The exhaust gas contains HCl and HBr; should the water amount required for absorption be calculated separately for each? !
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Assuming that 1000 g of water can absorb 100 g of HCl and 200 g of HBr, then is the amount of water required to absorb 100 g of HCl and 200 g of HBr 2000 g? ! Or is 1000g enough? It should be calculated according to Henry’s law, right? Will the absorption of HCl affect the absorption of HBr by water? Please give me some advice!
At constant temperature and pressure, the solubility of a gas in a solution is proportional to its equilibrium pressure above the liquid surface. This is Henry’s law, one of the fundamental laws in physical chemistry. If the equilibrium partial pressures of the two gases under standard conditions cannot be found, please lend a hand downstairs
The two will always act synergistically or antagonistically, right?
It has an impact, but since the volume of water is quite large, the effect can be practically ignored. It’s still content on physical chemistry
Do you mean 1000g is enough?
The volume ratio of hydrogen chloride to water for dissolution is 1:500. 100g of hydrogen chloride is less than 3 moles, so it’s around 62 liters. Only 130g of water is sufficient (saturated). Then, the isoelectronic effect of hydrogen bromide and hydrogen chloride causes hydrogen chloride to precipitate out. If it doesn’t precipitate at all and a large amount of water is required, it depends on the extent. If the amount of substance separated is not taken into account, it’s no problem for 130G of water to absorb these two substances ； If it does not precipitate at all, an infinite amount of water is required.
Okay, thank you. Relatively accurate calculations must also be quite complex, right? Can ASPEN do it?
This post was last edited by arpcd on 2018-2-2 at 11:49. Go and check the basic data; both HCl and HBr are gases with extremely high solubility. How could you think they would obey Henry’s law? ? Both of these substances deviate significantly from Henry’s law. . . In actual engineering applications, the issue of heat of dissolution also needs to be taken into account. To dissolve 1 kg of HCl, it is necessary to vaporize approximately 0.7 kg of H2O. Due to the very high heat of dissolution of HCl, it is essential to vaporize water in order to maintain the system’s temperature. I can’t recall the value for HBr; you’ll need to look it up yourself. It’s likely to be a significant value as well. What does this mean? To dissolve 1 kg of HCl, in addition to the water needed to dissolve it (for example, 0.5 kg), which is part of the material balance, an additional 0.7 kg of water must be added for vaporization, which is part of the heat balance. . . In total, you need to add at least 0.5 + 0.7 = 1.2 kg of water. . . Find someone familiar with the topic to do some simulation calculations for you. . . Aspen and ProII are both acceptable; it’s necessary to choose an electrolyte module. . .
Okay, thank you! :victory: