The effect of dimethyl ether on synthetic catalysts!
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Modern ammonia synthesis systems increasingly incorporate low-pressure hydroformylation units, and the highly active copper catalysts used in such units have the potential to accelerate the formation of dimethyl ether. What is one’s view on the impact of low-pressure hydroformylation units on ammonia synthesis, as well as their effect on the catalysts used in this process?
This is a well-posed question: when low-pressure methanol is integrated into the ammonia synthesis system, what are the components of the gas stream after the methanol? What is the impact of small amounts of by-product gas components on subsequent processes? Colleagues need to explore this in practice; those who have already achieved results are welcome to share! Of course, further questions are also welcome.
Reply to 3# yg20080707: Your question shouldn’t arise; it’s impossible for alcohol ethers to be present in urea, as the conditions do not permit it. Ammonia, during its synthesis or even after it is produced, cannot contain substances such as alcohol ethers. If such substances were to be present and enter the synthesis system, they would poison the synthesis catalyst and reduce its lifespan, but they will not end up in ammonia. Nor will it be incorporated into the urea production process.
I believe that in liquid ammonia, the presence of alcohol-ether compounds leads to the formation of new substances, such as methylamine, and so when liquid ammonia is used to produce urea, this substance naturally ends up in the urea production system We often notice an unusual odor on urea packaging. I’m not sure if anyone has studied this; it’s hard to say for sure. But whether this is true or not, we can all discuss and investigate it. I really want to find out the answer
The dimethyl ether synthesis reaction is a highly exothermic reaction, and the timely removal of the heat generated by this reaction is crucial for reactor design. If the heat cannot be removed from the catalyst bed in a timely manner, it will inevitably lead to a sharp rise in the temperature of the bed layer. This not only affects the progress of the reaction but also reduces the catalyst’s activity, eventually causing it to become inactive and shortening its service life
In the ligand alcohol process, the hydrogen-to-carbon ratio in the fresh gas fed into methanol synthesis is very high, resulting in relatively few side reactions; in other words, little dimethyl ether and other impurities are formed. This is probably why wax formation is minimal in this process!
The oxygen content in dimethyl ether causes the synthesis catalyst to oxidize repeatedly, gradually deactivating it until it loses its functionality, which in turn leads to an increase in pressure!
Sometimes we find that when a low-pressure aldol unit is integrated into the system, the synthesis reaction rate drops sharply and the system pressure fluctuates; once it is removed, the system returns to normal. How can this be explained?
Reply to 10# yfjin2010: Is there significant fluctuation during gas convergence, resulting in a slight increase?
There is no slight increase; rather, after integration, it can be observed that the temperature at the upper level drops and the hot spots move downward. It is necessary to maintain power supply for normal production or reduce the load in order to continue operating