SU187917A1 - METHOD OF WASHING METAL PRODUCTS - Google Patents

Description

The method of washing metal products from fatty and saline contaminants using aqueous solutions of anionic surfactants is known. However, the use of these compounds causes corrosion of the metal surface.

In order to eliminate this drawback, it is proposed to use alkenyl succinic acid mono- or polyglycerides as a surfactant.

R-CH-COOH I SNg - COOY,

where R is alkenyl with the number of carbon atoms from 8 to 18, X is the residue of glycerol, polyglycerol and the residue of the monoester of noliglycerol and alkenyl succinic acid, Y is the residue of glycerol, polyglycerol, the residue of the monoether of polyglycerol and alkenyl succinic acid or alkali metal.

The following derivatives of alkenyl succinic acids, which contain both non-ionic and anionic active substances, have the most effective combination of detergent and protective properties with respect to metals.

groups, giving high adsorption properties to substances:

R -CHSOO (CH2CHONSN2O) „H

(I)

SNgSOO (СН2СНОНСН2О) „Н

SNGOOMe

10 R -CHSOO (СН2СНОНСН2О) „ОССН - Н

(AND)

SNaOCOO (СН2СНОНСН20) „ОSSN -R

SNGSOOMe, R - SNSIN SNONSN20N

(Iii)

SNGOOMe

20 where R - Cs - Cis, Me - alkali metals, 2 n - not less than 4.

Mono- and polyglycerides of alkenyl succinic acids are obtained by known methods — esterification or polyesterification of alkenyl succinic anhydrides, and these anhydrides — by alkylation of maleic anhydride with mixtures of olefins (propylene polymerization products) or butylenes (cracking gases and

Alkenyl glycerides of itoric acids are introduced into the washing solutions in an amount of from 20 to 50 g per 1 ,, -D; ® ® | No.. "Details are completely washed from; s 1 / r; th toyeny and further do not corrode ..,.

Unlike sodium oleate, which leaves thick color films on the washed surface, alkenyl succinic acid glycerides form very thin invisible adsorption films on the surface of metals.

Example 1. Metal parts contaminated with mechanical impurities, fats and then hands are washed in an aqueous solution containing 20-50 g / u of alkenyl succinic acid polyglycerides {I) with an average mol. at. 870. Parts are completely laundered from contamination.

Completeness of washing is controlled by the gravimetric method with an accuracy of up to 1 10 g and according to the degree of wetting of the surface. Washed parts are stored in the atmosphere of a chemical laboratory (air humidity 70-90%) for 25 days, after which they are removed from the tests without signs of corrosion.

Control details, washed in sodium oleate solution (25 g / l) and stored under the same conditions, begin to corrode in the first day.

Example 2. According to the procedure of Example I, contaminated parts are washed in a solution of 20 U / L of polyglyceride bis-monoether of alkenyl succinic acids (I) with an average mol. at. 1350.

Parts are completely washed. They are stored for 1 month, after which they are removed from tests without signs of corrosion.

Example 3. According to the procedure of Example 1, contaminated parts are washed in a solution of 20 g1l of monken alidel succinic acid (II) monogliderides with an average mol. at. 350. Parts are completely washed. They are stored for 1 month, after which they are removed from testing without

signs of corrosion.

Subject invention

A method of washing metal products with the aid of aqueous solutions of surfactants, characterized in that, in order to prevent corrosion of the metal surface, mono- or polyglycerides of alkenyl succinic acids of the general formula are used as surfactants

R - SP - SOOH

SPA - COOY,

where R is alkenyl with the number of carbon atoms from 8 to 18, X is the residue of glycerol, polyglycerol, and the residue of the monoester of polyglycerol and alkenyl succinic acid, Y is the residue of glycerol, polyglyderol, the residue of the monoether of polyglycerol and alkenyl succinic acid or alkali metal.