Absorption of ammonia by vacuum pumps
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Dear teachers, please help. I encountered the following problem during the experiment: When the system is under vacuum, a significant amount of ammonia enters the vertical reciprocating vacuum pump, which causes the oil inside the pump to emulsify, accelerates the wear of the piston rings, and prevents proper vacuum creation. Is there any way to ensure that ammonia is fully absorbed before it enters the pump? If liquid absorption is used, what should be done with the absorbing liquid? What about if solid absorption is used? How should it be handled? Thank you!
It is absorbed using pure water to produce ammonia for sale, or through low-temperature condensation.
I am currently working on experiments in the laboratory. The problem is that my experimental conditions require a negative pressure of less than 10 kPa. When the ammonia gas produced in the reactor (a 150 ml three-necked flask) passes through pure water for absorption, bubbling occurs quite intensely. I think it would be better to use solid acids; liquid absorption is not convenient! I originally used color-changing silica gel for absorption, but found that ammonia deactivates the silica gel; I plan to use solid phosphorus pentoxide instead. I also thought about low-temperature condensation, but due to limited laboratory facilities, I didn’t go with it