Inorganic salt fireproof anticorrosive paint and preparation method thereof

Abstract

According to the preparation method, chromium-aluminum phosphate is used as a binder, graphene oxide is used as a modified material, superfine chrome green, magnesium oxide, zinc oxide, zinc powder, alpha-alumina micro powder, mica powder, talcum powder and the like are used as fillers, and the inorganic salt fireproof anticorrosive coating is prepared under the cooperation of a plurality of functional assistants. And preparing the inorganic phosphate fireproof anti-corrosion coating. The coating is used for coating protection on metal and alloy surfaces in a high-temperature environment, and the corrosion resistance and oxidation resistance of the metal surfaces can be remarkably improved. When the coating is used for protecting metal and alloy-based engines, exhaust pipes, incinerators and the like, the service life of the metal and alloy-based engines, the exhaust pipes, the incinerators and

Description

Technical Field

[0001] This invention relates to the field of inorganic salt special functional coatings, and in particular to an inorganic salt fireproof and anticorrosive coating and its preparation method. Background Technology

[0002] The rapid development of industrial technology has placed increasing demands on power systems. These systems release significant amounts of heat and exhaust gases during operation. Engines, in particular, produce carbon dioxide, water vapor, acidic gases, hydrogen chloride, and a range of nitrogen and sulfur oxides, exposing the engine combustion chamber and exhaust system to high temperatures, high humidity, and corrosive chemical environments. Furthermore, the combustion of plastics such as polytetrafluoroethylene (PTFE), polyvinylidene chloride (PVC), and polyvinylidene chloride (PVDC) in incinerators generates halides and hydrogen halides. All these products are highly corrosive, leading to corrosion and oxidation on the incinerator surfaces in the combustion zone.

[0003] Anti-corrosion coatings for metal surfaces are divided into two types: organic protective coatings and inorganic protective coatings. Inorganic anti-corrosion coatings are mainly formulated with silicate or phosphate compounds as binders, along with various pigments, additives, and curing agents. Compared with organic coatings, inorganic coatings have certain advantages. Inorganic coatings can be used for extended periods within a temperature range of 400-1000℃, and can withstand short-term heating up to 1500℃. Secondly, inorganic coatings have excellent weather resistance and solvent resistance, and are environmentally friendly and non-toxic. Furthermore, the raw materials for inorganic coatings are abundant, resulting in low production costs. Phosphate coatings are one of the important varieties of inorganic coatings. However, existing phosphate coatings also suffer from poor water resistance, high brittleness, low strength, and low gloss. Therefore, the market urgently needs a modified inorganic phosphate fire-retardant and anti-corrosion coating with excellent physicochemical properties.

[0004] To address the problems existing in current phosphate coatings, this invention patent employs chromium aluminum phosphate as a binder, graphene oxide as a modifier, and ultrafine chromium green, magnesium oxide, zinc oxide, zinc powder, α-alumina micro powder, mica powder, talc powder, and other fillers, along with a variety of functional additives, to prepare an inorganic phosphate fireproof and corrosion-resistant coating. Summary of the Invention

[0005] The purpose of this invention is to provide an inorganic salt fire-retardant and anti-corrosion coating and its preparation method, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an inorganic salt fire-retardant and anti-corrosion coating and its preparation method, comprising the following components by mass percentage: 45-55% liquid aluminum dihydrogen phosphate, 1-3% chromium trioxide, 10-20% graphene oxide aqueous dispersion, 5-15% ultrafine chromium green, 2-5% magnesium oxide, 2-5% zinc oxide, 2-5% zinc powder, 5-10% α-alumina micro powder, 3-6% mica powder, 3-6% talc powder, 0.5-1% chromium nitrate, 0.5-1% dispersant, 0.2-0.5% defoamer, 0.5-1.5% anti-settling agent, and 0.5-1.5% thickener; Preferred: Includes the following steps: Step 1: Prepare chromium aluminum phosphate binder; Step 2: Prepare pigment paste; Step 3: Prepare graphene-modified phosphate fireproof and corrosion-resistant coating.

[0007] Preferably, in step one, liquid aluminum dihydrogen phosphate is added to a dispersion tank, chromium trioxide is added under medium-speed stirring, and the mixture is stirred for 30 minutes to obtain aluminum chromium phosphate binder.

