Carbohydrate-Derived Hydrothermal Carbons: A Thorough Characterization Study

Abstract

Hydrothermal carbonization (HTC) is an aqueous-phase route to produce carbon materials using biomass or biomass-derived precursors. In this paper, a comprehensive physicochemical and textural characterization of HTC materials obtained using four different precursors, namely, xylose, glucose, sucrose, and starch, is presented. The development of porosity in the prepared HTC materials as a function of thermal treatment (under an inert atmosphere) was specifically monitored using N(2) and CO(2) sorption analysis. The events taking place during the thermal treatment process were studied by a combined thermogravimetric/infrared (TGA-IR) measurement. Interestingly, these inexpensive biomass-derived carbon materials show good selectivity for CO(2) adsorption over N(2) (CO(2)/N(2) selectivity of 20 at 273 K, 1 bar and 1:1 gas composition). Furthermore, the elemental composition, morphologies, degree of structural order, surface charge, and functional groups are also investigated.

Tailoring the porosity of chemically activated hydrothermal carbons: Influence of the precursor and hydrothermal carbonization temperature

“…catalysis, separation science, energy production and storage), is their low surface area and porosity [10]. In the case of monosaccharide derived HTC carbons, this problem has been elegantly overcome by using hard\soft-templating strategies or by addition of structural directing agents [11][12][13].…”

A Review of Hydrothermal Carbonization of Carbohydrates for Carbon Spheres Preparation

“…After the further heat treatment, the carbon content increased from 60 wt% to above 80 wt%, while oxygen contents were correspondingly reduced [40].…”

“…But the surface appeared rougher because of micropore formation. If the heating temperature was too high, carbon spheres linked each other [40].…”

“…Carbonaceous materials derived from pentosebased carbohydrates showed morphological and chemical differences from hexose-based ones [27]. Because furfural was the main dehydration product from pentose-based saccharides, while HMF was the main dehydration product from hexoses-based saccharides [40].…”

Synthesis and Characterization of Carbon Nanospheres Obtained by Hydrothermal Carbonization of Wood-derived and Other Saccharides

“…The CO peak centered at 500C was assigned to the ether decomposition and the CO peak above 550C was contributed to the phenols and quinine [8]. Subsequently at 500°C , the methane peak originated from decomposition of the methylene bridges, which acted as cross-linkers within the HTC carbon framework [9]. Hydrogen on the carbon surface served as chemisorbed water or as surface functionalities (e.g., carboxylic acids, phenolic groups), or was bonded directly to carbon atoms as a part of aromatic or aliphatic structures.…”