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Gas purification is an important process step in chemical industry production. In particular, the widespread use of technologies such as rough desulfurization of gas in fertilizer plants, secondary desulfurization of feed gas, desulfurization of shift gases used in the production of methanol and caustic soda, and advanced desulfurization methods for carbonization feed gas has **optimized the production processes. Currently, in the application of desulfurization technologies in the fertilizer and chemical industries, various new process flows are developed by organically combining refined desulfurizing agents, hydrolysis catalysts, and organic sulfur purifiers, depending on the amounts of H2S, COS, and CS2 remaining in the feed gas. In light of the continuous innovation in desulfurization technologies and the problems encountered in actual production, experts suggest that research on desulfurization technologies in China should focus on the following six key issues: the problem of mass transfer resistance in wet desulfurization. The view that wet desulfurization is controlled by mass transfer has been confirmed. Although the emergence of the PDS (cobalt phthalocyanine) desulfurization method has demonstrated the great effectiveness of new liquid-phase catalysts—allowing for good desulfurization results with just a small amount of PDS—it does not negate the fact that previous approaches to improving mass transfer in wet desulfurization were incorrect. In fact, technologies such as structured packing and vertical sieve plate towers, developed in recent years, have enhanced the mass transfer process, leading to new developments in desulfurization applications. Sulfur recovery in wet flue gas desulfurization: The desulfurization equipment used in fertilizer plants in China not only serves to purify gases but also converts hydrogen sulfide into elemental sulfur. However, the recovery rate of this sulfur resource is low; much of it is lost through emissions, and sulfur buildup often occurs within the towers, severely affecting production. Too fine sulfur particles are difficult to filter and recover, and they also have a strong adhesion to the filler and vessel walls. Therefore, trying to make the sulfur particles as thick as possible and minimizing the suspended sulfur in the desulfurization solution will help solve this problem. Patterns of sulfur compound changes in the ammonia synthesis production chain: Hydrogen sulfide and organic sulfur in ammonia plant gases are subject to constant changes. At present, we know relatively much about the variations in hydrogen sulfide, but little is known about the patterns of change in carbonyl sulfide and carbon disulfide. By analyzing the changes in sulfur across various processes in nitrogen fertilizer plants, such as conversion, carbonization, copper washing, and ammonia separation, it was found that organic sulfur is significantly reduced not only through hydrolytic transformation during the conversion process, but also to varying degrees as it comes into contact with ammoniacal solutions or liquid ammonia; this effect is particularly pronounced for carbonyl sulfide. During the carbonization stage, carbon dioxide exerts a \"substitution\" effect, resulting in a sharp increase in the organic sulfur concentration at the outlet of the main tower. Due to the low temperature and good gas-liquid contact, ammonia has an excellent ability to remove carbonyl sulfide. Sulfur poisoning of ammonia catalysts is likely caused more by carbon disulfide. Furthermore, in the transformed hot-water saturated system, a small amount of hydrogen sulfide will undergo further deep oxidation to form sulfates, which affects the production of food-grade ammonium carbonate. Therefore, revealing the variation patterns of sulfides in this production chain should be one of the research directions. The proper selection of desulfurization and decarburization processes is crucial for large nitrogen fertilizer plants; methods such as methanol washing, NHD, MDEA, and HS can be used to simultaneously remove sulfur and carbon, reducing the concentrations of H2S, CO2, and organic sulfur to very low levels. In facilities that use coal-derived gas for the production of small and medium-sized nitrogen fertilizers, the situation becomes more complex due to the presence of oxygen in the gas. Due to the low sulfur capacity of dry desulfurization agents, it is necessary to use them before decarburization; in fact, high concentrations of CO2 prior to decarburization affect desulfurization, especially precise desulfurization. Experts point out that in the desulfurization of transformed gas, dry and wet methods should be used in a rational combination to minimize costs and achieve the best results. Technology must be continuously improved. Fine desulfurization has drawbacks such as a long process, low sulfur capacity, and limited functionality; it would be more efficient to remove trace amounts of hydrogen sulfide and organic sulfur within a single tower. At the same time, further research is needed into the ability of fine desulfurization agents to remove organic sulfur. Furthermore, the development of technologies for removing thiols, thioethers, thiophenes, etc., should be carried out as soon as possible. Experts predict that if the goal of achieving complete removal of organic sulfides is attained, low- and medium-temperature desulfurization processes are likely to fully replace the medium-temperature desulfurization processes based on hydrogenation desulfurization. Organic sulfur release during advanced desulfurization: In advanced desulfurization, after the gas passes through the desulfurization equipment, a phenomenon known as \"sulfur release\" occurs, where the concentration of carbonyl sulfide at the outlet is higher than that at the inlet, which affects normal operation. The reasons for this phenomenon are as follows: competitive adsorption of CO2 and COS ； The absorption of H2S is relatively delayed, leading to surface accumulation that reacts with CO2 to form COS ； If the desulfurizer is too dry or contains too little oxygen, H2S accumulates on its surface and cannot be converted into elemental sulfur in a timely manner, resulting in the formation of COS. Therefore, in-depth study of the sulfur release mechanism is of great significance for optimizing process conditions and improving desulfurization efficiency.