摘要:
The invention is a process for the continuous liquid-phase esterification of C.sub.2 -C.sub.24 fatty acids with alkanols in countercurrent contact and reaction in a reaction column, the catalysts and fatty acids are introduced at the top plate and the alkanols below the lowest plate, at a head pressure of the reaction column of 200 to 900 hPa. The process reduces dehydration of the alkanols.
摘要:
A process for the continuous transesterification of C.sub.6 -C.sub.22 fatty acid lower alkyl esters, particularly methyl esters, with polyhydric C.sub.2 -C.sub.5 alcohols, particularly glycerol, in a reaction column comprising a rectifying and reaction section, alkaline catalysts and polyhydric alcohol are introduced into the upper part of the reaction column and boiling fatty acid methyl ester is introduced into the middle part of the reaction column. The product collected in the sump of the column is removed, heated and returned to the lower part of the reaction column. Product is removed from the sump. Lower alkanols passing from the reaction column section to the rectifying section are rectified. The reaction column is operated in boiling equilibrium in its lower part and predominantly in an absorption/desorption equilibrium in its upper part.
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.
摘要:
The epoxidation of terminally and/or internally olefinically unsaturated hydrocarbon compounds which are liquid at 50.degree. to 100.degree. C. and at atmospheric pressure (oil phase), in which the oil phase is treated with an acid phase containing acetic acid, hydrogen peroxide and peracetic acid in aqueous solution, after which the aqueous acid phase is separated from the oil phase, the peracetic acid in the aqueous acid phase is regenerated and the regenerated aqueous acid phase is returned to the epoxidation reactor. Epoxidation is carried out using an aqueous acid phase containing at most about 10% by weight of peracetic acid, and the peracetic acid content in the aqueous acid phase is reduced by at most about 50%, based on the peracetic acid content of the aqueous acid phase used, after a single passage through the epoxidation stage. After separation from the oil phase, the aqueous acid phase preferably is cooled before regeneration.
摘要:
A process for the production of solid or paste-form products by fast reactions is carried out stoichiometrically wherein a gaseous medium is introduced into each of the reactants to be reacted with one another, the reactant streams formed are combined and are subsequently forced through a spray unit in a weight ratio of gaseous medium to product stream of from 0.04 to 0.3 (kg/kg) and at a rate of 0.1 to 15 m/second, as calculated from the gas-free reactant streams and based on the free cross-section of the spray unit. The products obtained are free from readily volatile constituents.
摘要:
A process for preparing diglycerol in high concentrations and high yields by partially reacting glycerol in the presence of an alkaline catalyst to form a reaction mixture containing from 10 to 15% by weight of diglycerol and separating the unreacted glycerol from the reaction mixture in a wiped film or short path first distillation zone at a reduced pressure of 0.5 to 5 mbar and distilling a bottoms product from the first distillation zone in a second distillation zone which is a short path distillation zone at a pressure of 0.05 to 0.3 mbar to obtain a second bottom product containing at least 90% by weight diglycerol. Diglycerol of higher purity can be obtained by recovering diglycerol as a distillate from a third distillation zone.
摘要:
The invention relates to a continuous process for the production of lower alkyl esters at temperatures of up to 100.degree. C. and under pressures of up to 10 bar by reaction of fatty acid triglycerides containing less than 1% free fatty acid with a lower alcohol in two stages in the presence of a homogeneous alkaline catalyst, the glycerol formed being removed after the first stage. To enable the process to be carried out with high yields and with lower maintenance, investment and energy costs than in the prior art, the reaction mixture is passed through a reactor and a following static separator only once in each stage, tube reactors are used as the reactors and the Reynolds number of the flow of the reaction mixture is greater than 2,300.
摘要:
A process for the production of fatty ketones by pyrolysis of fatty acid magnesium salts wherein fatty acids corresponding to formula (I):R.sup.1 COOH (I)in which R.sup.1 CO is an aliphatic acyl radical containing 12 to 22 carbon atoms and 0, 1, 2 or 3 double bonds, are heated to temperatures of 320.degree. to 360.degree. C. in the presence of magnesium oxide and the fatty ketones formed are distilled off from the reaction mixture under reduced pressure.
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.