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Oil removal using catalysts is considered by many to be impractically feasible. Is this technology reliable? As one of the important power sources in industrial production, the reliability of the quality of compressed air is of paramount importance for smooth operations. Generally, regarding the quality requirements for compressed air, the main focus is on the levels of contaminants such as water, oil, and dust present in it. Among them, the removal of pollutants such as oil contaminants and oil-water mixed contaminants has always been a challenge in improving the quality of compressed air. Ways to obtain oil-free compressed air: The method of using oil-free compressors at the source is employed to get oil-free compressed air. In manufacturing processes where strict requirements are placed on the oil content in compressed air, most companies opt for oil-free compressed air systems, among which screw-type oil-free compressors are the most widely used. Dry screw oil-free compressors compress air using a pair of intermeshing rotors, with the air in the compression chamber remaining in contact with no oil. Furthermore, water screw oil-free compressors use water in place of lubricant to achieve lubrication, cooling, sealing, and noise reduction for the compressor. These two types of products are widely used in actual production, but there are also some issues. For example, although the air in the compression chambers of these two types of compressors does not come into contact with lubricating oil, they are unable to remove the trace amounts of oily impurities present in the air itself. In the absence of subsequent advanced oil removal equipment, it is difficult for the oil content in the compressed air produced by these compressors to meet the Class_0 oil-free standard specified in ISO8573.1-2010. Furthermore, the special coating on the rotor of dry screw oil-free compressors wears out over time, causing the compression efficiency to decline as usage progresses ； Its maintenance costs are quite high. Oil-free screw compressors with water lubrication use water to lubricate the compression chamber; since the air itself is not pure, it is necessary to purify the circulating water. Otherwise, corrosion may occur in components such as the rotor, and the rotor requires high-quality materials, resulting in relatively high overall costs. “The method of “installing an oil removal device at the rear end” enables the production of oil-free compressed air using non-oil-free compressors. Specifically, conventional lubricated compressors are used to generate compressed air, which is then processed by downstream oil removal equipment to produce oil-free compressed air. Among the back-end treatment technologies, the two most representative ones are adsorption oil removal and catalytic oxidation oil removal. Adsorption oil removal primarily utilizes adsorbent materials such as activated carbon to absorb and remove oil contaminants; this method is simple and efficient. By choosing high-quality adsorption materials, it is easy to obtain oil-free compressed air. However, its problem is that the adsorption capacity of the adsorbent material is relatively limited; once it becomes saturated, it needs to be replaced, and this is not easy to determine. There is also a high risk of contamination by oily impurities in the back end, resulting in relatively high overall usage costs. Oil removal by catalytic oxidation works on the principle that oil pollutants (C6+ hydrocarbon mixtures) are converted into carbon dioxide and water under certain temperatures and in the presence of a catalyst. This paper will analyze the characteristics of catalytic oxidation for oil removal, providing insights for obtaining oil-free compressed air. Feasibility analysis of catalytic oxidation oil removal technology. 01 Technical reliability: The catalytic oxidation technology has been around since the 1960s, with nearly 50 years of development to date. Due to its mild operating conditions and low requirements for equipment, it is widely used in industrial production and environmental protection. Having been tested extensively in both laboratory and industrial settings, it boasts strong technical reliability. The oil contaminants in compressed air are organic compounds of the C6+ type from a chemical perspective, and catalytic oxidation technology can effectively convert and remove them. 02 can completely solve the problem of oil contamination in compressed air. Catalytic oxidation technology can effectively remove liquid oil, oil mist, and oil-gas gels, as well as the most difficult-to-remove oil vapors. It can remove the oil from compressor lubricant that mixes into the compressed air, as well as the oil present in the air entering the compressor. Therefore, compression air purification equipment based on catalytic oxidation technology can be used both after oil-lubricated compressors and after oil-free lubricated compressors, completely eliminating the problem of oil contaminants in compressed air. 03 Low equipment maintenance costs. One of the key components of catalytic oxidation technology is the catalyst, which enables oil-based pollutants to be converted into carbon dioxide and water at lower temperatures. The catalyst itself does not change, and there is no issue of consumption due to reactions; therefore, in theory it can be used indefinitely. Even taking into account the effects of operating conditions and environmental factors, it has a long service life, which results in low maintenance costs for users. 04 The entire system is highly versatile. The back-end compression air purification equipment based on catalytic oxidation can be used in conjunction with various types of compressors, such as screw oil-lubricated compressors, oil-free lubricated compressors, piston compressors, scroll compressors, and vane compressors. It covers a wide range of pressure levels, allowing for use in high-pressure, medium-pressure, and low-pressure applications, and thus it can fill the gap where no suitable oil-free lubricated compressor devices are available at certain pressure levels. 05 The low procurement cost of the entire system is different from that of the oil-free screw compressors and water-lubricated screw compressors mentioned earlier. The catalytic oxidation oil removal technology has been developed in China and comes with independent intellectual property rights; the quality of its products is on par with that of similar foreign products, and in some aspects it is even superior, all at a more reasonable price. For most compressed air users, installing a catalytic oxidation oil removal system directly after the existing compressor is sufficient to meet their need for oil-free compressed air.