Separation of acetonitrile from water
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Which expert has conducted simulations on the separation of acetonitrile from water? I don’t know how to separate acetonitrile from water, which have an azeotrope, using distillation Please give me your guidance; thank you.
The two form an azeotrope, and pressure-swapped distillation using two columns can be employed
Could you give a detailed explanation upstairs?
4# flymx agrees with the person above; it’s similar to the separation of acetic acid from water, and extraction distillation can be used for this.
Please refer to the following: Vapour-liquid equilibrium data for the acetonitrile-water system were determined under conditions of 0.101 MPa and varying calcium chloride contents and amounts in the calcium chloride ethylene glycol solution. Experimental results show that a calcium chloride ethylene glycol solution, as an extractant, can eliminate the azeotrope of the acetonitrile-water system and increase the relative volatility of this system. The NRTL model was used to correlate the vapor-liquid equilibrium experimental data, and the maximum deviation between the calculated results and the experimental results was 0.030. Batch salt addition extraction distillation experiments were conducted on the acetonitrile-water system. An ethylene glycol solution with a calcium chloride mass fraction of 10% was used as the extractant to separate the acetonitrile-water system; the reflux ratio was 2:1, and the ratio of the extractant flow rate to the reflux flow rate was 1:1. The molar fraction of acetonitrile in the overhead distillate could reach 99%, with a recovery rate of 85%.
This post was last edited by Higee on 2009-9-9 11:56. This system can be implemented using pressure swing distillation PSD, but we have not seen any actual examples of it. Those who use extractive distillation, please let me know the extractant. Thank you
I have seen pressure swing distillation, but not salt-added extraction; acetonitrile and water mix very easily, so what is the efficiency of extraction in that case? Furthermore, once calcium chloride is added, all related equipment and pipelines must be made of expensive stainless steel; 316 may not be sufficient. Consider the cost.
It is extractive distillation, not liquid-liquid extraction; it has little to do with \"easy mixing\".
If extractive distillation is used, a mixed phase should be more advantageous.
This mainly depends on the contents of acetonitrile and water in the feed. If the acetonitrile level is high, differential pressure distillation is suitable; if the water content is high, extractive distillation should be used. We have industrial application examples for both approaches.