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Our country and the world are facing the problem of the shortage of energy. Bioenergy is the use of bio-renewable raw materials and the production of energy; fiber is the world's largest renewable resource, the use of cellulosic bioenergy production with the greatest potential. China has abundant corn cob, bagasse, wheat bran, straw and other cellulose-based natural resource rich agricultural and forestry waste. This method uses ethylated monosaccharides, oligosaccharides and sugar alcohols modified to liquefaction, studied the synthesis conditions and the combustion performance; on this basis, using corncob, bagasse, wheat bran and other agricultural and forestry waste degradation was prepared liquid energy. The main conclusions are: (1) 1-chloroethane the amount of sodium hydroxide, temperature, time four-factor of sucrose, mannitol, glycerol, ethyl reaction of the same tendency. Glycerol ethyl optimum reaction conditions were: a chloroethane and NaOH dosage (molar ratio of hydroxyl and raw materials) were 1.25:1 and 1:1, the temperature of 120 ℃, time of 8h. In this condition, the yield of ethyl 14.61g/10mL glycerin glycerol. (2) the use of sucrose, mannitol and etherification agent chloroethane successfully used to achieve a one-step reaction of the liquefaction oligosaccharides and sugar alcohols, glycerol and glycerol ethylated also changed and combustion properties of fluidity. Ethylated by the composition of the product analysis, the case of the degree of substitution: Sucrose 6-7 ethylated hydroxy-substituted product of the most abundant, representing 70.39% of the total, only full-ethylation of sucrose 5.26%; ethylated 4-5 mannitol degree of substitution of the product accounted for 79.54% of the total; ethyl glycerin 2 and 3, the degree of substitution of the product accounted for 62.57% and 31.36%. By measuring its partial combustion properties found ethylated sucrose, mannitol, glycerol can be individually combustion, but also with ethanol and bio-diesel combustion. By comparison with the national standards for biodiesel and found ethylated sucrose, mannitol, glycerol can be used as bio-energy use. (3) corncob, bagasse, wheat bran according to 1:6 (w / v) added 1% (v / v) sulfuric acid, at 180. C for 30min after acid hydrolysis, the raw material dry weight were reduced by 47.8%, 38.8%, 42.8%. Wherein the acid solution with a solution in the vast majority of reducing monosaccharide solution corncob acidolysis pentose is mainly xylose and arabinose, the two content of 75.35%; bagasse hydrolyzate acid content of 78.59 Xylose %, wheat bran acid hydrolyzate arabinose and xylose accounted for 97.16%. The acid hydrolysis solution oligosaccharides contain only small amounts. (4) acid hydrolysis solution were added sugar content equal to 0.1% (w / w) sodium hydride, boron hydride, after 30min, the sugar was added after the hydrogenation, sodium hydroxide, tetrabutylammonium bromide (TBAB) and a chlorine ethane After the reaction, the product obtained etherification. After analysis, the etherification reaction product pentose sugar alcohol compounds with higher levels of the three etherification reaction product pentose sugar alcohol compounds, respectively, of the total 54.2%, 68.9%, 75.36%. Five-carbon sugar alcohol is ethyl substituted hydroxyl number of mostly concentrated in three or more, corn cob, bagasse, wheat bran raw number of hydroxyl-substituted in the 3 and above levels reached 33.91%, respectively, 52.52 %, 42.08%. The six-carbon sugar alcohol compounds the number of hydroxyl groups are replaced mostly 3-5. The resulting corn cob, bagasse, wheat bran acid hydrolyzate etherification product by testing, you can burn alone, but also with ethanol and bio-diesel combustion and found that it can also be used as bio-energy.
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