Abstract:
The present invention relates to a continuous process for producing an alkylene oxide by direct oxidation of an alkene with oxygen by reacting a mixture comprising alkene and oxygen in the presence of a silver-comprising catalyst for a run time Δt(i), wherein during the oxidation, the catalyst is additionally contacted at least once with a further mixture comprising ethanol for a run time Δt(ii), wherein the run time Δt(i)>Δt(ii).
Abstract:
Apparatus and processes are provided for forming epoxide compounds. In one embodiment, a process for the manufacture of an epoxide is provided including adding an oxidant, a water-soluble manganese complex and a terminal olefin to form a multiphasic reaction mixture, reacting the terminal olefin with the oxidant in the multiphasic reaction mixture having at least one organic phase in the presence of the water-soluble manganese complex, separating the reaction mixture into the at least one organic phase and an aqueous phase, and reusing at least part of the aqueous phase. The invention is also related to a device for performing the above process.
Abstract:
A catalyst for the production of ethylene oxide in high efficiency and high selectivity, as well as stably for a long period of time is provided.A catalyst for the production of ethylene oxide comprising silver and a reaction promoter supported on a porous carrier comprising α-alumina as a main component, characterized in that a relative standard deviation of silver supporting rate of each particle of the catalyst is 0.001 or more and 0.1 or less.
Abstract:
The present invention provides a process for removing oxygenate from an olefin stream comprising oxygenate, comprising providing to an oxygenate recovery zone the olefin stream comprising oxygenate and a solvent comprising ethanol, treating the olefin stream comprising oxygenate with the solvent, and retrieving from the oxygenate recovery zone at least one oxygenate-depleted olefinic product stream comprising olefin and a spent solvent comprising at least part of the oxygenate.
Abstract:
The present invention provides an efficient method of synthesizing and purifying dianhydrohexitols such as dianhydrogalactitol. In general, as applied to dianhydrogalactitol, the method comprises: (1) reacting dulcitol with a concentrated solution of hydrobromic acid at a temperature of about 80° C. to produce dibromogalactitol; (2) reacting the dibromogalactitol with potassium carbonate in t-butanol to produce dianhydrogalactitol; and (3) purifying the dianhydrogalactitol using a slurry of ethyl ether to produce purified dianhydrogalactitol. Another method produces dianhydrogalactitol from dulcitol; this method comprises: (1) reacting dulcitol with a reactant to convert the 1,6-hydroxy groups of dulcitol to an effective leaving group to generate an intermediate; and (2) reacting the intermediate with an inorganic weak base to produce dianhydrogalactitol through an intramolecular SN2 reaction. Other methods for the synthesis of dianhydrogalactitol from dulcitol are described.
Abstract:
A method for preparing an epoxide is disclosed. The method for preparing an epoxide includes the step of performing a reaction of an alkene and oxidant in the presence of a Ti—Si molecular sieve as a catalyst, and increases the conversion rate of hydrogen peroxide and the yield of the epoxide.
Abstract:
The present invention relates to a process for preparing ethylene oxide by reaction of ethylene with oxygen in the presence of at least one silver-comprising catalyst, wherein the reaction takes place in a reactor which has a catalyst packed bed having at least two zones (i) and (ii) and the silver content of the catalyst in zone (i) is lower than the silver content of the catalyst in zone (ii). The catalyst packed bed preferably has a further zone (a) with which the reaction mixture comes into contact before the zones (i) and (ii). According to the invention, the silver content of the catalyst in the zone (a) is higher than the silver content of the catalyst in zone (i).
Abstract:
The present invention provides a reactor system comprising: —one or more purification zones comprising an absorbent which comprises silver, an alkali or alkaline earth metal, and a support material having a surface area of more than 20 m2/g, and —a reaction zone comprising a catalyst, which reaction zone is positioned downstream from the one or more purification zones; an absorbent; a process for reacting a feed comprising one or more feed components; and a process for preparing a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine.
Abstract:
A process for the production of an olefin oxide, which process comprises reacting a feed comprising an olefin and oxygen in a reactor tube in the presence of a silver-containing catalyst, wherein the presence of water in the catalyst bed is controlled such that the ratio of the partial pressure of water (PPH2O) divided by the vapor pressure of water (VPH2O) is less than 0.006, preferably less than 0.004.
Abstract:
The present invention provides a method for start-up of an Oxygenate-to-Olefins process, which process comprises the steps: a) providing an oxygenate-comprising feedstock to an Oxygenate-to-Olefins reaction zone and contacting the feedstock with a zeolite-comprising catalyst at a temperature in the range of from 450 to 700° C. ° C., to obtain an reaction product containing olefins; b) separating the reaction product obtained in step a) in at least a product fraction containing ethylene and/or propylene and a product fraction containing C4+ olefins; c) recycling at least part of the C4+ olefins in the product fraction containing C4+ olefins to the Oxygenate-to-Olefins reaction zone in step (a), characterised in that upon start-up the oxygenate-comprising feedstock initially comprises a first amount of externally supplied tert-alkyl ether and subsequently the amount of externally supplied tert-alkyl ether in the oxygenate-comprising feedstock is reduced.