RU2387706C1 - Detergent for cleaning metal surfaces - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention can be used to wash off oil contaminants in washing machines during interoperational cleaning, for cleaning surfaces in hard-to-reach places, microcracks, surfaces damaged with metal loss from oxide scales and rust. The detergent contains the following in wt %: sodium carbonate peroxy solvate Na₂CO₃·1.5H₂O₂ 5-8, sodium silicofluoride Na₂SiF₆ 2-3.5, potassium chromate K₂CrO₄ - 3-4.5, water - the rest.

EFFECT: increased ability of cleaning hard-to-reach places and microcracks, increased ability of cleaning off oxide scales and rust with anticorrosion protection of the cleaned surface.

1 tbl, 3 ex

Description

The invention relates to the field of detergent compositions for cleaning metal surfaces of equipment parts and machines from oil, oil products and their decomposition products and can be used in washing operations from oil pollution in washing machines during interoperative cleaning, for cleaning surfaces in hard to reach places, microcracks, surfaces, damaged with loss of metal from scale and corrosion.

Known detergent for cleaning containers and metal surfaces from oil, oil products and oils, described in the patent of the Russian Federation No. 2171831, published in 1995, containing (in wt.%): A water-soluble salt of alkali metals 50-94, nonionic surfactant 3-20, sodium salt of polyacrylic acid, modified with ether groups 1-8, corrosion inhibitor 0.5-15, dispersant 1-5, antifoam 0.1-1, water the rest.

The disadvantages of this detergent are insufficient environmental friendliness of the product, the high temperature of the aqueous solution for washing, which must be maintained during washing, which is impossible, that is, this detergent has low performance when used for industrial purposes.

The detergent is known, described in the application for invention of the Russian Federation No.2000125411, published March 10, 2000, containing caustic soda, sodium tripolyphosphate, soda ash, sodium metasilicate, ethoxylated monoalkylphenol based on propylene trimers, containing 12 mol of ethylene oxide ethylene ethylene olio in the molecule based on triplen triplene containing 6 mol of ethylene oxide in the molecule in the following ratio of components (in wt.%): caustic soda 0.9-3.3, sodium tripolyphosphate 0.72-2.64, soda ash 2.82-10, 34, metasilic t of sodium 0.6-2.2, ethoxylated monoalkyl phenol based on propylene trimers containing 12 mol of ethylene oxide in the molecule 0.024-0.088, ethoxylated monoalkyl phenol based on propylene trimers containing in the molecule 6 mol of ethylene oxide 0.036-0.132, trisodium phosphate 0, 84-3.08, polyoxyethylene glycol esters of synthetic primary higher fatty alcohols of the C ₁₆ -C ₂₀ fraction 0.06-0.22, the rest is water. The working temperature of the solution is 50-80 ° C.

The disadvantages of this detergent are insufficient environmental friendliness of the product, the high temperature of the aqueous solution for washing, which must be maintained during the washing process, which is impossible, in addition, insufficient efficiency when cleaning metal surfaces from contamination in hard-to-reach places and microcracks, in places of scale and corrosion, insufficient efficiency when cleaning metal surfaces from scale and corrosion, insufficient corrosion protection of the surface being cleaned, as a result of which the external this type of metal surface does not produce a sufficiently clean impression and very quickly re-deposition of contaminants on the surface to be cleaned, especially in places of scale and corrosion, even during direct cleaning, that is, this detergent has low performance when used for industrial purposes.

The closest analogue selected as a prototype is the patent for the invention of the Russian Federation No. 2247770, published March 10, 2005. The detergent for cleaning metal surfaces described in the patent contains a degreasing composition and water, as a degreasing composition it contains a composition of sodium carbonate peroxysolvate Na ₂ CO ₃ · 1,5H ₂ O ₂ , and sodium silicofluoride Na ₂ SiF ₆ , and water in the following ratio of components, wt.%: Sodium carbonate peroxysolvate Na ₂ CO ₃ · 1,5H ₂ O ₂ - 2.0- 3.5, sodium silicofluoride Na ₂ SiF ₆ - 2.0-3.5, the rest is water.

