summarizes the glycerol conversion and the solketal yield from
the experiments conducted at 40C, 600 psi and WHSV of 4 h
1
with different acetone/glycerol molar ratio (acetone equivalent
ratio) of 2.0 and 6.0. Clearly, increasing of the acetone equivalent
ratio resulted in an increase of the solketal yield irrespective of
the catalysts used. These results are actually expected as an excess
in acetone could drive the reaction in its forward direction thermodynamically to increase the glycerol conversion. A higher concentration of reactant also promotes the reaction rate, leading to a
higher product yield. Similar observations in a batch reactor were
reported by Agirre et al.[3]In addition, the use of excess acetone
could also help enhance the catalytic life time by removing the
water formed on the catalyst surface (please be noted that adsorption of water on the catalyst surface would block the catalyst active sites and thus deactivate the catalyst)