Application of MSQ desulfurization catalyst in the desulfurization of semi-water gas
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The MSQ-13 desulfurization technology consists of adding an MSQ-13 type desulfurization catalyst and V2O5 to an alkaline solution. The MSQ-13 desulfurization catalyst is composed of hydroquinone, manganese sulfate, salicylic acid, and two organic chelating agents, L and L’. L has a good coordinating effect with Mn2+, preventing the formation of MnCO3 precipitates and thus maintaining a high concentration of dissolved manganese (Mn2+ compounds) in the desulfurization solution, which is beneficial for improving the regeneration capacity of this solution. L’ can coordinate with V2O5 together with salicylate ions; when used alongside V2O5, it helps to reduce the formation of VOS precipitates and lowers the amount of vanadium consumed, thereby enhancing V2O5’s ability to absorb H2S during the desulfurization process and improving the efficiency of desulfurization. When used together with FeSO4·7H2O, it forms Fe3L…L and Fe2L, effectively creating a new type of complexed-iron desulfurization method. However, this method is highly affected by HCN and is not suitable for desulfurizing semi-water gas. Those who have used MSQ are welcome to discuss related issues!
MSQ is best used in combination with dilute ammonia solution, as this facilitates the dissolution of salicylic acid
Is there any tower blockage when using the MSQ-13 desulfurization technology?
Our company has used both MSQ and PDS; however, we have concluded that MSQ is more effective at removing sulfur foam than PDS, while PDS performs better in terms of dissolving sulfur (it is more effective at clearing sulfur foam from the tower).
The DDS desulfurization technology uses an aqueous solution containing aerobic bacteria, phenolic substances, and alkaline substances with iron ions (hereinafter referred to as “DDS desulfurization solution”) to absorb organic and inorganic sulfur compounds from gases. During this absorption process, some insoluble iron salts are formed; with the help of the DDS chelating ligands, the aerobic bacteria can break down these insoluble iron salts, returning them to the solution in the form of active iron ions, thereby ensuring the stable presence of iron ions in various forms within the solution. Under the combined catalysis of phenolic substances and iron ions, the DDS desulfurization solution is oxidized using air, producing sulfur as a by-product, and the regenerated DDS desulfurization solution can be reused in a closed loop. When a solution composed of the DDS catalysts Na2CO3 and H2O comes into contact with the shift gas in the desulfurization tower, the following reactions occur: Na2CO3 + CO2 + H2O = 2NaHCO3; Na2CO3 + H2S = 2NaHS + NaHCO3; Fe2+ + H2S = FeS + 2H+; Fe3+ + H2S = Fe2S3 + 6H+; COS + H2O = H2S + CO2 (hydrolysis at room temperature under the action of the DDS catalyst); CS2 + H2O = H2S + COS (hydrolysis at room temperature under the action of the DDS catalyst). The S2 present in the liquid after H2S absorption is oxidized to S by air in the regeneration tank, and this sulfur appears as foam, thereby allowing the DDS catalyst solution to be regenerated for reuse. The reactions involved in this process are as follows: 2NaHCO3 = Na2CO3 + CO2 + H2O; Fe(OH)2 = Fe2+ + 2OH-; Fe(OH)3 = Fe3+ + 3OH-; HCO3- = H+ + CO32-; H2O = H+ + OH-; 2Fe3+ + S2- = 2Fe2+ + S. The DDS method can reduce the H2S content in shift gas to below 5 mg/m3, allowing the gas to be sent directly to an NHD unit for carbon removal. Currently, 1 kilogram of DDS catalyst, 5 kilograms of auxiliary materials, and 4 kilograms of active ferrous carbonate are added every two days. Depending on the total iron content, type B auxiliary materials may also be used. The cost per ton of synthetic ammonia produced is around 1 yuan. As the H2S content in the gas after desulfurization decreases, the conditions in the carbon removal system improve significantly, the carbon removal liquid becomes clearer, and the purification efficiency increases markedly under the same circulation volume. Decarbonization-related sulfur blockages are reduced, and the cleaning costs for decarbonization equipment and fillers are also significantly lowered.
Our factory uses MSQ; it provides good desulfurization results and there is no issue of tower blockage. We use soda ash solution in combination with MSQ, which results in lower consumption compared to other methods
Our factory has used many catalysts – MSQ, tannin, and 888 – but we still find that MSQ is the best option; it doesn’t easily cause blockages in the towers, and its price is reasonable. Vanadium pentoxide is also used occasionally, but it’s too expensive.
Each has its own advantages and disadvantages, and every type of product has a market. It may seem that the cobalt phthalocyanine series are more common, but upon closer inspection, substances such as tannin, iron-based compounds, MSQ, NHD, etc., also play a significant role.
MSQ is a desulfurization catalyst that was developed quite early on; it has a reasonable price and is also easy to use.
It’s not easy; salary: 13569738934