摘要:
The present invention relates to a process for preparing low molecular weight aromatic materials of value from a lignin-comprising starting material produced from biomass.
摘要:
The present invention relates to a process for preparing polyisocyanates from natural raw material sources, in which a composition comprising low molecular weight aromatics which comprise at least one hydroxy group or at least one alkoxy group per molecule (oxyaromatics) is produced from a biomass material, these oxyaromatics are converted into the corresponding aromatic amines and, optionally after condensation with formaldehyde, reacted further with phosgene to give compounds comprising isocyanate groups.
摘要:
The present invention relates to a process for preparing polyisocyanates from natural raw material sources, in which a composition comprising low molecular weight aromatics which comprise at least one hydroxy group or at least one alkoxy group per molecule (oxyaromatics) is produced from a biomass material, these oxyaromatics are converted into the corresponding aromatic amines and, optionally after condensation with formaldehyde, reacted further with phosgene to give compounds comprising isocyanate groups.
摘要:
Composite membranes comprising at least one porous substrate layer and at least one microporous separation layer, comprising at least one zeolite of the MFI type, are described, the separation layer being produced by a hydrothermal synthesis in which the molar ratio of silicon to aluminum is greater than 120 and the separation layer contains less than 10% by weight of aluminum in elemental or chemically bound form in a zone of at least 100 nm adjacent to the separation layer.
摘要:
The present invention relates to a method for the isolation of olefins from a gas mixture comprising one or more olefins, inert gas and catalyst poison, where the gas mixture is fed to a separation unit (18) and separated into olefin and inert gas. The method according to the invention has the special feature that an apparatus (17) is installed upstream or downstream of the separation unit (18) and that i) in the case of an upstream apparatus (17), the catalyst poison is at least partially removed from the gas mixture, and ii) in the case of a downstream apparatus (17), the catalyst poison is at least partially removed from the separated-off olefin. The olefins here are preferably isolated from a gas mixture formed as offgas in catalytic gas-phase polymerization for the preparation of polyolefins. The recovery of the olefins from the offgas is of economic importance.
摘要:
Process for the work-up of naphtha, wherein a) naphtha or a stream produced from naphtha in a pretreatment step is separated in a membrane unit into a stream A which is depleted in aromatics and a stream B which is enriched in aromatics, with the aromatics concentration in stream A being from 2 to 12% by weight (step a), b) at least part of the substream A is fed to a steam cracker (step b), c) at least part of the substream B is fed to a unit in which it is separated by means of a thermal process into a stream C which has a lower aromatics content than stream B or a plurality of streams C′, C″, C′″ . . . which each have lower aromatics contents than stream B and a stream D which has a higher aromatics content than stream B or a plurality of streams D′, D″, D′″ . . . which each have higher aromatics contents than stream B (step c), and d) the stream C or at least one of the streams C′, C″, C′″, in each case in part or in its entirety, is added to the feed to the steam cracker or fed into the steam cracker itself (step d).
摘要:
The present invention relates to a process for separating at least one propylene glycol from a mixture (M) comprising water and said propylene glycol, said process comprising (I) evaporating the mixture in at least two evaporation and/or distillation stages at decreasing operating pressures of the evaporators and/or distillation columns obtaining mixture (M′) and mixture (M″); (II) separating the mixture (M′) obtained in (I) in at least one further distillation step, obtaining a mixture (M-I) comprising at least 70 wt.-% of water and a mixture (M-II) comprising less than 30 wt.-% of water.
摘要:
Process for the work-up of naphtha, wherein a) naphtha or a stream produced from naphtha in a pretreatment step is separated in a membrane unit into a stream A which is depleted in aromatics and a stream B which is enriched in aromatics, with the aromatics concentration in stream A being from 2 to 12% by weight (step a), b) at least part of the substream A is fed to a steam cracker (step b), c) at least part of the substream B is fed to a unit in which it is separated by means of a thermal process into a stream C which has a lower aromatics content than stream B or a plurality of streams C′, C″, C′″ . . . which each have lower aromatics contents than stream B and a stream D which has a higher aromatics content than stream B or a plurality of streams D′, D″, D′″ . . . which each have higher aromatics contents than stream B (step c), and d) the stream C or at least one of the streams C′, C″, C′″, in each case in part or in its entirety, is added to the feed to the steam cracker or fed into the steam cracker itself (step d).
摘要:
The present invention relates to a process for preparing hydroformylation products of olefins having at least four carbon atoms, in which a high proportion of both the linear Ci-olefins having a terminal double bond comprised in the olefin-comprising feed used and of the linear Ci-olefins having an internal double bond is converted into hydroformylation products. Furthermore, the invention relates to a process for preparing 2-propylheptanol which comprises such a hydroformylation process.
摘要:
The invention relates to an improved method for the production of D-pantothenic acid and/or salts thereof and use thereof as adjunct for animal feedstuffs.