CS245320B1 - Antifoaming agent's or antifoaming agents' mixture preparation method - Google Patents

Description

The present invention relates to a process for preparing an antifoam or a mixture of antifoams based on synthetic oxygenous organic compounds.

The process is carried out in such a way that the recovered heavy fraction from the rectification of crude 2-ethylhexanol is propoxylated at a molar ratio of 3 to 25 moles, preferably 12 to 18 moles of propylene oxide per mole of heavy fraction at 40 to 200 ° C under the catalytic effect of bases; Lewis acids.

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The invention relates to a process for the preparation of a defoamer or a blend of defoamers based on synthetic, mainly petrochemical raw materials, which makes it possible to utilize by-products from the large-scale production of higher fatty alcohols by oxoprocessing and subsequent chemical treatment.

Many types of defoamers are known, many of which are used as poly-component mixtures. Most commonly used are oxygen-containing organic compounds containing active hydrogen, such as higher fatty acids, higher fatty alcohols, hydrocarbons as well as their halogen derivatives. Significant but expensive are mainly organosilicon compounds.

According to the present invention, a process for the preparation of a defoamer or blend of defoamer based on synthetic oxygenated organic compounds is carried out in such a way that the recovered heavy fraction from the rectification of crude 2-ethylhexanol is propoxylated at a molar ratio of 3 to 25 moles, preferably 12 to 18 moles of propylene oxide. 1 mole of heavy fraction at 40 to 200 ° C under the catalytic action of bases or Lewls acids.

An advantage of the process of preparing an antifoam or antifoams according to the present invention is the raw material availability, since it can be isolated as a heavy fraction, a low-yield by-product distillation residue from the production of 2-ethylhexanol so far. Further, the fact that, after its technically feasible propoxylation, at an optimum ratio of the heavy fraction from the rectification of crude 2-ethylhexanol to propylene oxide, an antifoam is obtained with an almost twice higher antifoam efficiency compared to commercial non-silicone antifoams.

Particularly suitable heavy fractions or distillation residues from the distillation or rectification of the crude 2-ethylhexanol are suitable as heavy fractions from the production of 2-ethylhexanol. In addition to 2-ethylhexanol, the proportions also contain C12 alcohols, most of which are dodecanol and C12 diol, and usually also admixtures of acetals, esters, ether alcohols, and possibly aldehydes Ce and C12.

The propoxylation of the heavy fraction from the rectification of the crude 2-ethylhexanol is generally carried out in the liquid phase and in an inert atmosphere, under the catalytic action of bases or Lewis acids, in particular alkali metal hydroxides, optionally also alkali metal carbonates, alcoholates and the like. Propoxylation is carried out at temperatures of 40 to 200 ° C, but it is best to operate at a temperature of 130 to 150 ° C using alkaline catalysts and in the case of Lewis acids, e.g. BF 3 -etherate at 60-80 ° C. The molar ratio of heavy fractions to propylene oxide may be 1: 3 to 25, but 1: 12 to 18 is most suitable. Although other molar ratios may be used, the antifoaming performance of the antifoams thus prepared is lower. Propylene oxide may be disposable or sequential, in portions, into the propoxylation environment. For safety reasons, however, it is preferable to portion propylene oxide in portions. The propoxylation of the heavy moieties can thus be carried out batchwise, semi-continuously or continuously. However, care should be taken to maximize, virtually complete conversion of propylene oxide.

The antifoam according to the invention may be applied alone or in combination with other antifoams.

Other advantages and details of the method of the invention are apparent from the examples.

