摘要:
In a process for recovering pure methylal from methanol-methylal mixtures, which can optionally contain still further compounds, the separation conducted in a rectification device comprising two rectifying columns. In the first rectifying column, the mixture to be separated is rectified under a pressure lower than that in the second column, into a methylal-rich, methanol-poor distillate, and into a practically methylal-free, methanol-rich sump product. The methylal-rich distillate of the first rectification is then separated in a second rectifying column, operated under a higher pressure than the first rectification column, into a compound stream containing methanol and methylal, which is then recycled to the first rectifying column, and into pure methylal as the sump product. In a specific refinement, the first rectification is preferably operated under a pressure of 1-22 bar absolute and the second rectification preferably under a pressure of 9-30 bar absolute, with the second rectification being operated under a pressure which is at least 8 bar higher than that of the first rectification.
摘要:
A process for preparing fatty acid esters by reacting olefins, alkanols and carbon monoxide in the presence of a compound of cobalt and a promoter consisting of pyridine, non-orthosubstituted alkylpyridines or mixtures thereof. The reaction output is at first treated with a gas containing oxygen in a non-damaging manner and then reprocessed in two distillation stages. The first distillation stage is operated at a higher pressure than the second. In the first distillation stage there is produced a distillate free of cobalt and a sump product containing all of the cobalt used as catalyst. In the second distillation stage the sump product of the first distillation stage is again distilled to produce another distillate free of cobalt and a cobalt concentrate as sump product. This cobalt concentrate is incorporated into pyridine, a non-orthosubstituted alkylpyridine or a mixture thereof to form a suspension. The suspension is then treated by a mixture of carbon monoxide and hydrogen at a temperature of 100.degree. to 250.degree. C. and a pressure at least 50 bars, and this treatment product is fed back into the fatty acid ester synthesis.
摘要:
For producing 2,6-di-tert-butylphenol and products therefrom, utilizing small quantities of aluminum tris-(2-tert-butylphenolate as a catalyst by reaction of 2-tert-butylphenol with isobutene in the liquid phase, the reaction is performed in the presence of diluents such as liquid saturated aliphatic or cycloaliphatic hydrocarbons, C.sub.5 -C.sub.16 alkenes of formula R.sub.1 --CH.dbd.CH.sub.2 or R.sub.2 --CH.dbd.CH--R.sub.3, C.sub.5 to C.sub.12 cycloalkenes, which contain no branching on the C.dbd.C-bond, excess isobutene or mixtures thereof, at temperatures of 0.degree. C. to 80.degree. C., pressures of 0.1 to 11 bars and catalyst amounts of 0.005 to 5 mol %, based on 2-tert-butylphenol. High conversions are obtained with few undesirable trialkylated products.
摘要:
A process for the continuous separation of methanol and water from a feed mixture containing predominantly tetrahydrofuran admixed with water, methanol and small amounts of additional compounds, in a rectifying apparatus having at last two rectifying columns, of which two are operated at different pressures which involves feeding the raw material into a first column operated under lower pressure, and introducing the distillate from the column operated under a lower pressure to a second column operated under a higher pressure, while a product stream from the second column operated under a higher pressure is reintroduced into the first column operated under a lower pressure. In this process the product stream withdrawn from the second column operated under a higher pressure is withdrawn as a side stream from the stripping or enrichment section of the second column and is returned into the first column operated under a lower pressure, while a methanol-enriched product stream containing practically all of the methanol introduced with the raw material into the rectifying apparatus is withdrawn from the head of the second column operated under a higher pressure. The first column is operated for example at atmospheric pressure and the second column is operated at a pressure of from 1 to 25 bar.
摘要:
A method for preparing carboxylic acid alkylester after products free of nitrogen containing compounds. These after products, free of nitrogen containing compounds, are prepared by:(1) reacting olefins with carbon monoxide and alkanols in the presence of a catalyst system consisting of a cobalt compound and pyridine, non-orthosubstituted alkylpyridines or a mixture of these pyridines at elevated pressures and elevated temperatures to produce carboxylic acid alkylesters containing nitrogenated compounds resulting from the pyridines;(2) hydrogenating the carboxylic acid alkylesters to produce after products which include alcohols; and(3) treating the after products with acid ion exchangers to remove the nitrogenated compounds.
摘要:
The processing of liquid chlorinated hydrocarbon residues, which may contain solids and which form viscous to solid deposits during the separation of readily boiling components, into(1) distillable organic components,(2) hydrogen chloride, and(3) solid matter with a low chlorine content,is improved by gently concentrating the residues in a first step and, in a second step, decomposing the residues at temperatures of about 200.degree.-400.degree. C., preferably 270.degree.-330.degree. C., with a continuous separation of the vapor phase components from the solid components.
摘要:
A separation of mixtures of water and 2,6-dimethylmorpholine is carried out by rectifying the mixtures at a pressure at the head of the column between 6 and 150 mbars. The separated 2,6-dimethylmorpholine has a maximum water content of 500 ppm by weight and it is possible to achieve for a corresponding design of the rectification water contents of less than 1 ppm by weight of dimethylmorpholine.
摘要:
A process for producing predominantly linear aliphatic carboxylic acid esters by reacting olefins, carbon monoxide and alkanols at elevated pressures and elevated temperatures in the presence of a catalyst consisting of a cobalt compound and a promoter. The promoter is the possibly cobalt-free mixture of substances obtained when a reaction mixture that was prepared by reacting olefins, carbon monoxide and alkanol in the presence of a catalyst consisting of a cobalt compound and pyridine, a non-ortho-substituted alkylpyridine or mixtures at elevated pressure and elevated temperature is reprocessed. This mixture of substances has a higher boiling point than the esters formed as the reaction product and higher than the pyridine, non-ortho-substituted alkylpyridine or mixtures thereof used as the catalytic component.
摘要:
A process for the production of alkyl esters of saturated aliphatic carboxylic acids made by reacting olefins with carbon monoxide and alkanol in the presence of a catalyst consisting of a cobalt compound and a promoter selected from pyridine, a non-ortho-substituted alkylpyridine or mixtures thereof at elevated pressure and temperature and with feedback of unconverted input materials, the water contained in the reaction mixture being separated as much as possible during the reprocessing from the flows of substances slated for feedback.
摘要:
A process for recovering and reactivating catalysts used in the reaction of olefins with carbon monoxide and alkanols. The catalysts consist of a cobalt compound and pyridine, a non-ortho-substituted alkylpyridine or a mixture thereof as the promoter. The reacted mixture contains fatty acid ester, unconverted alkanol, uncoverted olefin, catalyst and promoter and this reacted mixture is treated with oxygen or an oxygenated gas at a temperature of about 20.degree.-150.degree. C. to oxidize the cobalt compound. The oxidized mixture is then separated by distillation to remove unconverted alkanol and olefin, the promoter, the reaction products and the distillation residue obtained thereby is mixed with pyridine, a non-ortho-substituted alkylpyridine or a mixture thereof. The suspension so obtained is treated with a mixture of carbon monoxide and hydrogen at a temperature of 100.degree. to 250.degree. C. and at a pressure of at least 50 bars.