[0008] Preferably, in step two, the chromium aluminum phosphate binder is added to a dispersion tank, and the dispersant, defoamer, pigments and fillers are added under medium-low speed stirring. The mixture is then dispersed at high speed for 30 minutes, and then ground in a sand mill to a fineness of less than 30 μm to obtain a pigment paste.

[0009] Preferably, in step three, the pigment paste is added to the paint mixing tank, and graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener are added under medium and low speed stirring. The mixture is stirred for 30 minutes and then filtered through a 200-mesh sieve.

[0010] The technical effects and advantages of this invention are as follows: This invention uses aluminum chromium phosphate as a binder, graphene oxide as a modifier, and ultrafine chromium green, magnesium oxide, zinc oxide, zinc powder, α-alumina micro powder, mica powder, talc powder, etc. as fillers, and in combination with a variety of functional additives to prepare an inorganic phosphate fireproof and corrosion-resistant coating. Detailed Implementation

[0011] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0012] This invention provides an inorganic salt fire-retardant and anti-corrosion coating and its preparation method. The composition of a graphene oxide-modified phosphate fire-retardant and anti-corrosion coating, by mass percentage, includes the following components: 45-55% liquid aluminum dihydrogen phosphate, 1-3% chromium trioxide, 10-20% graphene oxide aqueous dispersion, 5-15% ultrafine chromium green, 2-5% magnesium oxide, 2-5% zinc oxide, 2-5% zinc powder, 5-10% α-alumina micro powder, 3-6% mica powder, 3-6% talc powder, 0.5-1% chromium nitrate, 0.5-1% dispersant, 0.2-0.5% defoamer, 0.5-1.5% anti-settling agent, and 0.5-1.5% thickener. Preferably, the composition includes: liquid aluminum dihydrogen phosphate 48-55, chromium trioxide 2-3, graphene oxide aqueous dispersion 15-20, ultrafine chrome green 5-10, magnesium oxide 2-5, zinc oxide 2-5, zinc powder 2-5, α-alumina micro powder 5-10, mica powder 3-6, talc powder 3-6, chromium nitrate 0.5-1, dispersant 0.5-1, defoamer 0.2-0.5, anti-settling agent 0.5-1.5, and thickener 0.5-1.5. Application: Spray onto strictly treated metal surfaces. Dry film thickness: 20-30µm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0013] The properties of graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings are shown in the table below:

[0014] Performance indicators Test conditions result Coating color - green Solid content - 50.0% drying 500℃ / 2h - Adhesion (pull-off method) 500℃ / 2h 5.1MPa Adhesion (pull-off method) 850℃ / 5h 7.1MPa Low temperature resistance -45℃，10h The coating is intact High temperature resistance 900℃，5h The coating is intact Resistance to thermal cycling 900℃-10℃, 10 cycles The coating is intact Synthetic lubricant resistant 150℃，24h No change in coating Hydraulic oil resistant 150℃，24h No change in coating Diesel resistant room temperature, 72h No change in coating Water resistant Normal temperature, 168h No change in coating Resistant to synthetic seawater room temperature, 72h No change in coating Salt spray resistance 700h No change in coating Moist heat resistance 720h No change in coating Thermal shock resistance 10g, 10h The coating is intact Application areas: Primarily used for high-temperature corrosion protection of components related to aircraft engines, automobile engines, gas turbines, and incinerator combustion chambers.

