Impact of coker wax oil on catalysis
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The impact of coking wax oil on catalysts: It is said that coking wax oil contains a high level of ammonia nitrogen, which has a significant effect on catalysts. However, after checking relevant information, I found that ammonia nitrogen does not have a very large impact on catalysts. I’m looking for the truth
It is mainly due to high levels of basic nitrogen; the acceptable value is no more than 1000. This condition damages the active centers of the catalyst, leading to its deactivation.
It can easily lead to temporary deactivation of the catalyst (by blocking the micropores of the molecular sieve), but its activity is restored after regeneration in a regenerator. In coking wax oil, not only the basic nitrogen affects the catalytic yield, but its group composition also plays a role in influencing the yield of light oils. Generally, coker wax oil is blended into catalytic feedstock; apart from judging based on basic nitrogen, it is difficult to assess it using parameters such as boiling range, residue, and sulfur content. Coker wax oil contains a high amount of polycyclic aromatics resulting from thermal cracking, and these compounds are difficult to open up during catalytic cracking reactions. In catalytic reactions, the yield of light oils from coker wax oil is only about 30%, of which 10% is gasoline and 20% is diesel; the remainder, as one can imagine, consists of slurry that cokes to produce dry gas.
Is this just a temporary deactivation? Then it shouldn’t have much impact on the catalyst. What is the approximate level of heavy metals in coker wax oil?
It’s best to avoid using this oil if possible; it makes the operation very difficult!
Another point to note is that if coker wax oil is used, the large amount of nitrogen oxides generated during combustion is a problem; how can environmental protection measures address this?
Yeah, the nitrogen oxide content in the smoke isn’t that high at the moment
I’m still quite concerned about its impact on the catalyst. As for the yield issue, I know that it hardly undergoes cracking, so less refined product is produced
Apart from preventing heavy metals from contaminating the catalyst, it should have little impact on the catalyst. These are personal opinions and may not be correct.
The amount of char formed is high, which reduces the reaction depth; as a result, the coking load on the regenerator increases, leading to a decrease in light oil yield
Coking wax oil is an intermediate product from secondary processing; it cannot be evaluated solely based on properties such as density and residue carbon content. Its cracking performance as a catalyst feedstock also needs to be considered, as it is closely related to the catalyst used. It is not suitable for use with any catalyst, so there must be limits on the proportion of this material mixed in – generally not more than 30% – or limits must be set on the alkaline nitrogen content in the catalyst feedstock.