Acetone conversion increases almost linearly with temperature from 17 to 63 % between 200 and 300 °C (Figure ). At harsh reaction temperatures of 280 °C and above, there are notable fluctuations in the measured acetone conversions as represented by the increased error over five measurements at steady-state conditions. The selectivity to mesitylene shows a steady incline from 11 % at 200 °C to a maximum of 38 % at 260 °C but decreases for higher reaction temperatures as acetone is primarily converted to undetected products. The selectivity to the dimer mesityl oxide decreases with reaction temperature as the consecutive aromatization to mesitylene is favored.