[0015] Furthermore, the graphene oxide-modified phosphate fire-retardant and corrosion-resistant coating is composed of a single component: The composition of graphene oxide modified phosphate high-temperature resistant anti-corrosion coating: by mass percentage, it includes the following components: liquid aluminum dihydrogen phosphate 48-55%, chromium trioxide 2-3%, graphene oxide aqueous dispersion 15-20%, ultrafine chrome green 5-10%, magnesium oxide 2-5%, zinc oxide 2-5%, zinc powder 2-5%, α-alumina micro powder 5-10%, mica powder 3-6%, talc powder 3-6%, chromium nitrate 0.5-1%, dispersant 0.5-1%, defoamer 0.2-0.5%, anti-settling agent 0.5-1.5%, and thickener 0.5-1.5%. This invention also provides a method for preparing graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings, comprising the following steps: Step 1, Preparation of chromium aluminum phosphate binder: Add liquid aluminum dihydrogen phosphate to a dispersion tank, add chromium trioxide under medium-speed stirring, stir for 30 minutes to obtain chromium aluminum phosphate binder; Step 2: Add the chromium aluminum phosphate binder to the dispersion tank, add the dispersant, defoamer, pigments and fillers under medium and low speed stirring, disperse at high speed for 30 minutes, and then grind it to a fineness of less than 30 μm using a sand mill to obtain pigment paste; Step 3: Add the pigment paste to the paint mixing tank, add the graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener while stirring at medium and low speed, stir for 30 minutes, filter through a 200-mesh screen to obtain graphene oxide modified phosphate fireproof and anticorrosive coating.

[0016] Application: Spray onto strictly treated metal surfaces, with a coating thickness of 20-30 μm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0017] In the embodiments, the liquid aluminum dihydrogen phosphate is a colorless, odorless, viscous liquid that is readily soluble in water. It is used as an adhesive in refractory materials and inorganic coatings, with a temperature resistance of 1500℃. It exhibits good adhesion, high-temperature resistance, thermal shock resistance, peel resistance, resistance to high-temperature airflow erosion, and good infrared absorption and insulation properties. However, because its pH is 1-4, it is acidic and corrosive to metal substrates. Therefore, passivation of the liquid aluminum dihydrogen phosphate is necessary to minimize phosphate corrosion. Introducing a passivating agent into the liquid aluminum dihydrogen phosphate is an effective method.

[0018] Passivating agents include: chromium trioxide, magnesium chromate, molybdic acid, potassium molybdate, potassium dichromate, potassium permanganate, hydrogen peroxide, etc.

[0019] Liquid chromium aluminum phosphate is produced by adding an appropriate amount of chromium trioxide as a passivating agent to liquid aluminum dihydrogen phosphate and stirring the mixture. It has advantages such as good water resistance, low curing shrinkage, high high-temperature strength, and the ability to cure at low temperatures.

[0020] In the embodiments, the graphene oxide is a derivative of graphene, formed by the exfoliation of graphene oxide into single or multiple layers. It possesses a typical quasi-two-dimensional spatial structure, with numerous oxygen-containing groups on its sheets, exhibiting high specific surface energy, good hydrophilicity and mechanical properties, and excellent dispersion stability in water and most polar organic solvents. Compared to graphene, graphene oxide has superior performance, possessing not only excellent wetting properties and surface activity but also the ability to be exfoliated after intercalation by small molecules or polymers. Due to its unique structure, graphene materials possess many excellent physicochemical properties, including outstanding thermal and electrical conductivity, thermal and chemical stability, and high flexibility, making it a preferred reinforcing agent in composite materials, particularly advantageous in protecting metal surfaces from corrosion and oxidation.

[0021] In the embodiments, the ultrafine chromium green (particle size 500nm-2um), chromium trioxide, is a hexagonal or amorphous dark green powder with a metallic luster. It typically has two hues: light olive green and dark olive green, both with a metallic sheen. Its relative density is 5.21, melting point is 2266℃, and boiling point is 4000℃. It has excellent heat resistance, remaining unchanged at 1000℃, and also exhibits good resistance to acids and alkalis. It is insoluble in water, sparingly soluble in acids, but soluble in hot alkali metal bromate solutions. It is stable to light, atmosphere, and corrosive gases such as sulfur dioxide and hydrogen sulfide. It has high hiding power, but the color is not very bright, the particle size is relatively hard, resulting in slightly lower gloss in paints, and it is magnetic.

[0022] In the embodiments, the magnesium oxide is a white or pale yellow powder, odorless and tasteless, with a melting point of 2852°C and a boiling point of 3600°C. It has high fire resistance and insulation properties and can be transformed into crystals after being burned at a high temperature above 1000°C. Magnesium oxide is an alkaline oxide and has the general properties of alkaline oxides. It belongs to cementing materials, is a mild catalyst, and is a curing agent for phosphates.

