| There are many shortages in the hydrolysis technology of conventional producing sugar with lignocellulose.The main shortages are environment pollusion and equipment erodibility, and these make people to have to look for a new method. Plasma technology, a high-tech, has many advantages if applied in the hydrolysis of corn stalk to prepare single-carbohydrate compound is a specific application of this technology. In this paper, the important scientific problems are studied in the process of the hydrolysis of corn stalk using plasma for the preparation of single-carbohydrate compounds, mainly including the following aspects:1. The approach of hydrolysis of corn stalk is studied to prepare carbohydrate under the condition of micro-stream discharge plasma. Hydrolysis products of corn stalk and its main components-model compounds of cellulose, hemicellulose and lignin under the conditions of plasma were characterized and analyzed. The result shows that the corn stalk powder can be further hydrolyzed to sugar products in the absence of oxidation and non-burning case and, advoiding the conventionally complicated pre-processing and additives adding. Cellulose and hemicellulose in the corn stalk are the major contributors to produce sugar products. Lignin can't produce the sugar products in the experimental conditions. The result showes that the stalk powder which has often been reused as waste can be possibly changed into sugar products even in the absence of acid and alkali, no demand for high temperature and high pressure and without the complex pre-preparation.2. The hydrolysis reaction process is proved suitable to the corn stalk under the condition of micro-stream discharge plasma. The result shows that the formation of sugar products related with the water molecules, but water vapor can not stand alone as a discharge gas. With the increase of electric field strength, power density, power frequency and discharge time, sugar yield increased. The discharge interval frequency's influence on sugar yield is more complicated. Experiments determine the optimum process conditions. Under these conditions: stalk powder's average particle size is 0.2mm; the excitation voltage is 5.0kV; discharge time is 120min; discharge interval is 1.66mm; saturated water vapor flow rate is 0.1L/min under normal pressure and 100℃; pressure is 90kPa; N2 flow rate is 0.5L/min; temperature is 90℃and the power frequency is 10.30kHz, the sugar yield of stalk hydrolysis can reach 51.21%.3. Under the micro-stream discharge plasma condition, the temperature distribution in hydrolysis plasma reaction zone and the thermal effect of corn stalks hydrolysis are studied. The result shows that during the discharge interval within the stalk reaction zone, the arc-temperature presents Gaussian profile. In the course of plasma formation, the arc temperature and the normal temperature show the same trends in the temperature increasing and dropoing processes after ceasing the excitation voltage in the stalk reaction zone.Through the temperture of electrode of with and without corn stalk the reaction heat effect are tested, that is 5.826×103 J/g of exothemic reaction.4. Hydrolysis mechanism of corn stalk under the conditions of micro-stream discharge plasma have been clarified, and a preliminary analysis of its dynamic process. The result shows that under the influence of the electric field force, cornstalk is suspended in the room, it has advantage to the action of the reactive particles that generating in the discharge and cornstalk powder. Further more, stalk crystalline structure and the hydrogen bonds are destructed to break glycosidic bonds, combined with H+ and OH- produced by H2O under the action of plasma is conducive to the formation of simple sugars and other products. This process is an transformation process from the oligomer to the higher crystallinity.
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