The Entropy Effect in Furfural Loss Reactions

In In the chapters 6 and 7, it was discussed in detail that in furfural reactors any furfural in the vapor phase is safe , i.e. incapable of undergoing loss reactions, but that any furfural in solution can react with itself and with intermediates of the xylose-to-furfural conversion as the solution contains hydrogen ions capable of specific acid catalysis as well as neutral molecules capable of general acid catalysis . 

Inasmuch as the furfural loss reactions lead to larger molecules, they are analogous to polymerization, with its buildup of oligomer and polymer molecules from monomer molecules. In representing an increase in order , this buildup of larger molecules causes a decrease in entropy, so that the entropy change of the reaction ASr is a negative quantity. 

Reactions can proceed to any significant extent only when their change of free 

In polymerization technology, the temperature Tc is called the ceiling temperature of the reaction [115] as it represents the ceiling up to which the polymerization proceeds significantly, whereas above this temperature it becomes insignificant. 

The same reasoning applies to the loss reactions in furfural reactors Above a critical temperature Tc, there will be no significant loss reactions, and on the way to this 

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