Potential of ‘nanofluids’ to further intensify microreactors

Recent discovery of high enhancement of heat transfer in nanofluids may be applicable to the area of process intensification of chemical reactors through integration of the functionalities of reaction and heat transfer in compact multifunctional reactors. This may lead to the reduction in the processes footprint and energy intensity over the process life cycle, allow easier implementation of highly exothermic and endothermic reactions, and enable rapid quenching of reactions. A nanofluid based on benign TiO₂ material dispersed in ethylene glycol has been studied in an integrated reactor–heat exchanger. An up to 35% increase in the overall heat transfer coefficient was measured in the steady state continuous experiments. This resulted in a closer temperature control in the reaction of selective reduction of an aromatic aldehyde by molecular hydrogen and very rapid change in the temperature of reaction under dynamic reaction control.