The kinetics of non-catalyzed pinacol rearrangement in high temperature liquid water was investigated at 10 MPa and temperature from 180℃ to 220℃. Rate constants were evaluated with the first-order reaction assumpti...The kinetics of non-catalyzed pinacol rearrangement in high temperature liquid water was investigated at 10 MPa and temperature from 180℃ to 220℃. Rate constants were evaluated with the first-order reaction assumption. The activation energy evaluated was 176.4 kJ·mol -1 . The experimental results demonstrate that non-catalyzed pinacol rearrangement in high temperature liquid water is possible with high pinacol conversion and pinacolone yield over 80%.展开更多
An environmentally benign method to accelerate the pinacol rearrangement in high temperature liquid water by the addition of CO2 was proposed.The effects of CO2 initial pressure and temperature on the kinetics of pina...An environmentally benign method to accelerate the pinacol rearrangement in high temperature liquid water by the addition of CO2 was proposed.The effects of CO2 initial pressure and temperature on the kinetics of pinacol rearrangement were studied.The experimental results showed that the reaction rate could be greatly increased with the addition of CO2.The activation energies evaluated were 81.1 kJ·mol-1 without CO2,and 87.1 kJ·mol-1 with CO2 initial pressure at 0.2 MPa,which showed no significant difference.The main by-product was confirmed to be 2,3-dimethyl-3-butadiene by GC/MS and the possible reaction mechanism was proposed.展开更多
文摘The kinetics of non-catalyzed pinacol rearrangement in high temperature liquid water was investigated at 10 MPa and temperature from 180℃ to 220℃. Rate constants were evaluated with the first-order reaction assumption. The activation energy evaluated was 176.4 kJ·mol -1 . The experimental results demonstrate that non-catalyzed pinacol rearrangement in high temperature liquid water is possible with high pinacol conversion and pinacolone yield over 80%.
文摘An environmentally benign method to accelerate the pinacol rearrangement in high temperature liquid water by the addition of CO2 was proposed.The effects of CO2 initial pressure and temperature on the kinetics of pinacol rearrangement were studied.The experimental results showed that the reaction rate could be greatly increased with the addition of CO2.The activation energies evaluated were 81.1 kJ·mol-1 without CO2,and 87.1 kJ·mol-1 with CO2 initial pressure at 0.2 MPa,which showed no significant difference.The main by-product was confirmed to be 2,3-dimethyl-3-butadiene by GC/MS and the possible reaction mechanism was proposed.