C4 contains a large amount of methanol
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The C4 produced by MTBE contains a large amount of methanol of low purity; what is the reason for this? The methanol content detected in them is said to be around fifteen or sixteen; how can this situation be resolved? Awaiting everyone's answers~~~
The methanol content in the raw materials is high; strengthen the testing procedures!
Generally, a contract is signed with the raw material supplier, and the price is reduced based on the analysis results. It is advisable for the facility to have a washing system to remove methanol through washing
In MTBE plants, methanol is one of the raw materials; the ratio of isobutylene to methanol during feeding is generally maintained within the range of 1:1.0X. Since it is an acid-catalyzed reaction, the degree of reaction is almost complete, so no excess methanol remains. The alcohol-to-olefin ratio is now easy to detect and control, and there should not be large amounts of methanol in the C4 product after the reaction. Additionally, if the factory intends to deliberately mix methanol into gasoline, that is another matter.
Reply to 4# qugd: The key factor is the low price of methanol. Methanol producers in the C4 stream generally do not activate methanol recovery systems, which results in methanol being present in C4. However, a methanol content of around 2% in C4 is considered normal; if it’s higher, as mentioned on floor 4, it means that methanol has been artificially added
The presence of methanol in the unreacted C4 is generally due to an excessive alcohol-to-olefin ratio, or to the fact that the methanol recovery tower is not in operation. Reaching 15% seems a bit unreasonable; could there be an issue with the testing equipment that is causing inaccurate results?
Methanol has a boiling point of 64.5°C, while C4’s boiling point is –6°C. Methanol and C4 can form an azeotrope; they are capable of forming such mixtures. Could it be that the pressure in your extraction tower is low, causing methanol to end up in the C4 stream?