[0023] In the embodiments, the zinc oxide is an oxide of zinc, a white solid, hence also known as zinc white. Besides its coloring and hiding power, zinc oxide is also a preservative and luminescent agent in coatings; furthermore, its excellent ultraviolet shielding ability gives it superior anti-aging properties in coatings. In inorganic phosphate coatings, it is used in combination with magnesium oxide as a curing agent.

[0024] In this embodiment, the zinc powder, a dark gray powder of metallic zinc, can be used as a pigment. It has strong hiding power and excellent rust prevention and atmospheric corrosion resistance. In the coating, the zinc powder provides sacrificial anode protection, thereby acting as a corrosion shield for the metal.

[0025] In this embodiment, the α-alumina micro powder, specifically the high-temperature calcined alumina powder, is made from industrial aluminum hydroxide or industrial alumina as raw materials. It is calcined at an appropriate temperature to form a crystal-stable α-alumina product. The alumina micro powder, produced by ball milling, is a white powder or fine sand with good flowability, stable properties, and is relatively difficult to dissolve in acidic or alkaline solutions. It also exhibits good sintering properties. The high-temperature calcined alumina powder product has a high melting point and excellent mechanical strength, hardness, and refractoriness.

[0026] In the embodiments, the mica powder is a commonly used flaky filler in coatings. Adding an appropriate amount of mica powder to the coating of the present invention enables the coating to shield against water, oxygen, and corrosive media, reduces the shrinkage rate of the coating, and improves the thermal shock resistance.

[0027] In the embodiments, the talc powder is a commonly used mineral filler in coatings. Adding an appropriate amount of talc powder to the coating of the present invention can reduce costs, reduce the shrinkage rate of the coating, and improve the thermal shock resistance.

[0028] In the embodiments, the chromium nitrate, a trivalent chromium salt, is used synergistically with the chromium trioxide as a corrosion inhibitor and passivator, which can further improve the application performance of the coating and enhance the physicochemical properties of the coating.

[0029] In the embodiments, the dispersant is selected from one or a combination of two of BYK-110 and sodium hexametaphosphate.

[0030] In the embodiments, the defoamer is selected from one or a combination of two of BYK-024, 681F, and NXZ.

[0031] In the embodiments, the anti-settling agent is selected as fumed silica.

[0032] In the embodiments, the thickener is selected as organobentonite. Specific Implementation

[0033] The following detailed description is provided with reference to specific embodiments: Example Example 1: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0034] The composition of graphene oxide modified phosphate fire-retardant and anti-corrosion coating, by mass percentage, includes the following components: Liquid aluminum dihydrogen phosphate 48%, chromium trioxide 3%, graphene oxide aqueous dispersion 20%, ultrafine chrome green 5%, magnesium oxide 2-5%, zinc oxide 5%, zinc powder 2%, α-alumina micro powder 5%, mica powder 6%, talc powder 3%, chromium nitrate 0.5%, dispersant 0.5%, defoamer 0.2%, anti-settling agent 0.5%, thickener 0.5%.

[0035] This invention also provides a method for preparing graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings. The preparation method of the graphene oxide modified phosphate fire-retardant and anti-corrosion coating provided by the present invention includes the following steps: Step 1, Preparation of chromium aluminum phosphate binder: Add liquid aluminum dihydrogen phosphate to a dispersion tank, add chromium trioxide under medium-speed stirring, stir for 30 minutes to obtain chromium aluminum phosphate binder; Step 2: Add the chromium aluminum phosphate binder to the dispersion tank, add the dispersant, defoamer, pigments and fillers under medium and low speed stirring, disperse at high speed for 30 minutes, and then grind it to a fineness of less than 30 μm using a sand mill to obtain pigment paste; Step 3: Add the pigment paste to the paint mixing tank, add the graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener while stirring at medium and low speed, stir for 30 minutes, filter through a 200-mesh screen to obtain graphene oxide modified phosphate fireproof and anticorrosive coating.

