Corrosion inhibitor for snow-melting agent with excellent corrosion resistance and application of corrosion inhibitor

Abstract

The invention discloses a corrosion inhibitor for a snow-melting agent, which is low in price, environment-friendly and excellent in corrosion resistance, and is mainly used for a chlorine salt snow-melting agent so as to reduce the loss caused by corrosion of the snow-melting agent to metal facilities such as roads and the like. The formula of the corrosion inhibitor mainly comprises D-sodium gluconate, an organosilicon polymer and urea. By simulating a chlorine salt environment causing metal corrosion, the corrosion inhibition effect of the composite corrosion inhibitor with different mass ratios in the formula is tested. On the basis, the formula composition is optimized, the formula composition with the best corrosion inhibition effect is determined, and the corrosion inhibition rate reaches 78.76%. The composite corrosion inhibitor formula has the advantages that through the synergistic effect of the three corrosion inhibition components, corrosion of the snow-melting agent to metal facilities such as roads can be effectively relieved, and the sustainable development purposes of environmental protection and resource saving are achieved.

Description

Technical Field

[0001] The invention belongs to the field of anti-corrosion of deicing agents, and specifically relates to a novel corrosion inhibitor formula for deicing agents with high efficiency and excellent corrosion resistance and application thereof. Background Art

[0002] Metal corrosion brings huge losses to the national economy. Every year, the world loses more than 700 billion US dollars in metal due to corrosion. The metal corrosion process is a complex multiphase reaction that occurs at the interface between metal and medium. Generally, corrosion starts from the surface and gradually invades the inside, weakening its function and shortening its service life. According to the different mechanisms of the corrosion process, it can be divided into two categories: electrochemical corrosion and chemical corrosion. Among them, electrochemical corrosion is the most common and common corrosion process. Electrochemical corrosion refers to the corrosion caused by electrochemical action when the metal surface comes into contact with the medium such as humid air, electrolyte solution, etc. due to the formation of micro-batteries. During the corrosion process, due to the action of two half-batteries, the anode produces Fe 2+ , the cathode releases OH - , generating Fe(OH)2, which then reacts with moisture and oxygen in humid air to finally generate rust. In order to minimize the damage caused by metal corrosion, researchers have developed a variety of anti-corrosion measures, among which adding corrosion inhibitors is one of the most widely used and effective anti-corrosion methods.

[0003] In northern my country, snowfall in winter causes snow accumulation and ice on the road, which affects people's travel safety. The commonly used snow removal method is mainly to spread snow-melting agents. Inorganic salt snow-melting agents represented by sodium chloride have the advantages of strong snow-melting ability, wide range of raw materials, convenient use and low cost, so they are widely used. However, the chloride ions in traditional chloride-type snow-melting agents are highly corrosive. When such snow-melting agents are used in large quantities, when the liquid after the snow-melting agent melts the ice and snow penetrates from the road surface into the reinforced concrete structure of the bridge body, flows into the sewer pipe, and contacts with metal road facilities, it splashes onto the metal accessories at the bottom of the motor vehicle during the driving process, which will cause corrosion to the metal to a certain extent, shorten its service life, and cause a lot of economic losses. Therefore, it is extremely necessary to find an economical and efficient anti-corrosion method that can be widely used while ensuring a low corrosion rate and controlling costs. In order to reduce the metal corrosion caused by the snow-melting agent, adding a small amount of corrosion inhibitor can greatly inhibit the corrosion of the metal, which plays an important role in resource protection and reducing material losses. The United States first began to use chloride salt rust-resistant de-icing agents, that is, adding a certain amount of corrosion inhibitor to the de-icing agent. At present, organic acid salt de-icing agents with potassium acetate as the main component are less corrosive, but expensive, so they can only be used for de-icing operations in key areas such as some airports and railways. Therefore, it is of great practical significance to develop a corrosion inhibitor for de-icing agents that is low in price, simple in composition, efficient in de-icing, and has excellent corrosion resistance.

