Since the gas phase space is hermetically sealed under high pressure with nitrogen, can benzene-saturated vapor still evaporate?
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If the gas space of a benzene storage tank is sealed under high pressure with nitrogen, can benzene saturated vapor still evaporate? Based on the pressure-saturated vapor principle, is it correct to assume that as long as the nitrogen pressure is higher than the saturated vapor pressure of benzene, benzene cannot be released into the gas phase? Or regardless of what gas is used to hermetically seal the gas phase space, as long as it’s not this type of benzene gas, must the benzene gas vapor be released until the saturated vapor pressure is reached? ? Which understanding is correct?
Personally, I think the first explanation is correct!
Benzene will still evaporate into the atmosphere, and the atmospheric pressure may be higher than the saturated vapor pressure of benzene
Regarding the issue of saturated vapor pressure. http://bbs.hcbbs.com/thread-1371098-1-1.html This is a post I made earlier; actually, I’m still a bit confused. I wasn’t very familiar with forums at that time, so nothing followed.
Nitrogen sealing can effectively reduce the volatilization of the medium and minimize material loss, but due to the breathing effect of the storage tank, a small amount of loss still occurs
The liquid in the tank will definitely evaporate; it stops evaporating only when its partial pressure reaches the saturated vapor pressure. For example, the saturated vapor pressure of the medium is 10 kPa (absolute pressure), while the nitrogen sealing pressure is 0.6 Mpa. The pressure inside that tank is the pressure of the liquid vapor at 10 Kpa, plus the pressure of nitrogen. A small amount of fluid is inevitably carried out during breathing
Personally, I think both your first and second answers are relevant, but one should think in the way suggested by the second answer. This is because, according to Dalton’s law of partial pressures, \"in a gas mixture within any container, if no chemical reactions occur between the various components, then each gas is distributed evenly throughout the entire container, and the pressure it exerts is the same as the pressure it would exert if it occupied the entire container on its own.\" In other words, the pressure of a certain amount of gas in a container of fixed volume depends only on temperature. ”But please note that this is an ideal gas. Gases in actual production are certainly not ideal gases, but they can be approximated as ideal gases at low pressures ； So the question arises: what level of pressure, or how close to low pressure does it need to be to be considered low pressure? Personally, I think there is a significant difference between different substances when it comes to using pressure to change the distance between molecules to a large extent; for example, if it is compressed into a liquid at the critical state, then there is definitely a change. If the critical conditions are very high, then a very high pressure is required; such conditions cannot be achieved in industrial production but only in the laboratory, and in that case it can be considered an ideal gas. So it still needs to be analyzed. I checked, and the critical temperature for benzene is 288°C and 4898 kPa, which is not very high. If it is sealed with high-pressure nitrogen, this will have a significant effect on the partial pressure of benzene; clearly, Dalton’s law of partial pressures for ideal gases no longer applies in this case. So, regarding your question, the volatilization of benzene or its saturated vapor pressure is affected to a certain extent under high-pressure nitrogen sealing. Let’s analyze each specific issue individually.