I wish to design the dehydration of ethanol at the least possible costs. Can this be done at temperatures around 80 to 100 degrees and lower pressures?
Acid catalyzed dehydration requires protonation of the hydroxyl group, so to boost activity you must boost the acid's ability to protonate. Usually this is done with high temperatures, but it can also be done with stronger acids. Since you are dehydrating a mono-ol you are going to need a very strong acid at those temperatures. You might need a superacid; I'm not sure if the traditional zeolite catalysts will work; heteropolyacids *might,* but they might not be strong enough at such low temperatures.
At 80-100 degrees ethanol is volatile, and one advantage of gas phase is that you will get a lot less ether formation in the gas phase. Here's one paper worth checking out:
Macht2009: J. Macht, R. T. Carr and E. Iglesia, Functional assessment of the strength of solid acid catalysts, 2009
Sulfuric acid or phosphoric acid but H3PO4 is favored although it is more costly. Never use HCl for the purpose of dehydration of an alcohol.
In doing the reaction in universities or in chemical plants, the temperature is usually (in the range you mentioned) & the pressure is just the prevailing atmosheric pressure.
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