[0004] The development of new, efficient and low-cost corrosion inhibitors for deicing agents is an important research topic in the field of metal corrosion protection. Based on this concept, the present invention adds several low-cost components with excellent corrosion inhibition performance to chloride salt deicing agents, and designs experiments to screen the components to invent a corrosion inhibitor for deicing agents with excellent performance. Under the premise of ensuring that the formulated corrosion inhibitor is environmentally friendly, a higher corrosion inhibition rate is achieved during the corrosion process of roads and other related metal facilities when the deicing agent is used. Summary of the invention

[0005] In view of the above research status, the purpose of the present invention is to propose a new type of environmentally friendly corrosion inhibitor with excellent corrosion resistance for sodium chloride-based deicing agent. The technical problem to be solved is the corrosion of chloride-based deicing agents on roads, bridges and surrounding metal facilities, and the formula of the corrosion inhibitor is given.

[0006] The corrosion inhibitor formula disclosed in the present invention is as follows:

[0007] A corrosion inhibitor for a sodium chloride type snow melting agent, characterized in that the component comprises sodium D-gluconate, urea and an organosilicon polymer.

[0008] The present invention conducts a dynamic simulation experiment through an RCC-III rotating coupon corrosion tester to test the corrosion inhibition effect of the corrosion inhibitor formula, and the highest corrosion inhibition rate reaches 78.76%. The corrosion inhibitor formula with the highest corrosion inhibition rate is: in the de-icing agent, the mass proportion of D-sodium gluconate is 2.69%, the mass proportion of urea is 0.56%, and the mass proportion of silicone polymer is 0.17%.

[0009] The present invention further discloses the influence of the change of the composition amount of the corrosion inhibitor formula on the corrosion inhibition effect, and the experimental method for verifying the corrosion inhibition rate is carried out according to the following steps:

[0010] (1) Preparation of water sample for chloride-based deicing agent: Dissolve 172.10 g of sodium chloride in 0.8 L of ultrapure water. The corresponding water sample has a total hardness of 0 mmol / L and an alkalinity of 0 mmol / L.

[0011] (2) Preparation of corrosion inhibitor formula: dissolve 2.36%-3.02% by weight of sodium D-gluconate, 0.39%-0.67% by weight of urea, and 0.11%-0.22% by weight of organosilicon polymer in the water sample prepared above;

[0012] (3) Dynamic coupon test for corrosion inhibition effect evaluation: Place a beaker containing water samples with different formulations of corrosion inhibitors in a rotating coupon corrosion tester, hang a carbon steel standard corrosion test piece (50×25×2mm) on it, and keep it in a constant temperature rotating coupon tester at 40 degrees for 48 hours. Weigh the weight of the coupon before and after corrosion, calculate the corrosion rate, and calculate the corrosion inhibition rate by comparing it with the corrosion rate of the coupon in the blank water sample.

[0013] (4) The calculation formula of corrosion inhibition effect is as follows:

[0014] Corrosion rate calculation formula:

[0015]

[0016] Where: ΔW is the weight change of the test piece before and after the test, g; s is the area of ​​the test piece, m 2 ; t is the immersion time, h is the corrosion inhibition rate A

[0017]

[0018] Wherein: m1′ and m1 are the masses of the coupons before and after the blank test, respectively, in g; m2′ and m2 are the masses of the coupons before and after the test with the addition of corrosion inhibitor, respectively, in g; Δm1 is the amount of rust in the blank test coupon, in g; Δm2 is the amount of rust in the coupon with the addition of corrosion inhibitor, in g.

[0019] The novel, highly efficient and environmentally friendly corrosion inhibitor formulation for deicing agent disclosed in the present invention has the following positive effects compared with the existing corrosion inhibitor formulations:

[0020] (1) Organic components are used to form a protective film on the metal surface through the synergistic effect of corrosion inhibitors, thereby inhibiting the occurrence of metal corrosion.

