Abstract:
The object of the present invention is an integrated method for the continuous production of 1,4-butanediol, comprising the following steps: (I) reacting formaldehyde with acetylene in the presence of a catalyst comprising copper at a pH value between 5 and 8, and at a molar ratio of formaldehyde to acetylene of a maximum of 2:1, (II) intermediate buffering of the resulting aqueous mixture comprising butanediol for 0.1 to 100 h, (III) hydrating the mixture obtained after intermediate buffering, and (IV) distilling the hydrogenation product obtained in step II for yielding 1,4-butanediol.
Abstract:
The invention relates to a method for purifying 1,4-butynediol, in which 1,4-butynediol is processed in a dynamic mixing device in an inert gas atmosphere at 25 to 150 °C at a velocity gradient exceeding 100,000 sec-1 in the radial play between the rotor and the stator, one waits for the phases to separate at temperatures ranging from 25 to 150 °C, and the bottom phase is eliminated. Also disclosed is a method for hydrogenating 1,4-butynediol into 1,4-butenediol and 1,4-butanediol with the aid of the purified 1,4-butynediol.
Abstract:
The invention relates to a method for producing monoethylene glycol (MEG) via the metal-catalysed reaction of an oxalic acid dialkyl ester of formula (I), in which R 1 and R 2 each independently of one another represent methyl, ethyl, n-propyl or iso-propyl groups, with hydrogen (H 2 ), wherein the oxalic acid dialkyl ester (I) is used in the form of a melt or dissolved in a solvent, oxalic acid dialkyl ester (I) and H 2 are used in a molar ratio of H 2 :oxalic acid dialkyl ester (I) in the region of 4.0 to 30, and the reaction is carried out continuously in a reactor at a sectional density of ≥ 10 m/s, a temperature in the region of 150 to 270°C, a pressure in the region of 150 to 390 bar and in the presence of a chrome-free, heterogeneous, copper-containing catalyst.