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Increasing depletion of non-renewable resources such as oil, coal, natural gas, resulting in the world's energy crisis is worsening. Biomass is renewable, zero net carbon emissions, the development and utilization in line with the concept of low-carbon economy, with the in-depth study of new energy, biomass and other renewable resources research and development has become the world today is facing a major issue. In this paper, prepared by coprecipitation MgMOx (M = Cr, Ni, Al, Mn, Zn, Fe) series of binary metal composite oxide catalyst. Microcrystalline cellulose and bagasse as raw material, the autoclave process in hot water under the conditions of catalytic liquefaction process. Meanwhile, the biomass liquefaction of the reaction product is divided into the vapor phase, a water-soluble phase, tetrahydrofuran (THF) was dissolved phase and the residue was purified four parts, the main compound in the composition and the relative content of the water-soluble phase by gas chromatography-mass spectrometry (GC-MS) were analyzed, and analysis of the impact of the liquefaction reaction temperature, time phase product bagasse liquefaction of water-soluble acid, hydroxyl value; using gel penetration chromatography (GPC) tetrahydrofuran solution-phase compounds of molecular weight distribution characterization, and Fourier infrared spectrum (FT-IR) its main characteristic functional groups were analyzed; using elemental analyzer the analysis and characterization of the chemical elements of the liquefaction residue composition and calorific value (HHV). The reaction temperature and time, the ratio of liquid to solid, liquefied atmosphere, catalyst factors such as microcrystalline cellulose, bagasse liquefaction conversion rate and product distribution. The results showed that when the catalyst to the binary metal composite oxide MgMnOx as 250 ° C, 30 min, liquid to solid ratio of 10 conditions, microcrystalline cellulose conversion rate of 96.2%; 270 ° C for 5 min, the liquid-solid a ratio of 10, bagasse conversion was 90.4%, wherein the water-soluble phase yield was 51.5%. When to MgMnOx as a liquefaction catalyst, microcrystalline cellulose aqueous liquefied phase main product of the cyclopentenone and its derivatives, 2 - hydroxy-propionic acid, and a small amount of an acid, an alcohol, an ether, tetrahydrofuran extraction phase mass average molecular weight (Mw ) to 659 g · mol-1; bagasse liquefaction, tetrahydrofuran extraction phase mass average molecular weight of 802 g · mol-1, less catalyst to reduce the 219 G · mol-1. Catalyst for bagasse liquefaction phase yield distribution and water-soluble phase composition has a great influence, to MgMnOx series of composite metal oxide as a catalyst, the aqueous phase product cyclopentenone derivatives, 2,5 - has dione, phenol and derivatives, levulinic acid, p-hydroxy aldehyde, etc.; absence of a catalyst, the liquefied water-soluble phases of furfural and its derivatives 5 - (hydroxymethyl) -2 - furaldehyde. Composite metal oxide the catalyst MgMnOx can effectively promote microcrystalline cellulose, bagasse liquefaction degradation, and environmentally friendly, the results of this study on the catalytic liquefaction of biomass has good reference.
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