Kinetic Study of the Hydrothermal Carbonization Reaction of Glucose and Its Product Structures

Abstract

In order to systematically understand the hydrothermal carbonization reactions and kinetics of glucose at 180 °C, the structures of intermediate and final chemical products were identified, the conversion paths were clarified, and the conversion rates and yields were calculated. By comparing the hydrothermal reaction paths and kinetics of 5-hydroxymethylfurfural (HMF), fructose, and glucose, it is proven that HMF is the most important intermediate and the sole precursor of hydrothermal carbon. The degradation of glucose, fructose, and HMF follows the first-order reaction, and the formation of hydrothermal carbon linearly depends on the conversion of HMF. Approximately 28% of HMF is converted from fructose and ∼72% is from glucose. Also, the hydrothermal reaction time-dependent morphologies and structures of the resulting hydrothermal carbon are compared, and their structures before and after heat treatment are characterized.

Tailoring Rational Crystal Orientation and Tunable Sulfur Vacancy on Metal‐Sulfides toward Advanced Ultrafast Ion‐Storage Capability

“…Based on the previous reports, plentiful aromatic ring of glucose will break and some of them can be hydrolyzed into small‐molecule intermediates with carboxy (−COOH) functional group, such as formic acid (HCOOH), acetic acid (CH 3 COOH), and lactic acid (CH 3 CH(OH)COOH) during the hydrothermal/solvothermal process. [ 22 ] Then, these carboxylic acids will inevitably react with stoichiometric S 2− anions of (Sb 4 S 6 ) n nanoparticles to produce H 2 S at 180 °C, which will bring about abundant S ‐vacancies and S ‐doped carbon matrix in the SS/C and SS/H@C spontaneously. By contrast, in the solvothermal solution of SS@C, the carboxylic acids would directly react with sufficient free S 2− anions released by thiocarbamide instead of taking away S 2− anions of (Sb 4 S 6 ) n nanoparticles, leading to rare S ‐vacancies in SS@C. Notably, besides contributing to improving electrical conductivity, the S ‐vacancies can perform as unsaturated coordination active sites that have strong chemisorption ability to entrap polysulfides.…”

Diverse Applications of Biomass‐Derived 5‐Hydroxymethylfurfural and Derivatives as Renewable Starting Materials

“…[73,74] Recently, it was shown by He et al that HMF is the sole precursor for the formation of thermal hydrocarbons from glucose. [75] At very high temperatures, the ability of HMF to undergo polycondensation and carbonize can be utilized to generate hollow carbon nanospheres (HCNs). HCNs are nanomaterials with particular applications related to their thin shell structures and large internal voids, which allow for unique properties such as low density, high surface area, and gas capture capabilities.…”

“…Recently, it was shown by He et al. that HMF is the sole precursor for the formation of thermal hydrocarbons from glucose [75] …”

Elucidating the Maillard Reaction Mechanism in the Hydrothermal Liquefaction of Binary Model Compound Mixtures and Spirulina

“…Proteins and carbohydrates are two of the major components of all biological organisms and represent a significant portion of biomass and biowaste. , Rich protein biomass such as soy protein produces on average a 25% mass yield of water-insoluble biocrude and around 60% nitrogen recovery in the aqueous phase. ,− The HTL conversion of carbohydrates generates high solid yields and acidic aqueous phases with relatively high concentrations of 5-hydroxymethyl furfural (HMF) and levulinic acid (LA) among other water-soluble intermediates. ,,,,− The Maillard interaction between carbohydrate and protein intermediates might boost the renewable biocrude yields. ,− , Despite the Maillard reaction pathway being well known in the food industry, it is scarcely understood throughout the thermochemical conversion of biomass and its impact on current kinetic models is negligible. ,− …”