RU2635266C1 - Anti-ice reagent for transport equipment - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: in the method, the alkaline run of caprolactam production is modified by treating it with cyclic polydimethylsiloxane in an amount of 6.0 wt % or dimethylsiloxane in an amount of 9.0 wt %, or hexamethyldisiloxane in an amount of 8.0 wt %, or a dimethylsiloxane copolymer with diphenylsiloxane in an amount of 6.0 wt %.

EFFECT: production of anti-ice reagent for transport equipment characterized by low freezing temperatures and low content of modifying additives.

5 cl, 1 tbl, 4 ex

Description

The invention relates to chemical compositions for coating the metal surfaces of dump cars, open wagons and other mining and transport equipment against freezing and sticking of overburden, coal, iron ore and other wet bulk materials to them at an ambient temperature of -75 ° C and can be used in the mining industry: mining of coal, metal ores, non-ferrous metal ores, limestone, chalk, clay.

An urgent problem of the mining industry is the transportation of coal and iron ore by rail. Low subzero temperatures in winter, typical of the Russian Federation, necessitate the use of antifreeze reagents for coating metal surfaces of cars and other transport and mining equipment in order to prevent freezing of shipped products to metal surfaces at subzero temperatures.

At present, various antifreeze reagents are widely used in industrial practice: 1) waste or oil products (severin, niogrin, universin, etc.); 2) polyhydric alcohols (ethylene glycol, glycerin), polyols and their water-soluble esters; 3) salts of inorganic acids (calcium and magnesium chlorides); 4) salts of organic acids - acetates, formates. In the last group of reagents, special attention is paid to the use of caprolactam production wastes, namely, the alkaline runoff of caprolactam production (SCSPC), which is an aqueous solution of salts of organic acids.

A patent search revealed the presence of a number of technologies for producing anti-icing reagents used in the processing of transport equipment based on waste from chemical industries.

So, the antifreeze reagent is known, described in USSR author's certificate No. 1113568 (publ. September 15, 1984), which includes an aqueous solution of sodium salts of adipic acid - a waste in the process of producing cyclohexanone by oxidation of cyclohexane (alkaline stock of caprolactam production).

Also known is the composition of the anti-icing reagent (USSR author's certificate No. 1373713, publ. 02.15.1988), which includes an aqueous solution of sodium salts of adipic acid - waste in the process of producing cyclohexanone by oxidation of cyclohexane (alkaline stock of caprolactam production) and an aqueous solution of sodium salts of hydrochloric and sulfuric thiosulfuric acid is a by-product of the synthesis of isopropylphenylparaphenylenediamine - diaphen "FP".

The composition described in USSR author's certificate No. 1680750 (publ. 09/30/1991) is obtained by mixing an aqueous solution of sodium salts of adipic acid - waste in the process of producing cyclohexanone by oxidation of cyclohexane (alkaline effluent from caprolactam) and an aqueous acidic effluent from mono-based cyclohexanone and dicarboxylic acids. However, the described compositions are not resistant to delamination - at an ambient temperature below minus 10-15 ° C, sedimentation begins, in addition, the pour point is not lower than minus 30 ° C, which is not enough for processing wet bulk materials in the winter.

Also known is the antifreeze reagent (RU patent 2486223, publ. 06/27/2013), which includes an aqueous solution of sodium salts of carboxylic acids - an alkaline stock of caprolactam production and an additive that reduces the pour point and prevents delamination, which can be used as ethyl alcohol, isopropyl alcohol, ethyl alcohol head fraction, methanol-ether-aldehyde fraction (MAEF), methyl alcohol, 2-methyl-propanol, isoamyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, monoethyl Marketing ether, potassium acetate, sodium acetate, potassium formate, sodium formate, calcium chloride, magnesium chloride, sodium chloride. This invention solves the problem of separation of the composition at low temperatures and allows to obtain an antifreeze reagent with a pour point below minus 50 ° C.

However, the described composition does not allow to create a uniform and flexible film on the metal surfaces of cars that prevents freezing of the transported cargo, capable of maintaining the integrity of the structure when exposed to bulk cargo weighing up to 60-66 tons. Also, the described composition is not characterized by a high degree of wetting of coal and other hydrophobic materials, which leads to a low uniformity of the created film and an increase in the consumption of antifreeze reagent. In addition, to obtain a non-delaminating composition with a pour point below minus 50 ° C, it is necessary to introduce an additive that reduces the pour point and prevents delamination, in an amount up to 50%, which leads to a significant increase in the price of the finished antifreeze reagent.

