Help with a distillation multiple-choice question.
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1. A certain binary ideal solution is separated using distillation; the composition of the product is xD and xW. When the feed composition is xF1, the corresponding minimum reflux ratio is Rm1; when the feed composition is xF2, the corresponding minimum reflux ratio is Rm2. If xF1 < xF2 and the thermal conditions of the feed are the same, then A. Rm1 < Rm2 B. Rm1 = Rm2 C. Rm1 > Rm2 D. It cannot be determined. Please explain this in detail
The distillation method is used to separate a certain binary ideal solution; the composition of the product is xD and xW. When the feed composition is xF1, the corresponding minimum reflux ratio is Rm1; when the feed composition is xF2, the corresponding minimum reflux ratio is Rm2. If xF1 < xF2 and the heat state of the feed is the same, then B. Rm1 = Rm2
There is a graphical method: R/(R+1) equals the slope of the line passing through Xf and perpendicular to the equilibrium line, and also equals (Xd, XD); since Xf1R2/(R2+1), C is obtained
The answer is definitely C. If the required product concentration xd is the same, the lower the feed concentration, the greater the reflux ratio needed, and the same holds true for the minimum reflux ratio