This detergent is environmentally friendly and provides the washing of metal surfaces from contamination at a temperature of 20-22 ° C.

The disadvantages of this detergent are insufficient efficiency when cleaning metal surfaces from contamination in hard-to-reach places and microcracks, in places of scale and corrosion, insufficient efficiency when cleaning metal surfaces from scale and corrosion, insufficient anti-corrosion protection of the surface being cleaned, as a result of which the appearance of the metal surface does not produce a sufficiently clean impression and very quickly re-deposition of contaminants on the surface to be cleaned especially in places of scale and corrosion, even during direct cleaning, that is, this detergent has low performance when used for industrial purposes.

The objective of the invention is the creation of a new detergent for cleaning containers and metal surfaces, with high performance when used for industrial purposes: environmentally friendly, low temperature aqueous solution, with high cleaning ability from contamination in hard to reach places and microcracks, in places of scale and corrosion , with high cleaning ability from scale and corrosion, with corrosion protection of the surface being cleaned.

The technical problem is solved by the creation of a detergent for cleaning a metal surface containing a degreasing composition of sodium carbonate peroxysolvate Na ₂ CO ₃ · 1,5H ₂ O ₃ and sodium silicofluoride Na ₂ SiF ₆ , and water, according to the invention with an additional content of corrosion inhibitor, potassium chromate K ₂ GrO ₄ in the following ratio of components, wt.%: Sodium carbonate peroxysolvate Na ₂ CO ₃ · 1,5Н ₂ O ₂ - 5.0-8.0, sodium silicofluoride Na ₂ SiF ₆ - 2.0-3.5 , K ₂ CrO ₄ - 3.0-4.5, the rest is water.

Due to the fact that the detergent for cleaning the metal surface additionally contains a corrosion inhibitor - potassium chromate K ₂ CrO ₄ in the following ratio of components, wt.%: Sodium carbonate peroxysolvate Na ₂ CO ₃ · 1,5Н ₂ O ₂ - 5.0- 8.0, sodium silicofluoride Na ₂ SiF ₆ - 2.0-3.5, K ₂ CrO ₄ - 3.0-4.5 the rest of the water, get a detergent with high performance when used for industrial purposes: environmentally friendly, with a low temperature of an aqueous solution, with a high cleaning ability from pollution in hard to reach places and microcracks, in places of scale and corrosion, with a high cleaning ability of scale and corrosion.

At the filing date, in the opinion of the authors and the applicant, the claimed detergent is unknown and this decision is new.

The inventive combination of essential features exhibits a new property, which allows to obtain a technical result.

The action of the introduced substance in the form of Na ₂ СО ₃ · 1,5 Н ₂ О ₂ consists in the fact that when water gets into water, hydrogen peroxide decomposes according to the equation:

Na ₂ CO ₃ · 1.5H ₂ O ₃ → Na ₂ CO ₃ + 1,5H ₂ O ₂

2H ₂ O ₂ → 2H ₂ O + O ₂ ↑

and the oxygen formed in the aqueous solution creates a cavitation effect, in connection with which the washing effect is achieved at low temperatures, at the same time, hydrogen peroxide is a corrosion stimulator and the addition of a corrosion inhibitor K ₂ CrO ₄ - 3.0-4.5 neutralizes this effect and inhibits the corrosion process, enhances the anti-corrosion properties of the compound, cleansing the surface of various contaminants, at the same time cleans the surface and microcracks of scale and corrosion, does not allow them to develop further, heals the “wounds” of cracks, together with scale and corrosion, removing residual contaminants from the surface and from inaccessible places.

The optimum content in the mixture with water is sodium carbonate peroxysolvate Na ₂ CO ₃ · 1.5H ₂ O ₂ - 5.0-8.0, sodium silicofluoride Na ₂ SiF ₆ - 2.0-3.5, potassium chromate K ₂ CrO ₄ - 3.0-4.5. When going beyond the limits of improving the washing properties does not occur.

