A Review of Hydrothermal Biomass Liquefaction: Operating Parameters, Reaction Mechanism, and Bio-Oil Yields and Compositions

Energy & Fuels, Год журнала: 2024, Номер 38(10), С. 8437 - 8459

Опубликована: Апрель 29, 2024

Biomass hydrothermal liquefaction (HTL) is a conversion technology that utilizes high-temperature and high-pressure conditions to convert biomass into liquid fuels chemicals. This review introduces all aspects of HTL from system process parameters reaction mechanism pathways product control methods. First, the effects key such as composition, moisture content, heating rate, temperature, residence time, pressure on characteristics were discussed. Next, studies typical components reviewed. For proteins, lipids, carbohydrates, their mechanisms during explored. Understanding can help deeply understand entire process. In terms catalytic control, properties potential application values main product, including bio-oil, aqueous phase, solid gaseous products, analyzed, methods for It introduced adding additives using catalysts improve characteristics. Finally, challenges technical difficulties faced by discussed, future development direction was prospected.

Язык: Английский

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Kinetic and Thermodynamic Evidence of the Paal–Knorr and Debus–Radziszewski Reactions Underlying Formation of Pyrroles and Imidazoles in Hydrothermal Liquefaction of Glucose–Glycine Mixtures

Energy & Fuels, Год журнала: 2024, Номер 38(4), С. 3343 - 3356

Опубликована: Фев. 3, 2024

We evaluated Paal–Knorr and Debus–Radziszewski reactions as the mechanisms underlying formation of pyrroles imidazoles, respectively, in hydrothermal liquefaction (HTL) via semicontinuous HTL experiments on a glucose–glycine mixture. developed cheminformatic-based reaction pathways for range feedstock pH (2–12), temperatures (280–370 °C), times (2–60 min). The were validated using transient concentration reacting compounds assessed reversible power-law kinetics, Arrhenius equation, Maxwell relation Gibbs free energy. assessment informed exothermicity both proposed their activation under acidic conditions with (1) succinaldehyde amino acid/ammonia (2) α-dicarbonyls, formaldehyde, precursors, respectively. Endothermic amidation exothermic decarboxylation followed reactions, producing amide- alkyl-substituted imidazoles biocrude an aqueous-phase coproduct. Moreover, C–C coupling series Wittig olefination Hoesch involving dicarboxylic acid imidazole, fumaronitrile, ylide precipitated polypyrrole azepine- azocine-embedded imidazole hydrochar. Meanwhile, neutral alkaline feedstocks presented transition from alkali-catalyzed (e.g., endothermic Maillard between pyruvaldehyde pyrazines oxazoles) to acid-catalyzed reaction) at longer than 10 min due significant acetic decomposition carbohydrate protein monomers. This study proved that mechanism N-heterocycles varied pH.

Язык: Английский

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Direct and Two-Stage Hydrothermal Liquefaction of Chicken Manure: Impact of Reaction Parameters on Biocrude Oil Upgradation

ACS Sustainable Chemistry & Engineering, Год журнала: 2024, Номер 12(10), С. 4300 - 4313

Опубликована: Фев. 27, 2024

Hydrothermal liquefaction (HTL) provides advantages to traditional methods (e.g., landfilling and composting) convert wet biomass waste agricultural residue) into energy-rich biocrude oil (bio-oil) nutrient-rich aqueous phase. The challenge associated with these feedstocks lies in their high N O contents. These heteroatoms are fixed bio-oil produced from direct-HTL, making it infeasible as a drop-in fuel due the low calorific value. To address challenges for chicken manure, this study evaluated two thermochemical conversion approaches: (1) direct-HTL (2) two-stage process of hydrothermal carbonization (HTC) followed by HTL. second scenario aimed extract most oxygenates phase, producing C-rich stage (i.e., HTL). Experiments were conducted at different temperatures (160–350 °C), reaction times (30–60 min), feedstock pHs (4–9). Acidic conditions achieved adding acetic acid catalyst, whereas natural pH manure was around 9. revealed that properties improved processing acidic = 4–5 HTC 190 °C 30 min HTL 300 min. Due reduced contents, higher heating value increased 32–33 (direct-HTL) 37–38 MJ/kg (two-stage). Nonetheless, overall C recovery decreased ∼35 ∼20% compared direct-HTL. This shows trade-off between removing many possible maximizing bio-oil. A mechanistic underlying degradation mechanisms (dehydration, decarboxylation, denitrogenation) along inhibition Maillard under environment.

Язык: Английский

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A Review of the Valorization of Dairy Industry Wastes through Thermochemical, Biological, and Integrated Processes for Value-Added Products

Food Science of Animal Resources, Год журнала: 2025, Номер 45(2), С. 375 - 408

Опубликована: Янв. 17, 2025

The dairy industry is a significant player in the food industry, providing essential products such as milk, cheese, butter, yogurt, and milk powder to meet global population's needs. However, industry's activities have resulted pollution, with heavy waste generation, disposal, effluent emissions into environment. Properly handling residues major challenge, up 60% of total treatment cost processing unit allocated management. Therefore, valorizing useful presents advantage for industry. Numerous studies proposed various approaches convert products, including thermochemical, biological, integrated conversion pathways. This review an overview these identifies best possible method by-products. research up-to-date information on recovery value-added from waste, biogas, biofertilizers, biopolymers, biosurfactants, focus integrating technology environmental sustainability. Furthermore, obstacles prospects valorization been presented. valuable resource developing deploying technologies, it also opportunities this field.

