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As coal, oil reserves declining in recent years, the rapid increase in oil prices, growing concern and attention of countries on environmental issues, the conversion of cellulose utilization is considered to be an effective way for the development of sustainable energy and green chemicals. However, most of the cellulose resources could not be effectively utilized, therefore, further efficient conversion of cellulose to obtain a high value-added fine chemical products with a special performance feature has become the focus of attention and research scientists hotspot. Microcrystalline cellulose preparation of small molecules such as formic acid and glycolic acid oxidation degradation of organic compounds for the purpose of Metalloporphyrins catalyzed O2 oxidation microcrystalline cellulose reaction in the the aqueous NaOH reaction medium, the system, the effects of various reaction influence factors on the reaction, the preliminary study of the reaction mechanism of metal porphyrin-catalyzed oxidative degradation of microcrystalline cellulose under alkaline conditions. 1, using GC-MS, HPLC-MS, HPLC methods such as the oxidation product of the microcrystalline cellulose in the qualitative and quantitative analysis. The study found that the major product of the oxidation of the metal porphyrin O2 microcrystalline cellulose to formic acid and glycolic acid, in addition to the product of gluconic acid, lactic acid, acetic acid, and levulinic acid. By optimizing the chromatographic conditions, microcrystalline cellulose oxidation products HPLC quantitative analysis methods, the method of high accuracy and good reproducibility. Synthesized a series of water-soluble and non-water-soluble metal porphyrin catalysts and molecular oxygen oxidation Catalytic Performance degradation the microcrystalline cellulose preparation of formic acid and glycolic acid were studied, found TSPPFeCl catalytic properties in the reaction system best. 3, the system examines the reaction time, a different kind of catalyst, reaction temperature, amount of catalyst, the oxygen pressure, the amount of the base to be used, kind of alkali and other factors on the degradation of metal porphyrin catalytically oxidized by O2 microcrystalline cellulose preparation of formic acid and glycolic acid Reaction impact, optimize reaction conditions: 5 mLNaOH concentration of 0.5 mol / L, microcrystalline cellulose 0.5 g, reaction time 6 h, the reaction temperature of 150 ° C, TSPPFeCl 1mg O2 pressure of 2 MPa. Under the reaction conditions, the product is the total yield of 98.20%, with a yield of 20.06% glycolic acid, formic acid in a yield of 49.36%. 4, on the basis of existing cellulose alkaline degradation mechanism and cellulose oxidative degradation mechanism, combined with the previous work in this laboratory, the changes in contrast by the the cellulose surface morphology under different reaction conditions, the system may be the presence of intermediates the means of detection, metal porphyrin degradation of contrast reaction intermediates and reaction process step-by-step investigation of the mechanism of metal porphyrin catalytic O2 oxidation microcrystalline cellulose degradation under alkaline conditions are discussed. The scanning electron microscope (SEM) study found that microcrystalline cellulose, NaOH alkaline conditions under peeling reaction, the crystal structure of macromolecules to be destroyed. DMSO and methylene blue assay of hydroxyl radicals, hydroxyl radicals generated in the reaction system, the presence of a free radical reaction process in the reaction of metal porphyrin O2 oxidized cellulose; reaction intermediate product of the by metal porphyrins catalytic oxidized cellulose System Research, found that the Metalloporphyrins the join makes gluconic acid, lactic acid, acetic acid, levulinic acid intermediates easily oxidized by oxygen is converted to the end product of formic acid and glycolic acid; oxalic acid in the system is very unstable and easily converted to formic acid.
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