Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia

OP-2-3products detected by HPLC (Figure 1). These results suggest that the Br∅nstedacidity brought by the solid catalyst is rather responsible of secondarytransformations of water soluble polymers and/or glucose derivatives as HMF. On theopposite, solid Lewis acids such as tungstated zirconia or tungstated aluminaexhibited a remarkable catalytic effect on the cellulose conversion which wasincreased from 30wt% to more than 55wt% and the proportion of water solublepolymers was strongly reduced. Yields of 27mol% in lactic acid and of 30mol% in2,5,hexanedione were achieved on AlW and ZrW respectively [2]. The beneficialeffect of solid Lewis sites was checked via partial exchange of the Br∅nsted sites ofCs 2 HPW 12 O 40 with Sn cations: the proportion of the polymeric products was reducedby half in presence of the Sn exchanged cesium salt.As a concluding remark, we have demonstrated the remarkable efficiency of solidLewis acids to produce valuable compounds from cellulose hydrolysis initiated bywater autoprotolysis.yield (mol %)70,0060,0050,0040,0030,0020,0010,000,00solubleoligosaccharides/polymersun identified products (HPLC)5-HMF2,5-hexanedionepropylene glycollevulinic acidformic acidlactic acidGlucosewithout solid catalystCs 2HPW12O40C-SO3HCs2SnxHyPW12O40AlWZrW[1]. V. Jollet, F. Chambon, F. Rataboul, A. Cabiac, C. Pinel, E. Guillon and N. Essayem, Green Chem11 (2009) 2052-2060.[2]. French Patent application Fr10/00.573.45