Язык: Английский

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Reaction Mechanism and Kinetics of Hydrothermal Liquefaction at Sub- and Supercritical Conditions: A Review

Biomass, Год журнала: 2025, Номер 5(1), С. 9 - 9

Опубликована: Фев. 7, 2025

Hydrothermal liquefaction (HTL) technology has garnered immense research interest due to its potential convert wet biomass into petroleum-like biocrude. Understanding the reaction mechanism and kinetics of HTL is crucial for understanding process better, estimating yields, scaling up. On other hand, mechanisms largely depend upon feedstock composition parameters HTL. However, literature lacks an in-depth analysis concerning biocrude yield product distribution a single multi-feedstock scenario. This review focuses on various biomolecular components lignocellulosic biomass, proteins, lipids in under sub- supercritical conditions. Furthermore, kinetics, effect conditions mechanisms, are explored. The findings agree that temperature retention time follow inverse relations high yield. A heating rate recommended higher avoid cracking recombination processes. solvent/feedstock ratio, depending composition, was favored optimum In addition, catalysts solvents, especially organic effectively contribute towards yield, even up 70%. Heterogeneous reusability improved quality. Also, hydrothermal co-liquefaction (multi-feedstock) use improving debated. detailed discussion revealed reactions normally first-order law. Finally, authors outline pointers future industrial upscaling.

Язык: Английский

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Kinetics and thermodynamics of paracetamol synthesis via hydrothermal amidation of hydroquinone by ammonium acetate employing Cu-V-W/Kaolinite catalyst

Chemical Engineering Science, Год журнала: 2025, Номер unknown, С. 121734 - 121734

Опубликована: Апрель 1, 2025

Язык: Английский

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Fast pyrolysis of agricultural residues: Reaction mechanisms and effects of feedstock properties and microwave operating conditions on the yield and product composition

Journal of Analytical and Applied Pyrolysis, Год журнала: 2023, Номер 175, С. 106217 - 106217

Опубликована: Окт. 1, 2023

Fundamental understanding of the pyrolysis process plays an indispensable role in valorization wastes and development novel sustainable technologies. This study introduces a approach by investigating reaction mechanisms involve Microwave-Assisted Fast Pyrolysis (MAFP) to unveil thermal decomposition agricultural residues: pecan nutshell (NS), sugarcane bagasse (SB), orange seed (OS) biomasses. The holistic for these biomasses was analyzed based on final chemical compositions yields bio-oil, biochar biogas correlated microwave processing conditions feedstock's composition. findings revealed that bio-oil is enhanced at moderated energy (<5 GJ/t) as result endothermic reactions such heterolytic fragmentation, Maccoll elimination, Friedel-Craft acylation, Piancatelli rearrangement methoxylation. maximum yield protein-rich biomass due selective heating (Paal-Knorr pyrrole synthesis, Baeyer-Villiger oxidation, Maillard reaction, ring conversion γ-butyrolactone). formation attributed repolymerization aromatic aldehydes, hydrocarbons, amines, ethers, well dehydroxymethylation dealkylation processes. provides comprehensive several using pyrolysis, establish bases effective waste management.

Язык: Английский

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Kinetic and thermodynamic evidences of the Diels-Alder cycloaddition and Pechmann condensation as key mechanisms of hydrochar formation during hydrothermal conversion of Lignin-Cellulose

Chemical Engineering Journal, Год журнала: 2023, Номер 480, С. 148116 - 148116

Опубликована: Дек. 19, 2023

Язык: Английский

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Hydrochar fractionation and composition in batch and continuous hydrothermal liquefaction

Biomass and Bioenergy, Год журнала: 2024, Номер 183, С. 107166 - 107166

Опубликована: Март 18, 2024

Understanding differences in hydrochar characteristics batch and continuous hydrothermal liquefaction (HTL) is crucial determining suitable valorisation routes for this byproduct, given its high nutrient load carbon sequestration potential. This study thoroughly characterised from HTL at 300, 325 350 °C, elucidating their main shedding light on the operational parameters causing them. For purpose, a bench-scale unit with in-line solids separation was commissioned. It possible to differentiate primary secondary char infer formation mechanism. The results showed that yields were higher (24–26%) than (primary secondary) (15–19%). In both reactions, temperatures led chars lower nitrogen contents. ash content of hydrochars chars, revealing separator effectively removed inorganic impurities reaction conditions produced cleaner biocrude. distribution products biocrudes more contaminated by Na, K Fe, while biocrudes, only Fe detected. Moreover, less migrated HTL, indicating removing inorganics may reduce formation. Batch presence oxygenated nitrogenated compounds, had share alkanes alkenes. These imply reactions not serve as indicators, terms characteristics, upscaling industrial plants.

Язык: Английский

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Comprehensive review of hydrothermal liquefaction data for use in machine‐learning models

Biofuels Bioproducts and Biorefining, Год журнала: 2024, Номер 18(5), С. 1782 - 1798

Опубликована: Май 21, 2024

Abstract Hydrothermal liquefaction is a new, sustainable pathway to generate biogenic liquids from organic resources. The technology compatible with wide variety of resources such as lignocellulosic resources, waste, algae, and sewage sludge. chemistry complex predictions yields are notoriously difficult. Understanding modeling hydrothermal currently mostly based on simplified biochemical analysis product yield data. This paper presents large dataset 2439 experiments in batch reactors that were extracted 171 publications the scientific literature. data include composition fiber content composition, proteins, lipids, carbohydrates, ash. experimental conditions recorded for each experiment well reported yields. objective this make database available community. analyzed machine‐learning tools. results show there no consensus techniques, procedures, There many inconsistencies across literature should be improved by Machine‐learning tools allow generation reliable production application field. Given accuracy data, overall precision prediction an extrapolation new can expected around 10%.

Язык: Английский

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