resumo
The isomerization of aldo-saccharides to keto-saccharides is an important transformation in biomass conversion processes. The use of eco-friendly heterogeneous catalysts for these reactions is most attractive, albeit good catalytic stability continues a challenge. The as-synthesized Aveiro-Manchester material number 4 (AM-4, Na-3(Na,H)Ti2O2[Si2O6](2),2H(2)O) possessed isomerization activity, but limited stability. This versatile precursor material was modified to meet superior performances in the base-catalyzed isomerization of the monosaccharides d-glucose and d-xylose, and the disaccharide d-cellobiose, at 100 degrees C. Different alkali and alkaline-earth metals were introduced into AM-4, which influenced the catalytic properties. The Mg-containing material was the most stable, leading to 27 % fructose yield from d-glucose, 41 % cellobiulose from d-cellobiose and 39 % xylulose from d-xylose isomerization, at 2 h reaction.
palavras-chave
LACTIC-ACID DERIVATIVES; GLUCOSE ISOMERIZATION; ALKALINE-DEGRADATION; CARBON-DIOXIDE; SN-BETA; CELLOBIOSE DECOMPOSITION; LAYERED TITANOSILICATES; LIGNOCELLULOSIC BIOMASS; HYDROTHERMAL SYNTHESIS; XYLOSE ISOMERIZATION
categoria
Chemistry
autores
Antunes, MM; Fernandes, A; Ribeiro, MF; Lin, Z; Valente, AA
nossos autores
agradecimentos
This work was developed within the scope of the project CICECOAveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The positions held by M. M. A. and A. F. were funded by national funds (OE), through FCT, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of article 23 of the Decree-Law 57/2016 of 29 August, changed by Law 57/2017 of 19 July.