Improving the environmental friendliness of the product is achieved due to the formation of sparingly soluble metal fluoride complexes and sorption of oil products on S _i O ₂ formed during the hydrolysis of cremnefluoride. When using an aqueous solution of the product, an alkaline medium is formed in which sodium silicofluoride dissociates into ions to form F ^- . Fluoride ion in solutions is hydrolyzed and is capable of forming numerous stable fluoride complexes of various metals. The release of oxygen bubbles contributes to the loosening of contaminants on the surface of the metal. Minerals reduce the surface tension of petroleum products on the metal surface, formed as a result of hydrolysis of SiO ₂ cremnefluoride adsorbs petroleum products from the washed surface. The resulting poorly soluble complex compounds of fluorine with a metal in a monolayer are removed during washing.

The spent cleaning solution is used as mixing water in the production of building materials as a hardening retardant and an acid-resistant agent.

Given the foregoing, we can conclude that the proposed composition of the detergent for cleaning a metal surface does not explicitly follow from the prior art and the whole set of essential features exhibits a new property that allows to achieve the specified technical result, that is, the invention meets the eligibility criterion - "inventive step".

The claimed invention meets the criterion of "industrial applicability", as it can be used in the national economy when cleaning oil-contaminated metal surfaces.

Example 1

The technological scheme for the production of detergent for cleaning metal surfaces consists of the following stages:

1. Dose peroxysolvate sodium carbonate Na ₂ CO ₃ · 1,5N ₂ O ₃ - 5.0;

2. Dose sodium silicofluoride Na ₂ SiF ₆ - 2.0;

3. Dose potassium chromate K ₂ CrO ₄ - 3.0;

4. All components are mixed in a mixer in the presence of water - 90.0 for 3 minutes;

5. Measure the temperature of the mixture. It should be 20-22 ° C.

Example 2

The technological scheme for the production of detergent for cleaning metal surfaces consists of the following stages:

1. Dose peroxysolvate sodium carbonate Na ₂ CO ₃ · 1,5N ₂ O ₂ - 8.0;

2. Dosage of sodium silicofluoride Na ₂ SiF ₆ - 3.5;

3. Dose potassium chromate K ₂ CrO ₄ - 4,5;

4. All components are mixed in a mixer in the presence of water - 84.0 for 3 minutes;

5. Measure the temperature of the mixture. It should be 20-22 ° C.

Example 3

The technological scheme for the production of detergent for cleaning metal surfaces consists of the following stages:

1. Dose peroxysolvate sodium carbonate Na ₂ CO ₃ · l, 5H ₂ O ₂ - 6.5;

2. Dosage of sodium silicofluoride Na ₂ SiF ₆ - 2.75;

3. Dose potassium chromate K ₂ CrO ₄ - 3.75;

4. All components are mixed in a mixer in the presence of water - 87.0 for 3 minutes;

5. Measure the temperature of the mixture. It should be 20-22 ° C.

Testing the washing ability of the composition was carried out at a concentration of the working solution of 15, 25, 35 g / l and a temperature of 20-22 ° C. The quality of cleaning a contaminated surface should be determined by the gravimetric method (Kozlov, Yu.S. Cleaning products in mechanical engineering. - M .: Mashinostroenie, 1982. - 261 p.) On a balance of at least class 2. See table 1 from the test report, the recommended concentration is 25 g / l.

The concentration of the working solution of 15 g / l does not provide a sufficient degree of cleaning from scale, corrosion and contamination, the concentration of the working solution of 35 g / l gives the degree of purification the same with the concentration of the working solution of 25 g / l, with a higher consumption of detergent. Therefore, the recommended concentration is 25 g / l.

When using the weight method, the quality of cleaning a metal surface is determined as a percentage of the mass of removed contaminants to the mass of the initial values:

where q ₁ is the mass of the contaminated sample, mg;

q ₂ is the mass of the sample subjected to purification, mg;

q ₃ is the mass of the pure sample, mg.

