Abstract: Process for preparing chlorine from hydrogen chloride, which comprises the steps: a) feeding of a stream a1 comprising hydrogen chloride and of a stream a2 comprising oxygen into an oxidation zone and catalytic oxidation of hydrogen chloride to chlorine, giving a product gas stream a3 comprising chlorine, water, oxygen, carbon dioxide and inert gases; b) contacting of the product gas stream a3 with aqueous hydrochloric acid I in a phase contact apparatus and partial separation of water and of hydrogen chloride from the stream a3, leaving a gas stream b comprising hydrogen chloride, chlorine, water, oxygen, carbon dioxide and possibly inert gases, with at least 5% of the hydrogen chloride comprised in the stream a3 remaining in the gas stream b; c) drying of the gas stream b) to leave a gas stream c which is substantially free of water and comprises hydrogen chloride, chlorine, oxygen, carbon dioxide and possibly inert gases; d) partial liquefaction of the gas stream c by compression and cooling, giving an at

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: A biodiesel fuel mixture having a cetane number of >40, comprising a) from 1 to 100% by weight of biodiesel, b) from 0 to 98.9% by weight of diesel oil of fossil origin, c) from 0.1 to 20% by weight of polyoxyalkylene dialkyl ether of the formula RO(CH2O)nR ?in which R is an alkyl group having from 1 to 10 carbon atoms and n=from 2 to 10, and d) from 0 to 5% by weight of further additives.

Abstract: A process for preparing polyoxymethylene dialkyl ethers of the formula H2m+1CmO(CH2O)nCmH2m+1 where n=2-10, m, identically or differently,=1 or 2, in which a dialkyl ether selected from dimethyl ether, methyl ethyl ether and diethyl ether, and trioxane are fed into a reactor and reacted in the presence of an acidic catalyst, the amount of water introduced into the reaction mixture by the dialkyl ether, trioxane and/or the catalyst being <1% by weight based on the reaction mixture.

Abstract: A process for preparing polyoxymethylene dimethyl ether of the formula H3CO(CH2O)nCH3 where n=2-10, in which methylal and trioxane are fed into a reactor and reacted in the presence of an acidic catalyst, wherein the amount of water introduced into the reaction mixture by methylal, trioxane and/or the catalyst is <1% by weight based on the reaction mixture. Preferably, a fraction comprising polyoxymethylene dimethyl ether where n=3 and 4 is obtained by distillation from the reaction mixture, and methylal, trioxane and polyoxymethylene dimethyl ether where n<3 and optionally n>4 are recycled into the reaction.

Abstract: A process for working up hydroxylamine-containing solutions as obtained in particular in the electronics industry during the cleaning of electronic components is described. According to the invention, the hydroxylamine is stripped from the wastewater with steam. The products obtained are aqueous hydroxylamine and an aqueous solution of the amines. Both product streams can be purified in further process steps to give a saleable product.

Abstract: In a process for drying microporous, fluid-containing particles, the fluid-containing particles to be dried are fed as a moving bed countercurrently to a drying fluid, the interfacial tension of the fluid being reduced in comparison with the interfacial tension of the fluid at room temperature, at near-critical to supercritical pressure of the fluid, preferably to a value in the range from 0 to {fraction (1/10)}, in particular from 0 to {fraction (1/20)}, of the interfacial tension at room temperature. Furthermore, microporous, three-dimensionally networked particles are prepared by a process comprising preparation of microporous particles containing pore liquid, exchange of the pore liquid in the particles for a fluid and drying of the fluid-containing particles, the exchange and drying being carried out in the moving bed by the countercurrent method.

Abstract: In a process for drying microporous, fluid-containing particles, the heat required for increasing the temperature is supplied by convection by reducing the interfacial tension of the fluid, preferably to 0 to 1/10, in particular to 0 to 1/20, of the interfacial tension of the fluid at room temperature, by appropriately increasing the temperature at from close to the critical pressure to supercritical pressure of the fluid. Furthermore, microporous, three-dimensionally networked particles are prepared by a process in which the drying process is used. In addition, an apparatus is used for carrying out the drying process, the apparatus comprising a pressure container having an inner container and pressure-withstanding outer container and suitable measuring and control apparatuses and pump apparatuses and heat exchangers, the inner container being provided for holding the particles to be dried and a gap being provided between the inner container and the outer container.

Abstract: An aqueous solution of free hydroxylamine is prepared by treating a hydroxylammonium salt with ammonia by the countercurrent method in a stripping column by a process in which hydroxylamine is liberated and at the same time the solution obtained is separated by distillation into an aqueous hydroxylamine solution and a salt fraction. The novel process can be carried out in a simple and gentle manner and on a large scale. The danger of decomposition is minimized owing to the low thermal load, the low concentration of hydroxylamine and the short residence time in the process.

Abstract: A process for working up hydroxylamine-containing solutions as obtained in particular in the electronics industry during the cleaning of electronic components is described. According to the invention, the hydroxylamine is stripped from the wastewater with steam. The products obtained are aqueous hydroxylamine and an aqueous solution of the amines. Both product streams can be purified in further process steps to give a saleable product.

Abstract: A very pure aqueous solution of free hydroxylamine is prepared by a process in which the dilute, aqueous hydroxylamine solution is concentrated in a column by removing hydroxylamine-containing vapors via a side take-off in the bottom of the column, and very pure hydroxylamine is obtained by condensing the vapors. The novel process can be carried out simply, in a gentle manner and on a large scale and gives electronic grade hydroxylamine.