Microwave Polarization-Enhanced Evaporation: Experiment and Theory

Our previous study revealed that during microwave evaporation of water, an electric field vertical to the liquid surface facilitates water evaporation. In this work, 12 kinds of organic solvents were adopted as experimental subjects. The experiment results verify that microwave polarization-enhanced evaporation represents a universal rule. Under identical conditions, the microwave electric field vertical to the liquid surface can increase the evaporation rate by up to 20% compared with the parallel electric field. This effect is associated with intermolecular forces, dipole moment, complex permittivity, and relative molar mass. GROMACS molecular dynamics simulations demonstrate that such a phenomenon originates from the reduction in surface tension and enthalpy of vaporization induced by the microwave electric field vertical to the liquid surface.