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The corncob cheap renewable resources is the most abundant plant straw containing hemicellulose . Acidolysis corn cob preparation of xylose by ultrasound , single male film technology successfully synthesized xylitol . Hydrogenation catalytic processes currently , the method does not need to add a special chemical reagents , low production cost , mild reaction conditions, simple process . In this paper, the hot water treatment to remove the corncob contains a small amount of tannin plant alkaloid , colloids, pigments to improve the purity of xylose . Ultrasound-assisted device homemade corncob acid hydrolysis , respectively, has been systematically studied the influencing factors of the solid-liquid ratio , time , temperature , acid concentration . By the L 9 ( 3 4 < / sup> ) orthogonal experiment was optimized to obtain the optimum parameters of a The ultrasound assisted corncob extract xylose . The experiments showed that : when the solid-liquid ratio of 1:20 , the time was 40min , the temperature was 70 ° C , the acid concentration of 0.8 % , reducing sugars and xylose extraction rate of 18.1% and 17.6% , respectively . As raw materials, in order to obtain a xylose homemade experimental apparatus , a foamed nickel electrode as the cathode , titanium-based ruthenium dioxide electrode as an anode , by a single cation membrane electrochemical synthesis of xylitol . Focuses on the reaction temperature, reaction time, current , and the pH value of the cathode solution and xylose initial concentration factors . By orthogonal experiment L 16 (4 5 ) has been optimized to obtain the optimum parameters of a single the positive film technology electrochemical synthesis of xylitol . The experiments show that : when the reaction temperature was 60 ° C , the reaction current of 2A , the pH value of 10 , the reaction time of 2h initial xylose concentration of 0.75mol / L xylose conversion rate of 99% . By IR, NMR and carbon spectra of experimental products obtained were characterized the experiment proceeds xylitol purity of 99.4% . Single positive film technology synthesis xylitol kinetic analysis results show that the reaction is first order reaction kinetics ; and single male film electro-reduction reaction mechanism was discussed .
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