Is a desulfurizer required for the treatment of raw materials in alkylation and C4 isomerization?
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Is a desulfurizer required for the treatment of raw materials in alkylation and C4 isomerization? The raw material comes from the C4 fraction after etherification of MTBE; the MTBE raw material is obtained from the gas processing unit, whose preceding stage is liquefied gas desulfurization. In this desulfurization process, sulfonated cobalt phthalocyanine is used for oxidation, while alkali washing is employed for desulfurization. Therefore, for C4 isomerization, alkylating feedstocks basically do not require desulfurizers – can it be understood that way?
The sulfur in the raw material was removed earlier
If purchasing materials, those coked liquefied gases should be bought after desulfurization, separation, and extraction before use
What method is used to desulfurize coking liquefied gas? Are zinc oxide or iron oxide desulfurizers being used?
It mainly depends on the quality of the raw materials supplied by your main supplier; generally, there is no need to use separate ones
The catalyst used for C4 isomerization is a molecular sieve; sulfur has little impact, so desulfurization is not necessary. Unless the isomerization unit is equipped with a selective hydrogenation unit, purification measures such as desulfurization are required to protect the hydrogenation catalyst.
MTBE catalysts also do not require desulfurization. As long as the sulfur content in the product is <10ppm, it is acceptable. If the sulfur content of the product is high, either pre-desulfurization or post-desulfurization processes can be employed.
The alkylation unit can be included or not, and it mainly depends on the design process. The sulfur in the raw materials can be removed by treatment with sulfuric acid in the reactor; therefore, it is possible to proceed without desulfurization, which reduces investment and energy consumption. The downside is however a higher consumption of acid. Most of the newly installed units use a desulfurization-free process. If there is a hydrogenation unit in the alkylation process, desulfurization is necessary to protect the hydrogenation catalyst. However, hydrogenation catalysts are very prone to poisoning; most manufacturers equipped with such units do not carry out hydrogenation but feed the material directly into the alkylation reactor.
Our carbon tetra-arylation unit does not have desulfurization treatment! Because the liquefied gas has already been desulfurized upon leaving the plant, and it is desulfurized again before entering the gas separation stage!
I was wondering if there are any materials available on C4 isomers or n-butane isomers. Our company is planning to install a set of auxiliary equipment soon, and we would like to learn more about them in advance. Thank you very much.