Some airports use propylene glycol as deicer for their runways, and Peak Ecoshield is propylene glycol 
The propylene glycol coolant costs much less than other liquid deicers (for example, Bare Ground's liquid deicers are $20+ a gallon and not sold in stores, while Ecoshield is $11 and easily available at Walmart)
Is there anything in the PG coolant that would prevent it from being good to melt ice on your driveway or sidewalk?

The propylene glycol coolant costs much less than other liquid deicers (for example, Bare Ground's liquid deicers are $20+ a gallon and not sold in stores, while Ecoshield is $11 and easily available at Walmart)
Is there anything in the PG coolant that would prevent it from being good to melt ice on your driveway or sidewalk?