Ethanol CHAP process

Further work on these various processes may be needed to optimize catalyst life, separation, and recycle, as well as reaction rates. The preferred solvent, if any is required, would be ethanol instead of methanol, for the former is less toxic and can be produced readily from renewable sources by fermentatation (see Chap. 9). 

Mass is additive. Can balances be done based on the volume rate of the streams in a given process No, because volume is not always additive. When you add X kg of material A to K kg of material B, you will always obtain X + F kg of the A and B mixture. We cannot say the same of volume. For example, 1 L H2O plus 1 L ethanol (at ambient conditions) will give you less than 2 L of the mixture. On the other hand, 1 kg H2O plus 1 kg ethanol will always give you 2 kg of the mixture. Students are encouraged to investigate why sometimes (as in the example of H2O plus ethanol) the volume is not necessarily additive and why the resulting volume, as in this example, is different than expected (see solved problem 12 in Sect. 5.3.2, Chap. 5). 

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