The prior art prophylactic against freezing and freezing of coal, overburden during transportation and storage (RU patent 2564349, publ. 09/27/2015) based on obtained in the production of caprolactam by oxidation of cyclohexane aqueous solution of sodium salts of carboxylic acids, containing a multifunctional additive of nonionic surfactant - a mixture of butyl ethers of propylene glycols of the general formula C ₄ H ₉ O [CH ₂ CH (CH ₃ ) O] _n H, where n = 2-4 in an amount of 0.05-1.00%. The known composition provides a reduction in surface tension, the creation of a uniform coating with a lower consumption of reagent per 1 m ² , the reduction of freezing and freezing of coal, overburden rocks, a decrease in the strength of ice and ease of unloading. As a disadvantage of this invention should be recognized a high freezing point (minus 28-43 ° C), which limits the scope of the proposed tool.

The closest in technical essence to the claimed invention (prototype) is an antifreeze reagent (patent RU 2550186, publ. 05/10/2015) against freezing, sticking, freezing in bulk and dusting of bulk materials containing alkaline stock production of caprolactam (85-99%) and additive, glycerin (1-15%) is used as an additive. Variants of an antifreeze reagent against freezing, sticking, freezing in mass and dust formation of wet bulk materials are also proposed, where the additive contains acetic acid and / or low molecular weight forest chemical (1-5%) or glycerin (1-15%) and acetic acid and / or low molecular weight wood-chemical acids (1-5%). The research results showed that the introduction of the described composition of glycerol and / or glycerol-containing product from 1 to 30 wt. % (according to the first embodiment), acetic acid and / or products containing, for example, acetic acid from 1 to 20 wt. % (in the second embodiment), or a mixture of glycerol and / or glycerin-containing product from 1 to 20 wt. % and acetic acid and / or products containing acetic acid and / or acid from a number of organic and inorganic acids, readily soluble in water, the sodium salts of which are also readily soluble in water, from 1 to 20 wt. % (according to the third option), leads to a decrease in the pour point of the finished product to minus 65 ° C.

The technical problem solved by the developed invention is to obtain anti-icing reagent for transport equipment based on alkaline runoff of caprolactam production, characterized by low freezing temperatures (up to minus 75 ° C) and low content of modifying additives.

The technical result achieved by the implementation of the developed technical solution consists in increasing the efficiency of the antifreeze reagent by increasing the strength, flexibility and service life of the film formed on the metal surfaces, increasing the speed and degree of wetting of coal and other hydrophobic materials while maintaining the quality of the antifreeze reagent, such as low pour point and uniformity of composition.

To achieve the specified technical result, it is proposed to use the developed method for producing an anti-icing reagent for transport equipment, according to which the alkaline stock of caprolactam production is modified by treating it with siloxane, namely cyclic polydimethylsiloxane in an amount of 6.0 mass. %, or dimethylsiloxane in an amount of 9.0 mass. %, or hexamethyldisiloxane in an amount of 8.0 mass. %, or a copolymer of dimethylsiloxane with diphenylsiloxane when the ratio of monomers 70:30 in the amount of 6.0 wt. % The degree of completion of the modification reaction is fixed by measuring the pH of the solution.

Alkaline stockpile of caprolactam production (SHPSPK) is a by-product of caprolactam production obtained in the process of cyclohexane oxidation. ShchSPK is an aqueous solution of sodium salts of acidic by-products of air oxidation of cyclohexane, including, mass. %:

dry matter - 39.5-47.0

sodium salts of organic acids (in terms of sodium adipate) - 18.0-36.0

cyclohexanol - 0.7-0.8

cyclohexanone - 0.1-0.2

resin - 8.0-10.0

water - the rest

the pH of the solution is 10.0-14.0.

The pour point of ShchSPK is minus 35 ° C.

The introduction of modifying additives in SCHPPC reduces the freezing temperature to minus 75 ° C.

Modification of the alkaline runoff of caprolactam production is as follows. Using a pump, SCHSPK is pumped into the reactor from the storage tank, the required amount of modifying components (cyclic polydimethylsiloxane, dimethylsiloxane, hexamethyldisiloxane, a copolymer of dimethylsiloxane with diphenylsiloxane) is determined according to the norms of raw material consumption. After the introduction of the reagents into the SCSPC through the filler neck of the reactor, the composition is mixed by any known method to a homogeneous state. The degree of completion of the modification reaction is fixed by measuring the pH of the solution. Upon completion of the modification, the anti-icing reagent is poured into the container for the finished product.

The invention is illustrated by the following examples (a comparison of the obtained anti-icing reagent to substantiate the achievement of the specified technical result will be carried out with an anti-icing reagent according to patent RU 2550186).