[0021] (2) The formula of the present invention is simple in composition and the raw materials used are low in cost, which is conducive to future large-scale application. DETAILED DESCRIPTION

[0022] The present invention is described below by specific embodiments. Unless otherwise specified, the technical means used in the present invention are methods known to those skilled in the art. In addition, the embodiments should be understood as illustrative rather than limiting the scope of the present invention, and the essence and scope of the present invention are limited only by the claims. For those skilled in the art, various changes or modifications to the components and dosages in these embodiments, without departing from the essence and scope of the present invention, also belong to the protection scope of the present invention. The sodium D-gluconate, organosilicon polymer, and urea used in the present invention are all commercially available and purchased from Aladdin Reagent Company, Tianjin Kewei Co., Ltd., etc.

[0023] Example 1

[0024] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.39%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH of 7.

[0025] Example 2

[0026] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.45%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH value of 7.

[0027] Example 3

[0028] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.56%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH of 7.

[0029] Example 4

[0030] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.67%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH value of 7.

[0031] Example 5

[0032] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.36%, the mass proportion of urea is 0.56%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH value of 7.

[0033] Example 6

[0034] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 3.02%, the mass proportion of urea is 0.56%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH value of 7.

[0035] Example 7

[0036] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.56%, the mass proportion of silicone polymer is 0.11%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH of 7.

[0037] Example 8

[0038] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.56%, the mass proportion of silicone polymer is 0.22%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH value of 7.

[0039] Appendix 1 summarizes the corrosion inhibition test results of Examples 1 to 8.

[0040] Appendix 1. Corrosion inhibition effect parameters of the embodiment of the deicing agent using the corrosion inhibitor formulation of the present invention

[0041]

[0042] Comparative test

[0043] Reference Example 1

[0044] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of urea is 0.56%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH of 7.

[0045] Reference Example 2

[0046] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: the mass proportion of sodium D-gluconate is 2.69%, the mass proportion of silicone polymer is 0.17%, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with pH = 7.

[0047] Reference Example 3

[0048] A new type of highly efficient and environmentally friendly corrosion-inhibiting snow-melting agent formula: urea accounts for 0.56% by mass, silicone polymer accounts for 0.17% by mass, and the balance is sodium chloride. The corrosion inhibition rate is tested in a water sample with a pH of 7.

[0049] Appendix 2 summarizes the corrosion inhibition test results of Reference Examples 1 to 3.

[0050] Appendix 2. Corrosion inhibition effect parameters of reference examples of deicing agents using the corrosion inhibitor formulation of the present invention

[0051]

[0052] By comparing with the reference example, it can be seen that the corrosion rate is significantly reduced after adding three composite corrosion inhibitors of sodium D-gluconate, urea and silicone polymer, which is higher than the corrosion inhibition effect of adding two corrosion inhibitor formulas. The corrosion inhibition rate of the three-component corrosion inhibitor reaches up to 78.76%, which can effectively inhibit the occurrence of metal corrosion.

[0053] Conclusion: From the corrosion inhibition results of the above examples, it can be seen that the corrosion inhibitor formula disclosed in the present invention has a good corrosion inhibition effect on sodium chloride type snow melting agent. The corrosion inhibition type snow melting agent formula is 2.69% by mass of sodium D-gluconate, 0.56% by mass of urea, 0.17% by mass of organic silicon polymer, and the balance is sodium chloride. The maximum corrosion inhibition rate in the water sample with pH = 7 reaches 78.76%. This is a new, efficient and environmentally friendly corrosion inhibitor formula for sodium chloride snow melting agent.

Claims

1. A new type of corrosion inhibitor for sodium chloride-based deicing agent, characterized in that The corrosion inhibitor component comprises sodium D-gluconate, organic silicon polymer and urea.

2. The corrosion-inhibiting de-icing agent formula of claim 1: the mass proportion of sodium D-gluconate is 2.36%-3.02%, the mass proportion of urea is 0.39%-0.67%, the mass proportion of organosilicon polymer is 0.11%-0.22%, and the balance is sodium chloride.

3. The use of the corrosion-inhibiting deicing agent described in claims 1 and 2 can effectively slow down the corrosion of steel and metal facilities caused by deicing agents mainly composed of sodium chloride.

4. The composite corrosion-inhibiting deicing agent described in claims 1 and 2 ensures the application of chloride salt deicing agents in efficient deicing.

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