Abstract: This paper studied the potassium carbonate as the chemical activator for activated carbon preparation by microwave heating. With potassium carbonate as the activator and microwave as the heat source, the effects of impregnating time, chemical activator concentration, activation time and microwave power on the adsorption properties of activated carbons were studied by orthogonal test and the optimal results were obtained. The optimal results are microwave power 600 W, microwave time 6 min, chemical activator concentration 0.20 g/mL and impregnating time 24 h.Iodine adsorption value of activated carbon reached 1189.68 mg/g and ethylene blue discoloring ability of activated carbon reached 190 mL/g,and the yield was 29.48%. The specific surface area of activated carbon was 1186.10 m²/g, the total pore volume was 0.624 cm³/g and the micropore volume was 0.407 cm³/g. The adsorption properties exceeded the national standard of activated carbon.

Key words: microwave heating, pine sawdust, activated carbon, adsorption