Analysis of Test Data for Corrosion Resistance of Hastelloy Alloy in MIBK Reactor

in the chemical industry, the reactor as an important production equipment, the choice of materials is very important. Because MIBK (methyl isobutyl ketone) is a polar organic solvent with high chemical activity and corrosion resistance, it is particularly important to choose corrosion-resistant materials in the MIBK reactor. As a kind of high performance corrosion resistant alloy, Hastelloy has been widely used in chemical industry because of its excellent corrosion resistance and high strength. In this paper, the corrosion resistance test data of Hastelloy alloy in MIBK reactor are analyzed in detail.

What is Hastelloy?

Hastelloy (Hastelloy) is a nickel-based high-temperature alloy with excellent corrosion resistance. It can not only work under high temperature and high pressure, but also resist the erosion of many strong corrosive media. The chemical composition of Hastelloy contains a variety of alloying elements, such as chromium, molybdenum, tungsten, etc., which make it perform well in complex environments. Therefore, Hastelloy is widely used in chemical, petroleum, pharmaceutical and other fields.

MIBK reactor working environment on the material requirements

MIBK is a common organic solvent with high solubility and polarity. In the MIBK reactor, the material needs to withstand chemical corrosion, mechanical stress and temperature changes and other factors. Common types of corrosion include chemical corrosion, electrochemical corrosion, and stress corrosion cracking. Therefore, when selecting corrosion-resistant materials, we must consider their performance in different environments.

Corrosion Resistance Test of Hastelloy in MIBK Reaction

in this test, we used electrochemical test method and corrosion test method to analyze the corrosion resistance of Hastelloy alloy in MIBK solution. The following are the main contents of the test and data analysis:

1. Electrochemical testing

electrochemical test is one of the important means to evaluate the corrosion resistance of materials. The corrosion mechanism of Hastelloy alloy in MIBK solution can be understood by polarization curve test and electrochemical impedance spectroscopy (EIS) analysis.

• polarization curve test: The results show that the corrosion current density of Hastelloy alloy in MIBK solution is low, indicating that it has good corrosion resistance.
• Electrochemical Impedance Spectroscopy (EIS): EIS analysis shows that the Hastelloy alloy in MIBK solution formed a stable passivation film, which can effectively prevent the further corrosion reaction.

2. Corrosion rate test

corrosion rate is an important index to measure the corrosion resistance of materials. Through the weight corrosion rate calculation formula, we obtain that the corrosion rate of Hastelloy alloy in MIBK solution is 0.1~0.3mm/a (year), which is much lower than the corrosion rate of stainless steel and other common alloys.

3. Stress corrosion cracking testing

MIBK solution is easy to cause stress corrosion cracking, so we carried out a special stress corrosion cracking test. The results show that no obvious stress corrosion cracking occurs in MIBK solution, which proves that the Hastelloy alloy has excellent corrosion resistance in this medium.

Effect of test conditions on results

during the test, we found that the test conditions (such as temperature, solution concentration, solution pH, etc.) have a significant effect on the corrosion resistance of Hastelloy. Specific performance is:

• temperature effect: With the increase of temperature, the corrosion rate of Hastelloy alloy increases slightly, but it is still within the acceptable range.
• Effect of solution concentration: The concentration of MIBK solution has a great influence on the corrosion rate. When the concentration is lower than 30%, the corrosion rate is low, and when the concentration is higher than 50%, the corrosion rate increases significantly.
• Effect of solution pH: The pH value of MIBK solution is neutral, which has little effect on the corrosion resistance of Hastelloy alloy.

Conclusions and recommendations

through this test, we draw the following conclusions:

1. the corrosion resistance of Hastelloy alloy in MIBK reactor is excellent, especially in the medium and low concentration solution.
2. The test results show that Hastelloy alloy can form a stable passive film in MIBK solution, which can effectively resist corrosion.
3. In practical application, it is suggested that the thickness and surface treatment process of Hastelloy alloy should be reasonably selected according to the concentration of MIBK solution and operating conditions.

As an ideal material for MIBK reactors, Hastelloy can meet the high requirements of the chemical industry for corrosion resistance. It is hoped that the analysis of this paper can provide reference for related industries and provide data support for future material optimization research.