Example 1

Weigh 400 g of heavy solids from the rectification of crude 2-ethylhexanol into a 2.5 dm ³ stainless steel autoclave equipped with an anchor stirrer, duplicator and heat sink with thermometer. Crude 2-ethylhexanol is produced by aldolizing n-butyraldehyde mainly from propene oxonation, associated with dehydration of the intermediate alcohol Ce to 2-ethylhexenal and its hydrogenation on a hydrogenation catalyst (nickel on silica) at 100 to 180 degrees Celsius and a hydrogen pressure of 8 to 15 MPa . Thus, the heavy fractions are the products of simultaneous and subsequent reactions, obtained essentially as a distillation residue (86% distillate distillate as a fraction in the range of 184 to 285 ° C) from the rectification of crude 2-ethylhexanol and of the following composition:

% wt. OH = 12.9;

bromine number - 4.7 g Br / 100 g;

acid number = 0.9 mg KOH / g;

saponification number = 22.1 mg KOH / g;

2-ethylhexanol = 36.3% by weight;

alcohols, including diols C12 = 44.1% by weight;

butyraldehyde diisobutylacetal = 0.7% by weight and 7 other oxygenated organic compounds in conc. 1 to 6% by weight;

average molecular weight. = 190; density at 20 ° C = 901.9 kg / m ³ ; n _D ²⁰ = 1.4530.

Next, 3 g of potassium hydroxide are added to the autoclave and after removal of air by blowing nitrogen, 370 g of propylene oxide are further added (the molar ratio of by-products to the propylene oxide is approximately 1: 3). Thereafter, under constant stirring, the contents of the autoclave are heated to the reaction temperature of the polyaddition, with an overpressure in the autoclave of about 0.3 MPa. The polyaddition of propylene oxide to the heavy fractions from the rectification of 2-ethylhexanol is carried out at 137 + 7 ° C for 7.5 h. Completion of the polyaddition is accomplished by allowing it to react for about 1 hour with stirring and then checking for the presence of free propylene oxide.

The products obtained are tested, first, for the heavy fractions from the rectification of 2-ethylhexanol, and secondly for the propoxylation products with 3 mol of propylene oxide and applied as antifoams.

The foaming efficiency is determined by comparing the foaming capacity of the standard sample with that of the standard sample with an added defoamer. Specifically, a 100 cm ³ aqueous solution of sodium lauryl polyglycol ether sulphate with conc. Carefully pour 1 g / dm ³ into a 500 cm ³ graduated cylinder and close with a ground-glass stopper. The standard solution is foamed at 20 + 2 ° C by inverting the cylinder by 180 ° and sleeping for one minute fifty times. The height of the foam and the height of the non-foaming solution are measured 1 minute after the foaming is complete. The foaming power of the standard P _s (in percent) is calculated from the equation

P _s =. 100 in which a = height of the foam (cm), b - height of the non-foaming solution (cm).

The foaming efficiency is determined similarly, with the exception that 100 cm ^{3 of the} standard solution is added with an antifoam in an amount of 0.02 g (1 drop) and the foaming power P _o (in%) of the standard solution is determined together with the antifoam. The measurement is made in triplicate and the arithmetic mean is taken as the final result.

Thus, the liquid product of propoxylation of 1 mole of heavy fractions with 3 moles of propylene oxide obtained by the process of this example has a foaming efficiency of 57.5% and the starting heavy fractions of rectification of crude 2-ethylhexanol 56.8%.

Example 2

Propoxylation is carried out similar to Example 1, except that 760 g of propylene oxide (approximately 1: 6.2 mol) is polyaddated to 400 grams of the heavy fractions from the rectification of crude 2-ethylhexanol. The liquid product obtained has an antifoam efficiency of 65.8%.

Example 3

The procedure is similar to Example 1, but the difference is in the weight of the starting components for propoxylation. 920 g of propylene oxide (approximately 1: 10 mol) and 4 g of potassium hydroxide are weighed onto 300 g of the heavy fractions from the rectification of 2-ethylhexanol. The defoaming efficiency of the product is 72.8%. Example 4

The procedure is similar to that of Example 1, but the difference is in the weight of the starting components. Weigh 1 22-5 g of propylene oxide (approximately 1:20 mol) and 5 g of potassium hydroxide to 200 g of the 2-ethylhexanol rectification fractions. The foaming efficiency is 75.3%.

Example 5

Otherwise, in a similar manner to Example 1, 350 g of the heavy fractions from the rectification of 2-ethylhexanol with 1,600 g of propylene oxide (approximately 1: 15 mol) are propoxylated in the presence of 5 g of potassium hydroxide. The foaming efficiency of the product is 77.0%.

