RU2326935C2 - Detergent for cleaning of metallic surface - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention is used in metallurgy industry for degreasing rolled metal products on the aggregates of continuous processing before application of different kinds of coatings (zinc, galvalume and etc.). The agent contains in g/l: sodium hydroxide 5.4-12.0, sodium carbonate 3.3-8.2, trisodium phosphate 0.6-1.25, sodium tripolyphosphate 1.0-2.5, hyrdroxyethylated alkylphenol on the basis of propylene trimer containing in a molecule 12 moles of ethylene epoxide 0.17-0.37, polyethyleneglycol esters of synthetic primary alcohol of C₁₂-C₁₄ fraction 0.14-0.23, alkylphenilpolyoxyethelenglycol acetal 0.11-0.28, chelate 0.02-0.075, defoaming agent 0.001-0.0025, water - 1 liter. Mass ratio of the blend of the organic and inorganic part of the composition to the blend of surfactants is 24.5:1. Chelate consists of disodium salt of tetrine, hydrous and trisodium salt of hydroxyetheledenediphosphonic.

EFFECT: increase of purification degree of metallic surface thanks to high cleaning capability of the composition and foam forming decrease.

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Description

The invention relates to detergent compositions and can be used in metallurgy for degreasing metal in rolls on continuous processing units before applying various types of coatings: zinc, aluminozinc, etc.

Known detergent for cleaning a metal surface containing components,%:

Oxyethylated octylphenol benzyl ester 5 Sodium hydroxide thirty Sodium carbonate thirty Sodium Metasilicate (5H ₂ O) 35

/ "Surface phenomena and surfactants." Handbook, 1984, p. 349 /.

Having a satisfactory washing ability, the composition has disadvantages. The large amount of sodium metasilicate forms a passive film on the metal surface, which subsequently has a negative effect on the formation of various coatings, which in turn leads to a deterioration in the quality of coatings.

Closest to the invention for its intended purpose and the achieved result is a detergent (RU 2134719, 08.01.98), containing the following ratio of components, g / l:

Sodium hydroxide 6.44-11.04 Sodium carbonate 5.74-9.84 Sodium metasilicate 0.42-0.72 Oxyethylated Monononylphenol based on propylene trimers containing in a molecule 12 mol of ethylene oxide 0,084-0,144 Oxyethylated Monononylphenol based on propylene trimers containing in a molecule 9 mol of ethylene oxide 0.056-0.096 Sodium Tripolyphosphate 1.26-2.16 Water The rest is up to 1 liter.

This detergent fairly well cleans metal at a temperature of 65-80 ° C and a degreasing time of 30-60 seconds, but does not give good cleaning results with high-speed processing from 4 to 12 seconds, and the high foaming rate is also a disadvantage of the product, which makes it impossible to use it on spraying units of high-speed metal processing.

The objective of the invention is to develop a detergent with high detergency, low foaming, when degreasing cold-rolled steel at high-speed spraying units (4-12 sec), continuous metal processing and the use of which does not adversely affect the formation of zinc, alumina-zinc coatings, with good performance quality.

This object is achieved in that the detergent containing sodium hydroxide, sodium carbonate, sodium phosphate trisubstituted, sodium tripolyphosphate, ethoxylated monoalkylphenol based on propylene trimers containing 12 moles of ethylene oxide in the molecule, polyethylene glycol ethers of synthetic primary alcohols fraction C ₁₂ -C ₁₄ , additionally contains acetal of alkylphenylpolyoxyethylene glycol, complex (disodium salt of ethylenediaminetetraacetic acid, aqueous or trisodium salt of hydroxyethylidene diphosphones nd acid aq) and antifoam additive is in the following ratio, g / l:

Sodium hydroxide 5.4-12.0 Sodium carbonate 3.3-8.2 Sodium phosphate trisubstituted 0.6-1.25 Sodium Tripolyphosphate 1.0-2.5 Oxyethylated Monoalkylphenol based on propylene trimers containing in a molecule of 12 moles of ethylene oxide 0.17-0.37 Synthetic polyethylene glycol esters primary alcohols fractions C ₁₂ -C ₁₄ 0.14-0.33 Alkylphenylpolyoxyethylene glycol acetal 0.11-0.28 Complexon (disodium salt of ethylenediamine tetraacetic acid, aqueous or hydroxyethylidene diphosphonic trisodium salt acid, water) 0.02-0.075 Antifoam additive 0.001-0.0025 Water The rest is up to 1 liter.

