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With coal, oil and natural gas and other non-renewable fossil fuel consumption continues to seek non-polluting, renewable alternative energy sources and more important. Enormous reserves of biomass in nature, dilute acid hydrolysis produces xylose, arabinose, glucose, fructose, mannose, xylitol fermentation to produce ethanol and other clean chemical fuels, can effectively mitigate environmental pollution and energy crisis. Secondary fiber paper as a plant fiber material, the domestic use of single mode, low utilization, and reuse of secondary pollution. In view of this, this article from the chemical point of view of environmental protection and energy shortages, waste acid hydrolysis saccharification for ethanol from fermentation were studied in order to achieve the comprehensive utilization of waste, reduce environmental pollution. By orthogonal contrasts secondary fiber paper and virgin fiber eucalyptus wood hydrolysis characteristics found in secondary fiber waste paper as raw sugar yield was significantly higher than in eucalyptus wood chips as raw material for the hydrolysis. Then, the secondary fiber paper dilute acid hydrolysis saccharification single factor experiments carried out to explore the hydrolysis temperature, H 2 SO 4 concentration, time, liquid-solid ratio and different inorganic acids (H 2 SO 4 , H 3 PO 4 , HNO 3 ), the catalyst (FeSO 4 , CuSO 4 , Al 2 (SO 4 ) 3 < / sub>) on the effect of hydrolysis, to get the maximum reducing sugar yield was 46.45%. Finally, by HPLC and GC / MS of sulfuric acid hydrolyzate monosaccharides and furfural, carboxylic acid and other components for the qualitative analysis; using FT-IR and X-ray diffraction after hydrolysis time of different crystallinity and waste residue radical structural changes were analyzed, crystallinity increased first and then decreased. Hydrothermal method using glucose as a raw carbon material prepared, and using a carbon material is introduced into the sulfonation of a-COOH,-OH,-SO 3 H group, a sulfonated solid acid was obtained carbon . Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray diffraction of the prepared catalysts were phases and structural characterization; evaluation with an acid value of the reaction temperature solid acid sulfonation conditions , the reaction time and the solid-liquid ratio (carbide: amount of sulfuric acid) were optimized to obtain maximum acid value 1.580mmoL (NaOH) / mL; use of the sulfonated carbon paper for the saccharification of the solid acid catalyst can be effectively saccharification of waste paper, the maximum yield of 26.65 percent sugar. However, poor stability of the catalyst, reused three times, due to the loss of surface sulfonic acid groups, reducing sugar yield decreased 20.33%. The catalyst activity can be restored by re-sulfonation. From the cellulose structure, combined with the use of HPLC and GC / MS analysis of the hydrolysis byproducts discussed mechanism of the hydrolysis of cellulose hydrolysis pathway. Findings generated by hydrolysis of cellulose oligosaccharides and monosaccharides (glucose-based), glucose by ring opening, dehydration and polymerization reactions generate further hydroxymethyl furfural, furfural, levulinic acid and other small molecules. Model using the seaman at different times at different temperatures reducing sugar yield obtained data were obtained by the method of least squares linear fitting kinetic parameters at different temperatures, the model can well fit the experimental data. Using the Arrhenius equation for the linear fit to strike the paper hydrolysis activation energy, activation energy is 36.3kJ/mol. In sulfuric acid mass fraction of 4%, temperature 190 ℃, time 40min, liquid-solid ratio 15 (ml / g), the co-catalyst (FeSO 4 ) 1% in the case of waste paper as raw material liquid water solution . At a temperature of 28 ℃, rotation speed 150r/min, 10% inoculum conditions, using Saccharomyces cerevisiae (CICC1001) to take on the hydrolyzate fermentation ethanol were studied, investigated the growth of bacteria, strain tolerance, domesticated species , neutralized hydrolyzate over processing and cocatalyst (FeSO 4 ) yield of ethanol, to obtain the highest yield of ethanol was 20.01g / L. The research projects of the utilization of waste paper utilization seek a new way, in order to eliminate pollution and ease the energy crisis of purpose, specific to the industrial production remains to be further research and development.
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