BACKGROUND: Crude glycerol will increase to over 400 million L year(-1), 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 1,2-propanediol (I,2-PD). RESULTS: Cu-H4SiW12O40/Al2O3 catalysts with different H4SiW12O40 (STA) loadings were prepared for the hydrogenolysis of glycerol to produce I,2-PD in liquid phase. At 513 K, 6 MPa and LHSV of 0.9 h(-1) 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 I,2-PD. More important, both the initial glycerol conversion and I,2-PD selectivity were maintained over 250 h. CONCLUSION: I,2-PD can be continuously produced with high yields via the liquid phase hydrogenolysis of glycerol over Cu-H4SiW12O40/Al2O3. 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 bi-functional catalyst with the appropriate amount of both acid and metal sites. (C) 2010 Society of Chemical Industry