[0036] Application: Spray onto strictly treated metal surfaces, with a coating thickness of 20-30 μm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0037] Example Example 2: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0038] The composition of graphene oxide modified phosphate fire-retardant and anti-corrosion coating, by mass percentage, includes the following components: Liquid aluminum dihydrogen phosphate 50%, chromium trioxide 2%, graphene oxide aqueous dispersion 19%, ultrafine chrome green 6%, magnesium oxide 3%, zinc oxide 4%, zinc powder 5%, α-alumina micro powder 6%, mica powder 5%, talc powder 5%, chromium nitrate 0.6%, dispersant 0.6%, defoamer 0.3%, anti-settling agent 0.5%, thickener 0.5%.

[0039] This invention also provides a method for preparing graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings, comprising the following steps: Step 1, Preparation of Chromium Aluminum Phosphate Binder: Add liquid aluminum dihydrogen phosphate to a dispersion tank, add chromium trioxide under medium-speed stirring, and stir for 30 minutes to obtain chromium aluminum phosphate binder.

[0040] Step 2: Add the chromium aluminum phosphate binder to the dispersion tank, add the dispersant, defoamer, pigments and fillers under medium and low speed stirring, disperse at high speed for 30 minutes, and then grind it to a fineness of less than 30 μm using a sand mill to obtain pigment paste; Step 3: Add the pigment paste to the paint mixing tank, add the graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener while stirring at medium and low speed, stir for 30 minutes, filter through a 200-mesh screen to obtain graphene oxide modified phosphate fireproof and anticorrosive coating.

[0041] Application: Spray onto strictly treated metal surfaces, with a coating thickness of 20-30 μm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0042] Example Example 3: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0043] The composition of graphene oxide modified phosphate fire-retardant and anti-corrosion coating, by mass percentage, includes the following components: The formula consists of 50% liquid aluminum dihydrogen phosphate, 1.5% chromium trioxide, 15% graphene oxide aqueous dispersion, 5% ultrafine chrome green, 4% magnesium oxide, 3% zinc oxide, 3% zinc powder, 7% α-alumina micro powder, 4% mica powder, 4% talc powder, 0.7% chromium nitrate, 0.7% dispersant, 0.3% defoamer, 0.5% anti-settling agent, and 0.5% thickener.

[0044] This invention also provides a method for preparing graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings, comprising the following steps: Step 1, Preparation of Chromium Aluminum Phosphate Binder: Add liquid aluminum dihydrogen phosphate to a dispersion tank, add chromium trioxide under medium-speed stirring, and stir for 30 minutes to obtain chromium aluminum phosphate binder.

[0045] Step 2: Add the chromium aluminum phosphate binder to the dispersion tank, add the dispersant, defoamer, pigments and fillers under medium and low speed stirring, disperse at high speed for 30 minutes, and then grind it to a fineness of less than 30 μm using a sand mill to obtain pigment paste; Step 3: Add the pigment paste to the paint mixing tank, add the graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener while stirring at medium and low speed, stir for 30 minutes, filter through a 200-mesh screen to obtain graphene oxide modified phosphate fireproof and anticorrosive coating.

[0046] Application: Spray onto strictly treated metal surfaces, with a coating thickness of 20-30 μm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0047] Example Example 4: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0048] The composition of graphene oxide modified phosphate fire-retardant and anti-corrosion coating, by mass percentage, includes the following components: Liquid aluminum dihydrogen phosphate 53%, chromium trioxide 1%, graphene oxide aqueous dispersion 15%, ultrafine chrome green 5%, magnesium oxide 5%, zinc oxide 2%, zinc powder 3%, α-alumina micro powder 8%, mica powder 3%, talc powder 5%, chromium nitrate 0.7%, dispersant 0.8%, defoamer 0.3%, anti-settling agent 1%, thickener 0.5%.

[0049] Example 3: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0050] This invention also provides a method for preparing graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings, comprising the following steps: Step 1, Preparation of Chromium Aluminum Phosphate Binder: Add liquid aluminum dihydrogen phosphate to a dispersion tank, add chromium trioxide under medium-speed stirring, and stir for 30 minutes to obtain chromium aluminum phosphate binder.

[0051] Step 2: Add the chromium aluminum phosphate binder to the dispersion tank, add the dispersant, defoamer, pigments and fillers under medium and low speed stirring, disperse at high speed for 30 minutes, and then grind it to a fineness of less than 30 μm using a sand mill to obtain pigment paste; Step 3: Add the pigment paste to the paint mixing tank, add the graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener while stirring at medium and low speed, stir for 30 minutes, filter through a 200-mesh screen to obtain graphene oxide modified phosphate fireproof and anticorrosive coating.

