Microwave chemistry: Effect of ions on dielectric heating in microwave ovens

Abstract

To understand the interactions of microwaves with dielectric materials and their conversion to thermal energy in aqueous systems, the effect of ionic concentration has been studied. Aqueous solutions of inorganic ions were exposed to microwaves (2.45 GHz) in a modified oven under identical conditions. Difference in solution temperatures with reference to pure (deionized) water was monitored in each case. A significant decrease in the temperature was observed with an increase in the quantity of ions. Experiments were repeated with several inorganic ions varying in size and charge. The information can be helpful in understanding the role of ions during dielectric heating.

Keywords

• Concentration of ions
• Dielectric heating
• Dipolar polarization
• Ionic conduction
• Microwaves