Moreover, the mass ratio of the mixture of inorganic and organic part of the composition to a mixture of surfactants is 24.5: 1.

The claimed ratio of components allows the detergent:

- provide high washing ability;

- use it on high-speed metal processing units of spray type, as working solutions have low foaming;

- use it before applying zinc and aluminozinc coatings.

The effectiveness and stability of cleaning with a washing solution is maintained when a significant amount of contamination is accumulated.

For the study, 5 detergent compositions were compiled with a different ratio of components and the composition of the known.

The detergent compositions were prepared by sequentially dissolving in warm water (35-40 ° C) for 15-20 minutes the estimated number of ingredients.

After their complete dissolution, the composition was pumped into a laboratory spray unit.

The composition of the known funds was prepared in a similar manner.

The compositions of the known and proposed detergent are shown in table 1.

The compositions of the proposed and known detergent were tested for foaming ability. The essence of the determination was that 100 cm ^{3 of} solution was poured into a standard cylinder of 250 cm ³ , closed with a stopper and shaken 20 times. After 30 seconds, the initial foam height was measured in centimeters. The determination was carried out at a temperature of 70 ° C.

The washing ability was determined by the gravimetric method, which is based on determining the percentage of washability of contaminants from the surface of a metal sample.

The tests were carried out on cold-rolled metal samples with a size of 150 × 70 mm.

Samples were thoroughly wiped twice with gasoline or white spirit, dried for 20 minutes in air, brought to a constant temperature in a desiccator, and weighed. The weighing result was recorded to the fourth decimal place.

Pure samples were contaminated with brand 20 industrial oil, dipped in an oil vessel, then suspended for 24 hours to remove excess oil.

Then the samples were weighed. The result of weighing in grams was recorded to the fourth decimal place.

The solution was heated to a temperature of 70-75 ° C in the bath spray laboratory washing facility, the pump was turned on, and contaminated samples were installed through the hole in the lid and cleaned for 4-12 sec.

After the lapse of time, the defatted samples were removed from the bath, washed with a brush, under a stream of tap water with a temperature of 60-65 ° C for 7-10 seconds and dried in an oven at a temperature of 100-110 ° C. The samples were first cooled in air and then in a desiccator to a constant temperature and weighed. The weighing results were recorded to the fourth decimal place.

The washing ability as a percentage of pollution removal from the metal surface was determined by the formula:

,

,

where A is the mass of the sample contaminated with oil, g;

B is the mass of the sample treated in the washing solution, g;

C is the mass of the sample after degreasing with gasoline or white spirit, g.

The quality of the zinc coating, the adhesion to the base, was checked by the standard method according to GOST 14019. The essence of the method was that the test sample of galvanized metal was bent 180 ° and the adhesion of the coating to the steel base was determined. With a satisfactory result, peeling of the zinc and aluminozinc coatings from the outside should not be observed. (A grid of small cracks along the entire length of the bend and peeling of the coating to a distance of not more than 6 mm from the edges of the sample is allowed).

In addition to the main test, galvanized metal samples were tested for adhesion to the base on a Lockformer device. This device formed a double bend of metal 180 ° in one plane. Bending was carried out along the entire length of the sample (not <250 mm). One sample was tested across the rolling direction, the second along. Bonding strength was assessed by visual method. There should be no exfoliation at the bend, exposing the steel surface. (A grid of small cracks is allowed).

The results of determining the indicators of foaming, washing ability and quality of the zinc coating are shown in table 2.

As can be seen from the examples (see table 2, pr. 2, 3, 4), the content of sodium hydroxide, sodium carbonate, sodium phosphate trisubstituted, sodium tripolyphosphate, ethoxylated monoalkylphenol based on propylene trimers containing in the molecule 12 moles of ethylene oxide, polyethylene glycol ethers synthetic primary alcohols of fraction C ₁₂ -C ₁₄ , acetal of alkyl phenyl polyoxyethylene glycol, complexone (disodium salt of ethylenediaminetetraacetic acid, aqueous or trisodium salt of hydroxyethylidene diphosphonic acid, aqueous) and foam box additives in the claimed range provides low foaming of the working solution, high washing ability and makes it possible to obtain further coatings with good quality indicators.

A change in the content of components below the declared limits (see table 2, pr. 1) leads to a decrease in washing ability, and the above-mentioned values lead to increased foaming of the solution and does not lead to an improvement in washing properties, but it increases the cost of the composition. In both cases, it adversely affects the quality of coatings.

