propylene glycol is normally made from propylene oxide gas found in petro stream.
production from glycerol to propylene glycol may be possible but economics would have to looked into.
whether its for research/academic or bussiness?
rgds
shivanand shenoy
I found this paper on hydrolysis of glycerine. The products are chiefly propylene glycol, ethylene glycol and 1,3-propanediol which will need to be separated.