Evaporation of hydrochloric acid solution
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For a hydrochloric acid solution with a mass concentration of 5%, the solution is continuously heated to facilitate evaporation; the vapor that is produced is then condensed. What is the relationship between the HCI concentration in the condensed liquid and the temperature of the original solution that was evaporated? Please discuss this.
I’m not sure what you mean ? ?
Should we start from a thermodynamic perspective to calculate the partial pressures of the components in binary azeotropes and create phase diagrams?
It seems that as the temperature rises, the concentration of the condensate should decrease; I’m not sure if this is correct, sorry
I’m not sure whether you’re using distillation or fractional distillation. In the case of distillation, the top temperature can reach 110 degrees, and the hydrochloric acid concentration can be 20% (at atmospheric pressure). For fractional distillation, you can conduct pilot tests to determine the parameters
Do you want to concentrate dilute hydrochloric acid? I don’t think it’s very cost-effective, considering the energy, labor time, and equipment. Other uses – discussed separately!
The higher the evaporation temperature, the greater the concentration of the liquid obtained upon condensation
This question may seem simple, but it actually has a lot to be explored. The boiling point of hydrochloric acid increases with concentration before decreasing again, with the peak value being the azeotrope temperature of 110 degrees Celsius. When it evaporates, water comes out first; there should be no HCL. Then the hydrochloric acid concentration increases, until reaching the azeotrope point, at which point hydrochloric acid comes out along with water. So, the concentration of condensate water may increase from low to high~~ and then stabilize. It’s unclear whether it will start at 0 and then go straight to the azeotropic concentration of 20.24%.
In such a highly concentrated solution, evaporation cannot occur without both water and HCl gas being evaporated; however, the specific ratio requires experimentation or simulation