We are working toward an energy efficient production method for cumene- an important feedstock chemical in the US. The current technologies used to produce isopropylbenzene (cumene) require use of large excess amounts of reactant benzene, an expensive and carcinogenic organic reactant. This makes necessary the use of energy-intensive distillation steps to separate the product from excess reactants, usually in a two step-process, (requiring cooling between the two steps). We have developed a reactive/distillation reactor, where reaction and separation occur in one step, with elimination of cooling and transport. This system allows for the separation of unreacted benzene from cumene, as it is produced. The main advantage is the high energy-savings, and may result in higher yield and selectivity than the traditional technologies.

Old technologies are energy intensive processes. They are multi-step processes that require heating (≈300 °C), cooling (for transport, ≈25°C) and reheating. The reheating uses highly-energy intensive distillation columns to separate the unreacted species and different produced species. Separation by distillation is based on their different relative volatilities or boiling points. More recent technologies (i.e. catalytic distillation, reactive distillation, etc.) are able to achieve reaction and separation of reactants and products by distillation in one single tower. However, these later technologies require use of high pressures to maintain benzene below its boiling point, given the fact that for distillation to take place requires a liquid phase.

Our new reactive/distillation technology also allows for reaction and partial separations in one column, but combines the advantages of separations based on variations in volatilities or boiling points with those based on the differences in molecular weight and densities without having to pressurize the system. In our system, vapor (unreacted) benzene separates from the (heavier) products to the differences in density and boiling points between the phases.