The washing ability, the ability to clean from oxides and corrosion (hereinafter the washing ability), was determined by the gravimetric method, the essence of which is to determine the washability of contaminants, oxides, and traces of corrosion from the surface of the samples. The samples are washed in a laboratory washing installation by dipping with the excitation of the washing solution using a mixer having a constant speed of 3000 rpm. The total concentration of detergents in the working solution is 7 g / dm ³ (i.e., a working solution of 0.7% concentration), the washing temperature is from 45 to 98 ° C, most of the experiments were carried out at a temperature of 75 ° C. For testing, take two identical samples No. 1 and No. 2, made of steel grade St-3 with traces of oxides and corrosion visually detectable, washed with running water, acetone, dried and weighed on an analytical balance. Further, sample No. 1 pollutes the paraffin deposits from real oil production facilities (tubing, submersible pump elements, etc.) by dipping into the melt or polluting the surface of the sample with graphite lubricant. Contaminated sample No. 1 is cooled at room temperature, weighed and placed in a washer, where it is washed for 3 minutes. After washing, sample No. 1 is dried in air to constant weight. Washing ability is defined as the ratio of the mass of contaminants washed off from the surface of the test sample No. 1 to the total mass of contaminants on its surface before washing, expressed as a percentage. The washing ability was determined at different temperatures of the working solution, as well as at different salinity of the water used to prepare the working solution (with a low degree of mineralization of 4.5 ppm and a high degree of mineralization of 45 ppm, which was obtained by dissolving natural sea salt in a given amount of distilled water) . The cleaning ability of oxides and corrosion is determined by visually comparing sample No. 1 with sample No. 2, which was not subjected to washing.

In addition, to determine the anticorrosive ability of the inventive detergent, sample No. 1 washed by the inventive agent and sample No. 2 with previous traces of oxides and corrosion are left under the influence of the external environment and daily wetting with water for 5 days. On sample No. 1, traces of oxides and corrosion did not appear by the end of the fifth day; on sample No. 2, the area covered by oxides and corrosion increased 1.5 times.

The test results are listed in table 1.

Table 1 The content of components, wt.% Temperature ° C % washing of petroleum products (pure machine oil) % descaling and corrosion Na ₂ CO ₃ · 1,5H ₂ O ₂ 5,0 Na ₂ SiF ₆ 2.0 K ₂ CO ₄ 3.0 twenty 98.3 98.5 water rest up to 100 Na ₂ CO ₃ · 1.5H ₂ O ₂ 8.0 Na ₂ SiF ₆ 3,5 K ₂ CO ₄ 4,5 twenty 99.0 99.0 water rest up to 100 Na ₂ CO ₃ · 1.5H ₂ O ₂ 6.5 Na ₂ SiF ₆ 2.75 twenty 98.2 98.3 K ₂ CO ₄ 3.75 water rest up to 100 PROTOTYPE Na ₂ CO ₃ · 1,5H ₂ O ₂ 2.0-3.5 Na ₂ SiF ₆ 2.0-3.5 twenty 95.0-97.0 10.0 water rest up to 100

An analysis of the data in the table shows that the proposed detergent for cleaning a metal surface has high performance characteristics when used for industrial purposes: an environmentally friendly, low-temperature aqueous solution, with a high cleaning ability from contamination in hard-to-reach places and microcracks, in places of scale and corrosion, with a high cleaning ability from scale and corrosion, due to the fact that the detergent for cleaning a metal surface additionally contains an inhibitor orrozii - potassium chromate K ₂ CrO _4, with the following component ratio, wt.%: peroksisolvat sodium carbonate Na ₂ CO ₃ · 1.5H ₂ O ₂ - 5.0-8.0, sodium fluorosilicate Na ₂ SiF ₆ - 2.0 -3.5, K ₂ CrO ₄ - 3.0-4.5, the rest is water.

Claims (1)

Detergent for cleaning a metal surface containing a degreasing composition of sodium carbonate peroxysolvate Na ₂ CO ₃ · 1,5H ₂ O _2, sodium silicofluoride Na ₂ SiF ₆ and water, characterized in that it additionally contains a corrosion inhibitor - potassium chromate K ₂ CrO ₄ at the following ratio of components, wt.%: peroxysolvate of sodium carbonate Na ₂ O ₃ · 1.5H ₂ O ₂ 5.0-8.0, sodium silicofluoride Na _z SiF ₆ 2.0-3.5, K ₂ CrO ₄ 3, 0-4.5, the rest is water.