摘要:
A process for the separation of propylene glycol from a mixture of low-boiling fatty alcohols and propylene glycol which comprises extracting the mixture with water to produce a water-propylene glycol mixture and fractionating the water-propylene glycol mixture to produce propylene glycol that is substantially anhydrous and an apparatus for carrying out the process.
摘要:
The glycerol water (sweet water) accumulating in the high-pressure hydrolysis of natural fats and oils with steam into fatty acid and glycerol is continuously purified. Fats larger than 100 .mu.m in diameter are separated from the aqueous phase in a plate-type phase separator and are returned to the high-pressure hydrolysis process. The aqueous phase thus prepurified is passed through a cross-flow filtration membrane, more particularly a microfiltration membrane, and the concentrate is returned to the entrance of the plate-phase separator. Large product streams of glycerol water can be purified continuously, effectively and particularly economically despite frequent changes of provenance.
摘要:
Aliphatic alcohols with up to 30 and especially with 6 to 18 carbon atoms are separated from a mixture of alkyl glycosides and alcohols which are unreacted during the production of these glycosides, by single or multi-stage distillation. The alcohols are distilled off by a drop film evaporator to impoverish the reaction mixture to residual alcohol contents of 5 wt % and under. The strip load of the drop film evaporator is set to at least 1.0 m.sup.3 /h m, especially at least 1.8 m.sup.3 /h m and preferably at least 3.0 m.sup.3 /h m. It is possible to reduce the alcohol content of the product to any value between 0.1 and 5 wt % at acceptable overall cost.
摘要翻译:通过单阶段或多阶段蒸馏,在生产这些糖苷期间将具有多达30个,特别是6至18个碳原子的脂族醇从烷基糖苷和醇的混合物中分离出来,所述烷基糖苷和醇是未反应的。 通过滴膜蒸发器蒸馏掉醇,将反应混合物贫化至5重量%以下的残留醇含量。 降膜蒸发器的带材负载设定为至少1.0m 3 / h m,特别是至少1.8m 3 / h m,优选至少3.0m 3 / h m。 可以以可接受的总成本将产品的醇含量降低至0.1至5重量%之间的任何值。
摘要:
Starting from a mixture containing tocopherol, fats and/or fat derivatives, more particularly fatty acids, and optionally sterol and/or sterol derivatives, the free fatty acids present in the mixture are esterified with an alcohol. The mixture is then transesterified with an alcohol in the presence of a basic catalyst. After the transesterification, the excess lower alcohol is distilled off from the reaction mixture. The transesterification catalyst and the glycerol present, if any, are removed and the fatty acid alkyl ester is distilled off from the mixture. Distillation of fatty acid alkyl esters can be accomplished with a packed column in sequence with a wiped film evaporator. The simultaneous recovery of tocopherol and sterol is possible. Tocopherols and sterols can be separated by the crystallization of sterols from a blend of organic solvents.
摘要:
A process for the nondegenerative distillation of C.sub.6 -C.sub.24 -fatty acids, of the type obtained by splitting natural fats and oils or by synthetic processes, such as for example the oxidation of paraffins, the crude product is thermally dried under reduced pressure, the dried and heated crude product is subjected to fractional evaporation in falling-film evaporators, optionally in the presence of superheated steam, and the various vapor fractions are deposited in condensers. The thermal drying process is conducted at a temperature of 60.degree.-80.degree. C. and a pressure of 90-100 mbars. The de-watered crude product is fractionated in a film-forming evaporator and, after distillation, passes to a rectification column which condenses the low boiling constituents as the main runnings.
摘要:
A process is provided for simultaneously recovering tocopherol and sterol from a mixture containing tocopherol, fats and/or fat derivatives, more particularly fatty acids, and sterol and/or sterol derivatives, more particularly from a steamer distillate of natural oils and fats. The steps of said process comprise:free fatty acids present in the mixture are esterified with a lower alcohol, preferably methanol, 0.4 to 1.6 and more particularly 1 to 1.5 parts by volume of mixture being esterified with 1 part by volume of the lower alcohol,the mixture is subsequently transesterified with the lower alcohol in the presence of a basic catalyst,the excess lower alcohol is distilled off from the reaction mixture after the transesterification,the transesterification catalyst and the glycerol optionally present are removed, more particularly by washing,the fatty acid alkyl ester is distilled off from the mixture, more particularly after removal of the transesterification catalyst, andif desired, tocopherol and sterol are separated by methods known per se. After the transesterification reaction, the alkali catalyst is preferably neutralized with an inorganic acid and the mixture is then washed with water.
摘要:
Process for the acid-catalyzed hydrolysis of fatty acid glycerides, wherein the process is carried out continuously with the glyceride and the water being moved countercurrent to each other, and apparatus therefor.
摘要:
An improved process for purification of glycerol obtained from natural sources comprising alkalizing a glycerol-containing crude mixture in the presence of air for oxidation, evaporating the mixture in a thin-layer evaporator with redistillation of the residue, rectification and reevaporation in a packed column characterized by low-pressure-loss plates with a falling-film evaporator designed for internal and external partial condensation and to separate off unwanted constituents of the mixture, bleaching the product with activated carbon and separating the bleach in known manner.
摘要:
The invention relates firstly to a discontinuous process for conducting a heterogeneously catalyzed reaction taking place at elevated temperature, in which heat-sensitive products are formed, a heat transfer unit (4) different from the reactor (1) being used for heating and a fixed-bed catalyst (3) being used as the catalyst and the reaction mixture being continuously circulated in succession through the catalyst (3) and then through the heat transfer unit (4). The problem to be solved in this process is to avoid losses of catalyst and product and to shorten the batch time and, optionally, the reaction time in accordance with German patent applications P 38 13 612.0 and P 38 26 320.3. The invention also relates to a plant for the discontinuous heterogeneously catalyzed production of heat-sensitive products at elevated temperature comprising a reactor (1), characterized by a heat transfer unit (4) arranged outside and connected to the reactor (1), a catalyst container (3) containing a fixed-bed catalyst preceding the heat transfer unit and a pump (2) for continuously circulating the reaction mixture in succession through the catalyst (3) and then through the heat transfer unit (4).
摘要:
A process is disclosed for preparing .alpha.-branched aliphatic monocarboxylic acids with 12 to 48 carbon atoms. In a first step of the process (a), .alpha.-branched aliphatic monohydric alcohols (Guerbet alcohols) are converted in the presence of caustic alkali into the alkali salts of the corresponding .alpha.-branched aliphatic monocarboxylic acids. In a second step of the process (b), the .alpha.-branched aliphatic monocarboxylic acids are released from the alkali salts by soap splitting in the presence of an inert diluting agent.