Abstract
BACKGROUND: Crude glycerol will increase to over 400 million L year^β1^, and the market is likely to become saturated due to the limited demand for glycerol. The main aim of this work is to develop a novel process for the sustainable conversion of glycerol to 1,2βpropanediol (l,2βPD).
RESULTS: CuβH~4~SiW~12~O~40~/Al~2~O~3~ catalysts with different H~4~SiW~12~O~40~ (STA) loadings were prepared for the hydrogenolysis of glycerol to produce l,2βPD in liquid phase. At 513 K, 6 MPa and LHSV of 0.9 h^β1^ in 10% (w/w) glycerol aqueous solutions, the catalyst with 5% (w/w) STA showed the best performance with 90.1% of glycerol conversion and 89.7% selectivity to l,2βPD. More important, both the initial glycerol conversion and l,2βPD selectivity were maintained over 250 h.
CONCLUSION: l,2βPD can be continuously produced with high yields via the liquid phase hydrogenolysis of glycerol over CuβH~4~SiW~12~O~40~/Al~2~O~3~. Furthermore, the characterization indicated that catalyst acidity could be greatly modified by STA, which promoted Cu reducibility. It was also found that hydrogenolysis could be favored by a biβfunctional catalyst with the appropriate amount of both acid and metal sites. Copyright Β© 2010 Society of Chemical Industry