摘要:
An process for preparing 3-pentenenitrile by hydrocyanating 1,3-butadiene, in which the process yield with regard to recycled 1,3-butadiene is maximized.
摘要:
A method for producing 3-pentenenitrile by means of the hydrocyanation of 1,3-butadiene, which comprises the following process steps: (b′) distillation of 1,3-butadiene comprising water, 1- and 2-butenes and a stabilizer in a distillation apparatus K4 to obtain a stream 15 as the bottom product, which comprises dried 1,3-butadiene, 1- and 2-butenes and the stabilizer, and a stream 16 as the top product, which comprises an azeotropic 1,3-butadiene/water mixture, condensation of the stream 16 in a condenser W, transfer of the resulting condensate (stream 17) into a phase separation apparatus, recycling of the upper liquid phase (stream 18) consisting of 1,3-butadiene as reflux to the column K4, and discharge of the lower liquid aqueous phase (stream 19), (a) reaction of stream 15 in a reactor R1 with hydrogen cyanide over at least one catalyst (stream 6d) to obtain a stream 1 which comprises 3-pentenenitrile, 2-methyl-3-butenenitrile, the at least one catalyst, unconverted 1,3-butadiene, and 1- and 2-butenes, with or without residues of unconverted hydrogen cyanide, (b) distillation of stream 1 in a distillation apparatus K1 to obtain a stream 2 as the top product, which comprises the predominant portion of the 1,3-butadiene from stream 1, and to obtain a stream 3 as the bottom product, which comprises 3-pentenenitrile, the at least one catalyst, 2-methyl-3-butenenitrile, 1- and 2-butenes and the remaining proportion of the 1,3-butadiene from stream 1 which has not been removed in stream 2, (c) distillation of stream 3 in a distillation apparatus K2 to obtain a stream 5 at a side draw of the column, which 3-pentenenitrile and 2-methyl-3-butenenitrile, a stream 6 as the bottom product, which comprises the at least one catalyst, and a stream 4 as the top product, (d) compression of stream 4 in the compressor V1, discharge of a gaseous substream 4b which comprises 1- and 2-butenes, transfer of the compressed stream 4a into the condenser W1, combined cond. With stream 2 from b) in combined condensation of this stream 2 from b) and transfer of the condensate as stream 9, partly as reflux to the column K1 (stream 9b), partly as return stream into the reactor R1 (stream 9a), and (e) distillative separation of stream 5 to obtain 3-pentenenitrile and 2-methyl-3-butenenitrile.
摘要:
Process for recovering cyclododecatriene (CDT) from a solution comprising CDT and high boilers such as deactivated catalyst and polymers, which comprises feeding the solution into a preheater and heating it, subsequently depressurizing it through a downstream pressure maintenance device and feeding the resulting two-phase mixture into a helical tube evaporator and there reducing the CDT content of the liquid phase by partial evaporation and discharging a gaseous product stream having an increased concentration of CDT.
摘要:
Process for recovering cyclododecatriene (CDT) from a solution containing CDT and high boilers such as deactivated catalyst and polymers, which includes feeding the solution into a preheater and heating it, subsequently depressurizing it through a downstream pressure maintenance device and feeding the resulting two-phase mixture into a helical tube evaporator and there reducing the CDT content of the liquid phase by partial evaporation and discharging a gaseous product stream having an increased concentration of CDT.
摘要:
A process for separating water from pyrolysis gasoline obtained from a steam cracking step uses a coalescer for the water separation. And a device comprises a coalescer for water separation from pyrolysis gasoline.
摘要:
A process for hydrogenating an organic compound which has at least one carbonyl group, in which the organic compound is hydrogenated in the presence of a shaped article which contains (i) an oxidic material comprising copper oxide, aluminum oxide and lanthanum oxide, and (ii) powdered metallic copper, copper flakes, powdered cement, graphite or a mixture thereof, is provided.
摘要:
A process for preparing heteroaromatic alcohols by catalytically hydrogenating heteroaromatic carboxylic acids or esters thereof by hydrogenating with hydrogen in the presence of a ruthenium-phosphine complex in an organic solvent.
摘要:
The invention relates to a method for hydrogenation of an organic compound comprising at least one carbonyl group, whereby the organic compound is brought into contact with a moulded body in the presence of hydrogen. Said body may be produced by a method in which (i) an oxidic material is prepared, comprising copper oxide, aluminium oxide, and at least one oxide of lanthanum, tungsten, molybdenum, titanium, or zirconium, followed by (ii) addition of powdered metallic copper, copper platelets, powdered cement, graphite, mixtures or a mixture thereof with graphite to the oxidic material and (iii) moulding the mixture from (ii) to give a moulded body, characterised in that the moulded body is in the form of catalyst tablets or catalyst extrudates with a diameter d and/or height h
摘要:
Surfactants of the general formula R1—X where R1 is an aliphatic C17H35-alkyl radical and X is a hydrophilic group, and the mean degree of branching of the R1 radical is from 2.8 to 3.7. Mixtures which comprise such surfactants and the use of such surfactants and of mixtures thereof for tertiary mineral oil extraction.
摘要:
The invention relates to a process for preparing polyether alcohols, which comprises the steps a) reaction of an unsaturated natural oil or fat with a mixture of carbon monoxide and hydrogen, b) reaction of the mixture from step a) with hydrogen, c) reaction of the product from step b) with an alkylene oxide in the presence of a catalyst.