Tin-Functionalized Wood Biochar as a Sustainable Solid Catalyst for Glucose Isomerization in Biorefinery

Abstract

This study tailored a novel engineered biochar as a solid catalyst for glucose isomerization by pyrolyzing Sn-functionalized wood waste under varying hypothesis-driven selected conditions (i.e., 650, 750, and 850 °C in N2 and CO2 atmosphere). The results showed that properties of biochar support (e.g., porosity and acid/base property) and chemical speciation of Sn were highly related to their catalytic performance. Variations in pyrolysis temperature and feed gas modified the porous structure and surface functionality of biochar as well as the valence state of doped Sn on the biochar. For the N2 biochars, higher pyrolysis temperature enhanced the fructose yield yet had trivial effect on the selectivity, where 12.1 mol % fructose can be obtained at 150 °C and 20 min using biochar produced at 850 °C. This was plausibly attributed to the increased fraction of amorphous Sn structures and metallic Sn that were more reactive than its oxide form. At the pyrolysis temperature of 750 °C, the use of CO2 increased the surface area by 40%, enlarged the pore volume from 0.062 to 0.107 cm3 g–1, and enriched the amorphous Sn structures compared to those for N2 biochar. This probably accounted for the better catalytic performance of CO2 biochar than that of N2 biochar (∼50% and 100% enhancement in fructose yield and selectivity, respectively). The Sn-biochar catalysts may have promoted glucose isomerization via both the Lewis acid and Brønsted base pathways. This study paves a new way to design biochar as a sustainable and low-cost solid catalyst for biorefinery applications.

Review on Activated Carbons by Chemical Activation with FeCl3

“…An excessive amount of FeCl 3 can more intensely catalyze the activation reaction, especially at high activation temperatures, resulting in pore merging and therefore in a reduction of the porosity of the resulting activated carbon [82]. Besides, higher amounts of FeCl 3 can result in larger particles of iron oxides, which can act as a template for the formation of mesopores and/or precipitate in the carbon matrix, altering porous development [83,84]. Similarly, Diaz et al [68] obtained the maximum surface area at an impregnation ratio equal to 2.0 (in a 1.0-3.0 range) when activating grape seed hydrochars.…”

Termite Resistance of a Fast-Growing Pine Wood Treated by In Situ Polymerization of Three Different Precursors

“…Regarding the PW treated with PMMA, there were prominent peaks at 1725 cm −1 (C=O bonds in carboxylic groups from lignin), 1445 cm −1 (stretching vibrations and deformation of C-O bonds), 1245 cm −1 , 1145 cm −1 and 1030 cm −1 (C-O bonds and deformation of the C-H bonds in guaiacyl units from lignin), which are associated with the presence of the PMMA in the inter-and/or intra-cellular spaces of the PW, and certain reactions with its lignin [41,42]. According to Zeng and co-workers, this polymer does not present high toxicity, since the combustion products generated by PMMA burning are carbon monoxide and carbon dioxide [29].…”

Tailored design of graphitic biochar for high-efficiency and chemical-free microwave-assisted removal of refractory organic contaminants

“…The higher molar ratio of (O+N)/C of the ABC-900C (0.200) compared to ABC-900N (0.096) indicated an improved hydrophilicity and polarity in CO2. In particular, the ABC-900C contained a much higher oxygen content (20.3 wt.%) than the other three biochars, probably because of CO2 induced carbon oxidation during cooling inside the tube furnace after pyrolysis [47]. The zeta potential of the OBC-900s was negative (-18.8 --12.6 mV) in contrast to the positively charged surfaces of the ABC-900s (2.64 -6.73 mV), which can be ascribed to the higher metal (i.e., Ca, K, Mg, Na, Fe, and Al) content in the former (Table 1).…”