Removal of H2S and CO2 from COS gas.
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Recent research has focused on the synthesis of COS, but due to the hydrolytic properties of COS itself, the levels of CO2 and H2S in the product are always very high (>3000 ppm). I’ve found that low-temperature methanol can be used to remove H2S. I would like to know what will happen if COS gas containing CO2 and H2S is passed through low-temperature methanol Will H2S and CO2 be removed?
Dust can be removed, provided that low-temperature methanol is used; low-temperature methanol has a strong absorption capacity for hydrogen sulfide and carbon dioxide.
Low-temperature methanation can also remove a small amount of COS; what do you use to synthesize COS?
A slight increase in COS loss is acceptable; can H2S and CO2 be reduced to levels below 100 ppm? I synthesized it using sulfuric acid + ammonium bisulfate
Our plant uses low-temperature methanol to remove hydrogen sulfide and carbon dioxide; the level of carbon dioxide is 20 ppm, while that of hydrogen sulfide is 0.1 ppm
It’s indeed very low! Could low-temperature methanol vapor be carried into the purified gas? How much can be brought in?
Theoretically, low-temperature methanol washing can meet this requirement, but low-temperature methanol also has a certain absorption capacity for COS, and the process is relatively complex; as a result, the investment required for such a COS production facility is quite high. Methanol washing is suitable for large-scale purification units. Therefore, it is not recommended to use this technology.
Recently, I have also seen desulfurization using the NHD method. Which method is more suitable for my purification requirements compared to the low-temperature methanol method? Additionally, I see that the operating pressure for both of these processes is around 3 Mpa, while I can only achieve a pressure of 0.1 Mpa here. Can this meet the requirements for gas purification?
Using low-temperature methanol washing certainly poses no problem; the economic viability needs to be examined.
The wet method for producing COS involves numerous side reactions, makes purification difficult, and generates a large amount of wastewater that needs to be treated
This post was last edited by renchy2000 on 2018-8-24 08:18. Theoretically, NHD can meet your requirements, but its absorption efficiency is greatly affected by system pressure; at lower pressures its solubility is low as well. A large amount of circulation is required, and similar to low-temperature methanol washing, it also needs an ice machine, with installation costs second only to those of low-temperature methanol washing. I do not recommend this technology. I suggest you consider MDEA; this technology is suitable for applications with low flow rates, and it requires a lower investment.