Abstract:
Fuel mixture comprising (i) diesel oil and (ii) polyoxymethylene dialkyl ether of the general formula 1: R-O-(CH2O)n-R', where R and R' are defined as follows: R: methyl, ethyl, propyl, butyl, R': methyl, ethyl, propyl, butyl, n: 2, 3, 4, 5, 6, 7, 8, where the fuel mixture has sulfur content of
Abstract:
The invention relates to a method for producing isocyanates from the corresponding amines and phosgene by carrying out the reaction in the gas phase in at least one reaction zone and guiding the reaction mixture to at least one zone in which at least one liquid is injected to terminate the reaction, a zone with an expanded or constant cross-section being present between the reaction zone and the zone in which the reaction termination is brought about.
Abstract:
The invention relates to a multi-stage method for continuously producing organic, distillable polyisocyanates, preferably diisocyanates, especially preferred aliphatic or cycloaliphatic diisocyanates, by reacting the corresponding organic polyamines with urea to give low-molecular monomeric polyureas. The invention also relates to the thermal decomposition of said substances.
Abstract:
A process for preparing tri- and tetraoxymethylene glycol dimethyl ether (POMDMEn=3,4) by reacting formaldehyde with methanol and subsequently working up the reaction mixture by distillation, comprising the steps of: a) feeding aqueous formaldehyde solution and methanol into a reactor and reacting to give a mixture a comprising formaldehyde, water, methylene glycol (MG), polyoxymethylene glycols (MGn>1), methanol, hemiformals (HF), methylal (POMDMEn=1) and polyoxymethylene glycol dimethyl ethers (POMDMEn>1); b) feeding the reaction mixture a into a first distillation column and separating into a low boiler fraction b1 and a high boiler fraction b2 comprising formaldehyde, water, methanol, polyoxymethylene glycols, hemiformals and polyoxymethylene glycol dimethyl ethers (POMDMEn>1); c) feeding the high boiler fraction b2 into a second distillation column and separating into a low boiler fraction c1 comprising formaldehyde, water, methylene glycol, polyoxymethylene glycols, methanol, hemiformals, di-, tri- and tetraoxymethylene glycol dimethyl ether (POMDMEn=2,3,4) and a high boiler fraction c2; d) feeding the low boiler fraction c1 into a third distillation column and separating into a low boiler fraction d1 and a high boiler fraction d2 substantially consisting of formaldehyde, water, methylene glycol, polyoxymethylene glycols, tri- and tetraoxymethylene glycol dimethyl ether (POMDMEn=3,4); e) feeding the high boiler fraction d2 into a phase separation apparatus and separating into an aqueous phase e1 substantially consisting of formaldehyde, water, methylene glycol and polyoxymethylene glycols, and an organic phase e2 comprising tri- and tetraoxymethylene glycol dimethyl ether (POMDMEn=3,4); f) feeding the organic phase e2 into a fourth distillation column and separating into a low boiler fraction f1 substantially consisting of formaldehyde, water, methylene glycol and polyoxymethylene glycols, and a high boiler fraction f2 substantially consisting of tri- and tetraoxymethylene glycol dimethyl ether (POMDMEn=3,4).
Abstract:
The invention relates to a method for preparing isocyanate adducts, comprising the following steps a) the isocyanate adduct is reacted with pure ammonia, b) the reaction product arising in step a) is then prepared and, c) the formed amines are guided back into the isocyanate production.