Example 6 characterizes the properties of the prototype and coatings obtained after preliminary processing in this composition.

The use of the proposed detergent provides the following technical and economic advantages:

1. A high degree of cleaning of the metal surface due to the high washing ability of the composition.

2. Low consumption of funds, because detergent does not carry away with the foam.

3. Reducing production costs (manufacturability in the preparation and adjustment of the working bath) and increasing the operating time of the solution.

4. The possibility of using it in the preliminary processing of cold-rolled steel before applying zinc and aluminozinc coatings.

Table 1 No. p. Components The content in the composition, g / l one 2 3 four 5 6 * one. Sodium hydroxide 4,5 5,4 8.7 12.0 13,2 11.04 2. Sodium carbonate 2,8 3.3 5.8 8.2 9.0 9.84 3. Sodium phosphate trisubstituted 0.5 0.6 0.9 1.25 1.4 - four. Sodium Tripolyphosphate 0.9 1,0 1.7 2,5 2,8 2.16 5. Oxyethylated monoalkylphenol based on propylene trimers containing 12 moles of ethylene oxide in a molecule 0.14 0.17 0.27 0.37 0.41 - 6. Polyethylene glycol esters of synthetic primary alcohols fraction C ₁₂ -C ₁₄ 0.12 0.14 0.24 0.33 0.36 - 7. Alkylphenylpolyoxyethylene glycol acetal 0.09 0.11 0.19 0.28 0.31 - 8. Complexon (disodium salt of ethylenediaminetetraacetic acid, aqueous or trisodium salt of hydroxyethylidene diphosphonic acid, aqueous) 0.015 0.02 0,048 0,075 0.1 - 9. Antifoam additive 0,0009 0.001 0.0018 0.0025 0.003 - 10. Oxyethylated monononylphenol based on propylene trimers containing 12 mol of ethylene oxide in a molecule - - - - - 0.144 eleven. Ethoxylated monononylphenol based on propylene trimers containing 9 mol of ethylene oxide in a molecule - - - - - 0,096 12. Sodium metasilicate - - - - - 0,072 13. Water Up to 1 liter fourteen. The ratio of the mixture of inorganic and organic parts of the composition to a mixture of surfactants 24.5: 1 24.5: 1 24.5: 1 24.5: 1 24.5: 1 -

table 2 Detergent composition The mass of samples fried with oil (A), g The mass of samples fat-free in a washing solution (B), g The mass of samples defatted with gasoline or white spirit (C), g Washing ability,% Foaming ability, cm Quality indicators of zinc and aluminozinc coatings (adhesion strength at bending by 180 ° and on the Lockformer device) one. 17,97140 17,96885 17,96855 89.5 0.7 Not satisfactory 2. 17,67175 17,66863 17,66860 99.0 1,2 Satisfactorily 3. 17,05110 17, 04673 17,04670 99.3 1.25 Satisfactorily four. 17,49570 17.49327 17.49325 99,2 1.3 Satisfactorily 5. 17,24130 17,23850 17,23840 96.6 2.6 Not satisfactory 6 * 17,67900 17,67610 17,67545 82.7 3,5 Not satisfactory

Claims (1)

Detergent for cleaning a metal surface containing sodium hydroxide, sodium carbonate, sodium phosphoric acid trisubstituted, sodium tripolyphosphate, ethoxylated monoalkylphenol based on propylene trimers containing 12 moles of ethylene oxide in a molecule, polyethylene glycol ethers of synthetic primary alcohols of fraction C ₁₂ -C ₁₄ , antifoam additive, characterized in that it additionally contains acetal of alkyl phenylpolyoxyethylene glycol, complexone - ethylenediaminetetraacetic acid disodium salt, aqueous or hydro sietilidendifosfonovoy acid trisodium salt water in the following ratio, g / l: sodium hydroxide 5.4-12.0 sodium carbonate 3.3-8.2 trisubstituted sodium phosphate 0.6-1.25 sodium tripolyphosphate 1.0-2.5 ethoxylated monoalkylphenol based on propylene trimers containing in a molecule of 12 moles of ethylene oxide 0.17-0.37 synthetic glycol ethers primary alcohols fractions C ₁₂ -C ₁₄ 0.14-0.33 alkylphenylpolyoxyethylene glycol acetal 0.11-0.28 complexon 0.02-0.075 antifoam additive 0,0009-0,0025 water the rest is up to 1 liter moreover, the mass ratio of the mixture of inorganic and organic part of the composition to a mixture of surfactants is 24.5: 1.