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Information × Registration Number 0221U102431, 0119U101755 , R & D reports Title Creation of methods for the directed catalytic pyrolysis of biomass in order to obtain functional chiral and aromatic compounds popup.stage_title Head Kartel Mykola T., Доктор хімічних наук Registration Date 02-02-2021 Organization Chuiko Institute of Surface Chemistry of NAS of Ukraine popup.description2  On the silica surface there are two stages of pyrolysis of the adsorbed polysaccharide (stage I - Tmax ~ 300 ° C and stage II - Tmax ~ 380 ° C). Stage I is caused by the transformation of the free segments (loops, tails) of the polymer, Stage II - the segments that are directly connected to the surface. It is established that additional, compared to the condensed state, high-temperature stage of polysaccharide pyrolysis on the silica surface (Tmax ~ 380 ° C) due to the chemisorption of hydroxymethyl groups with formation of grafted ether groups ≡ Si-O-CH2- [Glu-O-] n, result which is the blocking of the involvement of hydroxymethyl groups in the depolymerization process and, as a consequence, the absence of levoglucosan and dianhydro-derivatives pyrolysis products. It is shown that changing the amount of adsorbed polysaccharide on the silica surface can change not only the quantitative but also the qualitative composition of the pyrolysis products. In particular, reduce or increase the yield of the pyran or furan compounds. The kinetic parameters of the formation of a number of pyran and furan derivatives were calculated (maximum reaction rate Tmax, reaction order n, activation energy E ≠, overexposure factor ν0, entropy of activation dS та) and proposed possible mechanisms for the formation of compounds of pyranoglucan, other compounds. Product Description popup.authors Kulyk Tetiana V. Nastasienko Nataliya S. Palyanitsya Borys B. popup.nrat_date 2021-02-02 Close