Two alternative routes of softwood catalytic oxidative fractionation on cellulose products and fine chemicals are assessed.We suggested to use the process of larch wood peroxide oxidation in the medium acetic acid -water at temperatures 70-100 °C in the presence of soluble catalyst (NH 4 ) 6 Mo 7 O 24 to produce microcrystalline cellulose (35.0 wt% on wood), microfibrillated cellulose (7.5 wt% on wood), nanocrystalline cellulose (3.7 wt% on wood) and low molecular weight organic compounds (20 wt% on wood). The developed process reduces the number of technological stages and increase an environmentally safety of nanocelluloses production from wood, compared to traditional technologies.Another suggested process of softwood (pine and larch) fractionation on vanillin (up to 4.7 wt% on wood) and cellulose (up to 34.6 wt% on wood) is based on wood oxidation by oxygen in water-alkaline medium at temperatures 160-180 °C in the presence of suspended catalyst Cu(OH) 2 . The further acid conversion of cellulose by 2 % H 2 SO 4 at 180 °C produces levulinic acid with the yield up to 9.7 wt % on wood.The integration of the processes of dihydroquercetin and arabinogalactan extraction isolation from larch wood, oxidation of extracted wood by oxygen to vanillin and cellulose in the presence of catalyst Cu(OH) 2 , acid catalyzed conversion of cellulose to levulinic acid and arabinogalactan hydrolysis over solid acid catalyst to arabinose and galactose leads to an increase in the number of target products. FTIR, XRD, SEM, AFM solid state 13 C CP/MAS and chemical methods were used for characterization of cellulose products. Organic compounds were identified by GC, HPLC and GC-MS methods.The two alternative schemes of larch wood catalytic oxidative biorefinery to produce nanocelluloses and fine chemicals have been developed.

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A green one-step catalytic process of obtaining microcrystalline cellulose (MCC) from wood in the medium ''acetic acid-hydrogen peroxide-water'' in the presence 2% wt. sulfuric acid catalyst is described. The influence of wood nature and conditions of the process on the yield, composition and structure of obtained samples of MCC was investigated. For hardwood (aspen wood and birch wood) the minimal content of residual lignin (\1% wt.) was achieved under the following conditions: temperature 130°C, the concentration of H 2 O 2 4% wt., the concentration of CH 3 COOH * 26% wt., liquor ratio of 10 and the process time of 3 h. At these conditions, the degree of delignification of softwood (spruce wood and larch wood) is lower than for hardwood. According to X-ray and FTIR data, the structure of MCC samples obtained from wood is close to that of MCC Avicel and MCC from cotton linter.

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