Recent advances in biomass hydrolysis with solid acid catalysts have shown that solid acid catalysts, which have favorable characteristics such as efficient activity, high selectivity, long catalyst life and ease in recovery and reuse, have great potential for efficiently transforming lignocellulosic biomass into biofuels, and can replace many conventional liquid acids for hydrolysis and pretreatment. The development of novel highly acidic solid catalysts with special characteristics (e.g., magnetic properties) and nanometer size is a key issue for the effective hydrolysis of biomass

Prof. FANG Zhen of Xishuangbanna Tropical Botanical Garden (XTBG) was invitedby Prof. N.A. Chigier, Editor of Progress in Energy and Combustion Science (PECS) to contribute a review paper in this area.

Dr. GUO Feng and Prof. FANG Zhen from Xishuangbanna Tropical Botanical Garden (XTBG) summarized and analyzed current achievements in the hydrolysis of cellulose using solid acid catalysts in an article published in Progress in Energy and Combustion Science. They reviewed biomass hydrolysis with H-form zeolites, transition-metal oxides, cation-exchange resins, supported solid acids, and heteropoly compound in detail. It was concluded that the highest yields that have been achieved with solid acid catalysts are with those that have had a modest surface area and acid amount along with a high catalytic site concentration. Methods to promote reaction efficiency or increase selectivities such as microwave, ultrasonication and nanotechnology are also introduced. However, separation of solid catalysts from solid biomass residues after hydrolysis for reuse tends to be difficult.

They suggested that incorporating paramagnetic nanoparticles into the carbonaceous carriers is a practicable method to improve the separation and reuse of solid catalysts. Moreover, nanoparticle solid catalysts could provide new methods to efficiently transform lignocellulisc biomass into sugars for further biorefining to biofuels. In the near future, through the combination of green solvents, nanoparticle techniques, and functional solid acid catalysts, it can be expected that chemical processes based on the catalysis of biomass will begin to replace petroleum-based processes so that new bio-economic new bio-economic industries will emerge.