CS245302B1 - A method for obtaining an antifoam or antifoam mixture - Google Patents

Abstract

The solution relates to a method for obtaining a defoamer or a mixture of defoamers based on synthetic oxygenated organic compounds. The method is carried out by obtaining it by isolation as a heavy fraction from the rectification of crude 2-ethylhexanol with a boiling point above 184 °C.

Description

The present invention relates to a method for obtaining, resp. preparation of an effective antifoam based on synthetic, mainly petrochemical raw materials, while allowing the use of by-products from large-scale production of higher fatty alcohols by oxoprocesses.

Many substances are known from industrial practice as well as from the literature, generally poly-component mixtures which are effective as antifoams. It is known to use oxygen-containing organic compounds containing active hydrogen as higher fatty acids, higher fatty alcohols, hydrocarbons, as well as their halogen derivatives. Organosilicon compounds are particularly important but expensive. Technically available include the products of oxyethylation of abietic acid and oleic acid, respectively. tall oil oxyethylation as well as ethoxylation or propoxylate products of 4 to 25 carbon atoms with 1 to 25 moles of alkylene oxide alone, or more often in combination with organosilicon compounds (U.S. Patents 2,991,248, 3,235,501 and 3,235,502). They are then at least partially esterified polyols, e.g. esterified glycerol, pentaerythritol and sorbltol (U.S. Pat. No. 3,235,498), and an unsaturated acid defoamer such as acrylic and methacrylic acid (U.S. Pat. No. 3,458,567). Relatively widespread are antifoams based on poly-component blends (U.S. Pat. Nos. 2,923,687, 3,180,836 and US Patent 183,982), in which the major components are higher fatty acids, vegetable and mineral oils, and polyaddition products of alkylene oxides to higher fatty acids, or alcohols. Their advantage is nontoxicity, but the drawback is relatively lower antifoaming efficiency. In the case of organosilicon components, such as silicone oils, the high antifoam efficiency (even above 90%) is remarkable, but the shortage is in their raw material and energy intensity. However, the present invention solves these problems to a remarkable extent.

According to the present invention, a process for obtaining a defoamer or a blend of defoamer based on synthetic oxygenated organic compounds is carried out by isolation as a heavy fraction from the rectification of crude 2-ethylhexanol having a boiling point above 184 ° C.

An advantage of the method of obtaining an antifoam according to the present invention is the raw material availability when it can be isolated as a heavy fraction, so far ¹ low-valued byproduct - a distillation residue from the production of 2-ethylhexanol.

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

Further advantages and details of the method of the invention are apparent from the example.

Example 1

The heavy fractions obtained essentially as a distillation residue from the rectification of crude 2-ethylhexanol of the composition:% by weight. 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; hutyraldehyde diisobutyl acetate = 0.7 wt. and 7 other oxygenated organic compounds in conc. 1 to 6% by weight; average molecular weight = 190; density at 20 ° C = 901.9 kg. nr ³ ; η ₀ 2θ = 1.4530.

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 of 1 g / dm ³ is carefully poured into a 500 cm ³ graduated cylinder and sealed with a ground-glass stopper. The standard solution is foamed at 20 + 2 ° C by inverting the cylinder by 180 ° and sleeping for 1 min. The height of the foam and the height of the non-foaming solution are measured 1 minute after the foaming is complete. Foaming standard P _s (in%) g

is calculated from the relation P _s - —-—. 100, in which a = the height of the foam (cm), b - the height of the non-foamed solution (cm).

The foaming efficiency is determined similarly, except 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.

Heavy fractions from the rectification of crude 2-ethylhexanol had antifoaming efficacy

Claims (1)

SUMMARY OF THE INVENTION A method for obtaining an antifoam or antifoam composition based on synthetic oxygenated organic compounds, characterized in that it is recovered by isolation as a heavy fraction from the rectification of crude 2-ethylhexanol with a boiling point above 184 ° C.