Example 6

Otherwise, in a similar manner to Example 1, 190 g of the heavy fractions from the rectification of 2-ethylhexanol are propoxylated with 1450 g of propylene oxide (approximately 1:25 mol) in the presence of 4 g of potassium hydroxide. The product obtained has an antifoam efficiency of 70.6%. Example 7

The procedure is similar to that of Example 5, but the propoxylation temperature is 70 + 5 ° C and 10 g of BF 3 -etherate is applied as catalyst. The foaming efficiency of the product is 77.5%.

Claims (7)

245320 5, on the one hand, heavy fractions from the rectification of 2-ethylhexanol, on the other hand, propoxyproducts thereof with 3 moles of propylene oxide and applied as defoamers. The depletion efficiency is determined by comparing the standard sample's foaming power to that of a standard sample with an added dispenser. A specific, 100 cm 3 aqueous solution of sodium lauryl polyglycol ether sulfate conc. 1 g / dm 3 is carefully poured into a 500 cm 3 metering cylinder and sealed with a carbon black plug. The standard solution is at 20 ° C + 2 ^ C overturns the cylinder by 180 ° and sleep for 1 minute fifty times. The foam height and the height of the unladen solution are measured after 1 minute after the foaming process has ended. The standard Ps (vpercent) foaming is calculated from the Ps =. 100 in which a = height of foam (cm), b - height of unsweetened solution (cm). The depletion efficiency is determined similarly except that a 0.02 g (1 drop) antifoam is added to the 100 cm 3 standard solution and the warmness (in%) of the standard solution is determined with odpeftovačom. The measurement is done in triplicate and the arithmetic mean is taken as the final result. Thus, a liquid product of 1 molar heavy propoxylation with 3 moles of propylene oxide obtained by the process of this example has a defoaming efficiency of 57.5% and a starting heavy fraction of the rectification of crude 2-ethylhexanol 56.8%. . EXAMPLE 2 Propoxylation is carried out in a similar manner to that of Example 1 except that 760 g of 8 propylene oxide (about 1: 6.2 moles) are polyaddied to 400 g of heavy portions of rectified 2-ethylhexanol. The liquid product obtained had an antifoaming effect of 65.8%. Example 3 The procedure is similar to Example 1, but the difference is in the batches of the starting components for propoxylation. To 300 g of heavy portions of 2-ethylhexanol rectification, 920 g of propylene oxide (approximately 1: 10 moles) and 4 g of potassium hydroxide were weighed. The efficacy of the product is 72.8% 4 Proceeds similar to Example 1, but the difference is in the weights of the starting components. To 200 g of heavy extracts from 2-ethylhexanol were weighed 1 22-5 g of propylene oxide (approx. 1:20 mol) and 5 g of potassium hydroxide. The depletion efficiency is 75.3 ° / o. Example Otherwise, in a similar manner to Example 1, 350 g of heavy aliquots of 2-ethylhexanol with 1600 g of propylene oxide (about 1: 15 moles) are propoxylated in the presence of 5 g of potassium hydroxide. The efficacy of the product is 77.0%. Example 6 In a similar manner to Example 1, 190 g of heavy aliquots of 2-ethylhexanol with 1,450 g of propylene oxide (about 1: 25 moles) are propoxylated in the presence of 4 g of potassium hydroxide. The product obtained has a defoaming efficiency of 70.6% The procedure is similar to Example 5, but the propoxylation temperature is 70 ± 5 ° C and the acocatalyst is applied with 10 g of BF 3 -etherate. The efficacy of the product is 77.5%. OBJECT OF THE PREPARATION OF AN EXTRACTOR OR MIXTURES COMPOSITOR BASED ON SYNTHETIC OXYGEN COMPOUNDS, WHICH IS A DERIVATIVE RECOVERY OF THE PROCESSING OF CRUDE 2-ETHYLEXHEXANOL IN THE INVENTION OF THE INVENTION the oxides per mole of heavy at 40 to 200 ° C under the catalytic action of the base or Lewis acids.