Microwave heating has unique advantages compared to convection-radiation heating methods including fast heating rate and selective heating of objects. This thesis studied two applications of microwave heating in the environmental field: adsorbent regeneration and oil sands coke activation. The thermal behavior during microwave heating of select adsorbents when dry or saturated with selected adsorbates was studied to assess the potential for using microwave heating to regenerate adsorbents. Strong microwave-absorbing adsorbents depicted faster heating rate when dry. Weakly microwave-absorbing adsorbents depicted faster heating rate when saturated with polar adsorbates. Fast activation of oil sands coke using microwave heating and KOH was successfully completed. The iodine number of the activated delayed coke obtained after 10 minutes of microwave activation was 1130 mg/g. The short activation time and simplicity of the process demonstrate that microwave-activation is a promising approach to convert oil sands coke into activated carbon adsorbent with high adsorption capacity.