摘要:
A method of producing acetaldehyde hydrogenates acetic acid in the presence of an iron oxide catalyst containing between 2.5 and 90 wt % Pd, more preferably 10 and 80 wt % Pd and most preferably 20 and 60 wt % Pd. The catalyst has a specific surface area of less than 150 m.sup.2 /g. Hydrogen and acetic acid are fed to a reactor in a hydrogen to acetic acid ratio of 2:1 to 25:1, more preferably in a hydrogen to acetic acid ratio of 3:1 to 15:1 and most preferably in a hydrogen to acetic acid ratio of 4:1 to 12:1. The hydrogenation is performed at a temperature of about 250.degree. C. to 400.degree. C., more preferably about 270.degree. C. to 350.degree. C. and most preferably about 280.degree. C. to 325.degree. C. The hydrogenation of acetic acid produces a partially gaseous product, and acetaldehyde is absorbed from the partially gaseous product with a solvent containing acetic acid. The gas remaining after the absorption step contains hydrogen, and this gas is recycled for the hydrogenation of acetic acid. The absorbed acetaldehyde is distilled to isolate same. After acetaldehyde is isolated from unreacted acetic acid and the other products via distillation, the unreacted acetic acid is separated from the other products using azeotropic distillation. Water is contained in the other products, and the azeotrope is an azeotrope of ethyl acetate and water. The unreacted acetic acid is separated in a column, and the column is controlled to contain an ethyl acetate rich azeotrope of ethyl acetate and water.
摘要:
A process for iodinating aromatic compounds, comprising the steps of iodinating an aromatic compound, separating a desired iodoaromatic product from the product mixture, purifying said desired iodoaromatic product, and isolating said desired product.
摘要:
Disclosed is an improved process for the preparation of 1,4-butenediol by the hydrolysis of 3,4-epoxy-1-butene (EpB) wherein a mixture of EpB and water is contacted with a catalyst comprising a catalyst support material an copper in a positive valence state.
摘要:
A process for the vapor phase iodination of an aromatic compound which involves combusting an alkyl aromatic iodide in the presence of oxygen to produce molecular iodine and feeding the molecular iodine and an aromatic compound to an oxyiodination reaction to iodinate aromatic compounds.
摘要:
A process for iodinating an aromatic compound in which a source of iodine is reacted with the aromatic compound in the presence of oxygen over a non-acid catalyst wherein the aromatic compound has a fluoro, chloro, bromo, iodo, hydroxy or cyano group.
摘要:
The preparation of acetic anhydride by the carbonylation of methyl acetate in the presence of rhodium, an iodine compound and lithium at elevated temperatures and pressures is improved by the inclusion of about 2 to 7 volume percent hydrogen in the gas fed to the carbonylation reactor. The presence of hydrogen suppresses tar formation and increases reaction rate.
摘要:
A process useful for the recovery of terephthalic acid and ethylene glycol from poly(ethylene terephthalate) or its copolymers. The process is economical, beneficial to the environment and provides polymer grade terephthalic acid and ethylene glycol from post-consumer resin. The process is a six-step process including: (1) contacting a resin containing poly(ethylene terephthalate) with water at elevated temperature and pressure, (2) cooling the resulting mixture to provide a solid portion containing terephthalic acid and a liquid portion containing ethylene glycol, (3) recovery of the ethylene glycol from the liquid portion by distillation, (4) recovery of the terephthalic acid by heating the solid portion in the presence of water vapor at elevated temperature to produce a vapor containing terephthalic acid and water, (5) cooling terephthalic acid water vapor mixture to a temperature below the dew point of terephthalic acid and (6) collecting the polymer grade terephthalic acid. The polymer grade terephthalic acid and ethylene glycol provided by this process can be used to make high quality terephthalate homopolymers or copolymers for applications including clear bottles and fibers.
摘要:
The process relates to a process for the vapor phase bromination of aromatic compounds in the presence of oxygen and a catalyst comprising an oxidizing metal and an inert support.
摘要:
The invention relates to a process for isomerizing iodoaromatic compounds over a non-acidic zeolite catalyst in the liquid or gas phase in the presence of a source of iodine.