Transformation of glucose into added value compounds in a hydrothermal reaction media

Hydrothermal CO 2 reduction using biomass derivatives as reductants

“…The main by-product obtained from monosaccharides and disaccharides were acetic and lactic acids, in different proportions. That is in agreement to the mechanisms previously described [26,35,40]. However, the similarities in the composition of the by-products do not allow discerning differences in the reaction pathway.…”

“…These intermediates can be then oxidized [34]. The differences observed can then be related to the fact that glucose splits into three C2 molecules (glycolaldehyde) whereas fructose splits into two C3 molecules (glyceraldehyde and pyruvaldehyde) [26,[35][36][37][38], or dehydrates to one 5-HMF molecule. It can be noticed that three times the yield obtained for glycolaldehyde is significantly higher than the sum of the yields for glyceraldehyde and pyruvaldehyde (Figure 1).…”

“…Water can act as acidic and basic catalyst as well as environmentally benign solvent. Following this approach, biomass has been converted into a wide range of intermediates and/or valuable products, such as lactic acid, acetic acid, 5-hydrozymethylfurfural (5-HMF), phenol and vanillin, among others [22][23][24][25][26][27], and many of these reactions involve oxidations. Therefore, the combination of both hydrothermal processes, biomass conversion and CO 2 reduction in one-pot reaction, would provide an attractive and sustainable approach for the valorisation of lignocellulosic residues and the decrease of CO 2 atmospheric emissions by integrating this process in the main CO 2 producers, such as power and industrial factories.…”

Hydrothermal liquefaction of blackcurrant pomace and model molecules: understanding of reaction mechanisms

“…For instance, Cantero, et al 49 reported a total conversion of glucose in 40 seconds at 300 C. Yu-Wu, et al 50 showed similarly that glucose undergoes fast degradation above 250 C. The complete conversion of glucose was also detected by Castello et al 51 aer a few seconds of residence time at 400 C. In the absence of NaOH, hydrothermal conversion of monosaccharides produces mostly water-soluble organic molecules, and an important amount of char (approximately 40 wt% of the initial mass). The addition of NaOH strongly inuences the conversion, notably by increasing the bio-oil yield and reducing the char yield.…”

Supercritical water processes: Future prospects

“…The hydrolysis of glucose to glycolaldehyde was achieved at 400ºC and 23 MPa with a residence time of 3 s; glycolaldehyde selectivity at those conditions was 75% w•w -1 [73]. The reactions of fructose were analyzed in combination with glucose.…”