Washington to Seoul with stopover in Beijing

I have two different itineraries for this trip which means I purchased two different flight tickets: a UA flight from Washington to Beijing (July 8, 5 a.m.) and a KE flight from Beijing to Seoul (July 8, 7:10 p.m.)

On the way back to United States, I also have the same flights backward: a flight from Seoul to Beijing (Aug. 13, 8: a.m.) and a flight from Beijing to Washington (Aug. 13, 2 p.m.)

The reservations are on two different itineraries but confirmed.

Am I allowed to apply for the 72hrs free transit on both July 8 and Aug. 13? Thanks so much for your help.