[0052] Application: Spray onto strictly treated metal surfaces, with a coating thickness of 20-30 μm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0053] Example Example 5: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0054] The composition of graphene oxide modified phosphate fire-retardant and anti-corrosion coating, by mass percentage, includes the following components: Liquid aluminum dihydrogen phosphate 53%, chromium trioxide 1%, graphene oxide aqueous dispersion 15%, ultrafine chrome green 5%, magnesium oxide 5%, zinc oxide 2%, zinc powder 3%, α-alumina micro powder 8%, mica powder 3%, talc powder 5%, chromium nitrate 0.7%, dispersant 0.8%, defoamer 0.3%, anti-settling agent 1%, thickener 0.5%.

[0055] Example 5: Composition and preparation method of graphene oxide modified phosphate fireproof and anticorrosive coating.

[0056] This invention also provides a method for preparing graphene oxide-modified phosphate fire-retardant and anti-corrosion coatings, comprising the following steps: Step 1, Preparation of Chromium Aluminum Phosphate Binder: Add liquid aluminum dihydrogen phosphate to a dispersion tank, add chromium trioxide under medium-speed stirring, and stir for 30 minutes to obtain chromium aluminum phosphate binder.

[0057] Step 2: Add the chromium aluminum phosphate binder to the dispersion tank, add the dispersant, defoamer, pigments and fillers under medium and low speed stirring, disperse at high speed for 30 minutes, and then grind it to a fineness of less than 30 μm using a sand mill to obtain pigment paste; Step 3: Add the pigment paste to the paint mixing tank, add the graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener while stirring at medium and low speed, stir for 30 minutes, filter through a 200-mesh screen to obtain graphene oxide modified phosphate fireproof and anticorrosive coating.

[0058] Application: Spray onto strictly treated metal surfaces, with a coating thickness of 20-30 μm. Drying conditions: 120℃ / 2h, then 500℃ / 2h.

[0059] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An inorganic salt fire-retardant and anti-corrosion coating, characterized in that: By weight percentage, it includes the following components: 45-55% liquid aluminum dihydrogen phosphate, 1-3% chromium trioxide, 10-20% aqueous dispersion of graphene oxide, 5-15% ultrafine chromium green, 2-5% magnesium oxide, 2-5% zinc oxide, 2-5% zinc powder, 5-10% α-alumina micro powder, 3-6% mica powder, 3-6% talc powder, 0.5-1% chromium nitrate, 0.5-1% dispersant, 0.2-0.5% defoamer, 0.5-1.5% anti-settling agent, and 0.5-1.5% thickener.

2. The method for preparing an inorganic salt fire-retardant and anti-corrosion coating according to claim 1, characterized in that: Includes the following steps: Step 1: Prepare chromium aluminum phosphate binder; Step 2: Prepare pigment paste; Step 3: Prepare graphene-modified phosphate fireproof and corrosion-resistant coating.

3. The method for preparing an inorganic salt fire-retardant and anti-corrosion coating according to claim 2, characterized in that: In step one, liquid aluminum dihydrogen phosphate is added to a dispersion tank, and chromium trioxide is added under medium-speed stirring. After stirring for 30 minutes, chromium aluminum phosphate binder is obtained.

4. The method for preparing an inorganic salt fire-retardant and anti-corrosion coating according to claim 2, characterized in that: In step two, the chromium aluminum phosphate binder is added to the dispersion tank, and the dispersant, defoamer, pigments and fillers are added under medium and low speed stirring. The mixture is then dispersed at high speed for 30 minutes and then ground in a sand mill to a fineness of less than 30 μm to obtain a pigment paste.

5. The method for preparing an inorganic salt fire-retardant and anti-corrosion coating according to claim 1, characterized in that: In step three, the pigment paste is added to the paint mixing tank, and graphene oxide aqueous dispersion, defoamer, anti-settling agent and thickener are added under medium-low speed stirring. Stir for 30 minutes and filter through a 200-mesh screen.