) being carried out at a pressure and a temperature which are below the critical pressure and below the critical temperature of the liquid phase of the gel and the gel not being brought into contact with an organic liquid to replace the water present in the gel by this liquid after step 3) and before step 4).
摘要:
A process for hydrogenating nitrile functions present in organic compounds over at least one heterogeneous catalyst, in which the hydrogenation is carried out in the presence of an ionic liquid, is described.
摘要:
The invention relates to a method for producing carotenoids or their precursors using genetically modified organisms of the Blakeslea genus. Said method comprises the following steps (i) transformation of at least one of the cells, (ii) optional homokaryotic conversion of the cells obtained in step (i) to produce cells, in which one or more genetic characteristics of the nuclei are all modified in an identical manner and said modification manifests itself in the cells, (iii) selection and reproduction of the genetically modified cell or cells, (iv) cultivation of the genetically modified cells, (v) preparation of the carotenoids produced by the genetically modified cells or the carotenoid precursor produced by said genetically modified cells. The invention also relates to carotenoids or their precursors produced according to said method and to the use thereof.
摘要:
The invention relates to a process for preparing propene from propane, comprising the steps: A) a feed gas stream a comprising propane is provided; B) the feed gas stream a comprising propane and an oxygenous gas stream are fed into a dehydrogenation zone and propane is subjected to a nonoxidative catalytic, autothermal dehydrogenation to propene to obtain a product gas stream b comprising propane, propene, methane, ethane, ethene, C4+ hydrocarbons, carbon monoxide, carbon dioxide, steam and hydrogen, C) the product gas stream b is cooled and steam is removed by condensation to obtain a steam-depleted product gas stream c, D) carbon dioxide is removed by gas scrubbing to obtain a carbon dioxide-depleted product gas stream d, E) the product gas stream d is cooled and a liquid hydrocarbon stream e1 comprising propane, propene, methane, ethane, ethene and C4+ hydrocarbons is removed by condensation to leave a residual gas stream e2 comprising methane, hydrogen and carbon monoxide, F) the liquid hydrocarbon stream e1 is fed into a first distillation zone and separated distillatively into a stream f1 comprising propane, propene and the C4+ hydrocarbons and a stream f2 comprising ethane and ethene, G) the stream f1 is fed into a second distillation zone and separated distillatively into a product stream g1 comprising propene and a stream g2 comprising propane and the C4+ hydrocarbons.
摘要:
A process for preparing cyclododecanone by reacting cyclododecene with dinitrogen monoxide, comprising in particular steps (I) and (II): (I) preparing cyclododecene by partially hydrogenating cyclododecatriene; (II) reacting cyclododecene obtained in (I) with dinitrogen monoxide to obtain cyclododecanone.
摘要:
Process for the production of leather, wherein, after liming, deliming and, if appropriate, pickling, animal hides are pretanned or tanned with a mixture of compounds comprising(a) at least one organic tanning agent and (b) a mixture of (b1) at least one C3-C12-dicarboxylic acid (b2) and at least one further acidic compound selected from C1-C3-mono- or C3-C12-dicarboxylic acids, or salts thereof.
摘要:
Processes comprising: providing a mixture comprising monoethylene glycol and diethylenetriamine; and subjecting the mixture to extractive distillation with a diethylenetriamine-selective solvent comprising triethylene glycol to provide a first stream comprising monoethylene glycol and a second stream comprising diethylenetriamine; wherein the first stream is substantially free of diethylenetriamine, and wherein the second stream is substantially free of monoethylene glycol.