Example 1

ShchSPK is pumped into the reactor using a pump from a storage tank in an amount of 94.0 mass. %, determine the required amount of modifying component - 6.0 mass. % cyclic polydimethylsiloxane. After the introduction of a modifying reagent into the SCSPC through the filler neck of the reactor, the composition is mixed until homogeneous. The degree of completion of the modification reaction is fixed by measuring the pH of the solution; the optimum value is pH 9.5-10.0. Upon completion of the modification, the anti-icing reagent is poured into the container for the finished product.

Example 2

ShchSPK is pumped into the reactor using a pump from the storage tank in the amount of 91.0 mass. %, determine the required amount of modifying component is 9.0 mass. % dimethylsiloxane. After the introduction of a modifying reagent into the SCSPC through the filler neck of the reactor, the composition is mixed until homogeneous. The degree of completion of the modification reaction is fixed by measuring the pH of the solution; the optimum value is pH 10.0-11.5. Upon completion of the modification, the anti-icing reagent is poured into the container for the finished product.

Example 3

ShchSPK is pumped into the reactor using a pump from the storage tank in the amount of 92.0 mass. %, determine the required amount of modifying component is 8.0 mass. % hexamethyldisiloxane. After the introduction of a modifying reagent into the SCSPC through the filler neck of the reactor, the composition is mixed until homogeneous. The degree of completion of the modification reaction is fixed by measuring the pH of the solution; the optimum value is pH 12.0-12.5. Upon completion of the modification, the anti-icing reagent is poured into the container for the finished product.

Example 4

ShchSPK is pumped into the reactor using a pump from a storage tank in an amount of 94.0 mass. %, determine the required amount of modifying component - 6.0 mass. % copolymer of dimethylsiloxane with diphenylsiloxane with a monomer ratio of 70:30. After the introduction of a modifying reagent into the SCSPC through the filler neck of the reactor, the composition is mixed until homogeneous. The degree of completion of the modification reaction is fixed by measuring the pH of the solution; the optimum value is pH 8.5-9.5. Upon completion of the modification, the anti-icing reagent is poured into the container for the finished product.

A comparison of the quality of the anti-icing reagent obtained in the above examples with the antifreeze reagent prepared according to the prototype (patent RU 2550186, publ. 05/10/2015) is presented in table 1.

Compared with the prototype (antifreeze reagent according to patent RU 2550186), the pour point of the developed anti-icing reagent is reduced by 17.2%; wear spot diameter reduced by 11.1%; welding load increased by 6.9%; contact angle reduced by 6.3 / 2.5%.

Thus, the use of a method for producing an anti-icing reagent for transport equipment, including alkaline runoff of caprolactam production and cyclic polydimethylsiloxane, or dimethylsiloxane, or hexamethyldisiloxane, or a copolymer of dimethylsiloxane with diphenylsiloxane, allows:

- reduce the pour point of the reagent;

- reduce the diameter of the spot wear of the reagent;

- reduce the contact angle of the reagent;

- increase the load of the welding reagent;

- reduce the consumption of modifying reagents.

Claims (13)

1. A reagent against freezing and sticking of overburden, coal, iron ore and other wet bulk materials to transport equipment, containing alkaline stockpile of caprolactam production (SHPSPK), which is a byproduct of caprolactam production and is an aqueous solution of sodium salts of acidic by-products of cyclohexane air oxidation and an additive, characterized in that as an additive contains cyclic polydimethylsiloxane in an amount of 6.0 wt.%, or dimethylsiloxane in an amount of 9.0 wt.%, or hex Sametildisiloxane in an amount of 8.0 wt.%, or a copolymer of dimethylsiloxane with diphenylsiloxane in an amount of 6.0 wt.%. 2. The reagent according to claim 1, characterized in that it contains as an additive cyclic polydimethylsiloxane in the following ratio of components, wt.%: ShchSPK 94.0 cyclic polydimethylsiloxane 6.0. 3. The reagent according to claim 1, characterized in that as an additive it contains dimethylsiloxane in the following ratio of components, wt.%: ShchSPK 91.0 dimethylsiloxane 9.0. 4. The reagent according to claim 1, characterized in that as an additive it contains hexamethyldisiloxane in the following ratio of components, wt.%: ShchSPK 92.0 hexamethyldisiloxane 8.0. 5. The reagent according to claim 1, characterized in that as an additive it contains a copolymer of dimethylsiloxane with diphenylsiloxane with a monomer ratio of 70:30 in the following ratio of components, wt.%: ShchSPK 94.0 copolymer of dimethylsiloxane with diphenylsiloxane 6.0.