摘要:
A process is described for the production of butane-1,4-diol, η-butyrolactone and/or tetrahydrofuran. A vaporous stream containing maleic anhydride, water, and carbon oxides is contacted in an absorption zone with a high boiling ester as solvent to form a solution of maleic anhydride in the high boiling ester which has a boiling point at the atmospheric pressure at least about 30 °C higher than that of maleic anhydride and is selected from di-(C1 to C4 alkyl) esters of alkyl dicarboxylic acids containing up to 13 carbon atoms, mono- and di-(C10 to C18 alkyl) esters of maleic acid, fumaric acid, succinic acid, and mixtures thereof, (C1 to C4 alkyl) esters of naphthalene-monocarboxylic acids, tri-(C1 to C4 alkyl) esters of aromatic tricarboxylic acids, and di-(C1 to C4 alkyl) esters of isophthalic acid. The maleic anhydride in the solution is stripped with a gaseous stream containing hydrogen thereby forming a vaporous stream comprising hydrogen and maleic anhydride, which is contacted in a hydrogenation zone with a heterogeneous hydrogenation catalyst to convert maleic anhydride to at least one C4 compound selected from butane-1,4-diol, η-butyrolactone and tetrahydrofuran.
摘要:
The invention relates to a method for the production of alcohols, by catalytic hydrogenation of carbonyl compounds, using a catalyst with 0,01 to 50 wt. % rhenium and 0 to 20 wt. % of a further metal, chosen from Zn, Cu, Ag, Au, Ni, Fe, Cr or V, based upon total catalyst weight, supported on oxidatively pre-treated activated charcoal.
摘要:
A method for continuously producing a dialkyl carbonate and a diol, comprising: (1) continuously feeding a cyclic carbonate and an aliphatic monohydric alcohol to a continuous multi-stage distillation column, and continuously effecting a transesterification between the cyclic carbonate and the aliphatic monohydric alcohol in the presence of a transesterification catalyst in the distillation column, while continuously withdrawing a low boiling point mixture in a gaseous form containing the produced dialkyl carbonate and the unreacted aliphatic monohydric alcohol from an upper portion of the distillation column and continuously withdrawing a high boiling point mixture in a liquid form containing the produced diol and the unreacted cyclic carbonate from a lower portion of the distillation column, and (2) continuously feeding the high boiling point mixture withdrawn from the lower portion of the distillation column to a continuous etherification reactor, to thereby effect a continuous etherification reaction between the unreacted cyclic carbonate and a part of the produced diol and produce a chain ether and carbon dioxide, while continuously withdrawing the resultant etherification reaction mixture containing the remainder of the diol produced in step (1) and the produced chain ether from the continuous etherification reactor, wherein the etherification reaction mixture has a cyclic carbonate content of from 0 to 10 -2 in terms of the weight ratio of the cyclic carbonate to the diol.
摘要:
Geformte Raney-Metallfestbettkatalysatoren werden mit Rhenium dotiert. Sie können für die Hydrierung gesättigter oder ungesättigter Ester in ihre entsprechenden Mono- oder Mehrfachhydroxyalkohole verwendet werden.
摘要:
A process for removing precursors, such as low boiling alkyl glycols (e.g., ethylene glycol and/or 1,2-propylene glycol), to undesirable color forming acetal impurities (e.g., 1,3-dioxolane and 4-methyl-1,3-dioxolane) from technical grade 1,4-butanedio1/2-methyl-1,4-butanediol mixtures and the like by distillative topping of the diol mixture prior to ring closing cyclization to corresponding tetrahydrofuran/3-methyl tetrahydrofuran mixture and subsequent polymerization to polytetramethylene glycol ether polymers. Such a process is useful to produce THF and PTMEG having an APHA color index of nearly zero.
摘要:
The invention relates to a method for producing alkylene glycol or a mixture of two different alkylene glycols, wherein a reaction mixture containing at least one alkylene oxide or a mixture of two or more different alkylene oxides, a catalyst and water are made to react. The catalyst can not be dissolved in the reaction mixture and has at least one covalently linked acid functional group and at least one covalently linked basic functional group. The invention also relates to a moulded body with at least one acid group and at least one basic functional group, whereby the functional groups are covalently linked to the support.
摘要:
The invention relates to a method for producing aliphatic alcohols by hydrogenating aliphatic carboxylic acids, anhydrides or esters thereof or lactones in the presence of a catalyst containing Pt and Re in metallic or oxidic form. Said catalyst also contains at least one other element from groups 5 to 12 and 14 and from the group of lanthanides of the periodic table of elements in metallic or oxidic form.