Main Biomass Components Research Articles

Diversity of the Starch Granule Morphology of Several Types Cassava (Minihot esculenta Crantz)

Cassava (Manihot esculenta Crantz), which is commonly called singkong is multipurpose crop that can be processed as food, feed and other cassava-based bioproduct. Potential application of cassava starch is determined by the properties of starch as the main component of cassava tuber biomass. The size of the cassava starch granules is different for each variety due to genetic and the environment factors in which it grows. The size of the starch granules affects the application of the starch. This study aimed to determine the shape and diameter of the starch granule in several types of cassava through microscopic analysis. The shape and the size of the 62 starch samples tested was varied. The starch granules shape was dominated by spheres form. The diameter of cassava starch granules ranged from 2.016 ± 0.015 µm – 3.318 ± 0.045 µm. The highest diameter was Tidung1.2 and the lowest was Tidung 2.2.

Thermal degradation of cellulose and coal gangue based on lumped reaction model and principal component analysis

The effect of cellulose on pyrolysis characteristics of coal gangue was studied based on TG-FTIR experiment. Cellulose with different mass ratios is added to coal gangue. Synergistic effect between cellulose and coal gangue on mass loss was observed in this study. CG1CEL1 and CG1CEL3 samples have mutual promotion effect between CG and CEL. Conversely, the inhibitory effect of CG3CEL1 between CG and CEL was evident at high temperature. The reaction mechanism of coal gangue and cellulose co-pyrolysis based on lumped reaction model was determined. Furthermore, the comprehensive influencing factors of coal gangue and cellulose co-pyrolysis were analyzed by principal component analysis. There is little research on the influence mechanism of cellulose, the main component of biomass, on the pyrolysis of coal gangue. This paper is of great significance to clarify the mechanism of co-pyrolysis of biomass and coal gangue. This study provides a basis for revealing the influence mechanism of cellulose on coal gangue pyrolysis, which accelerates the process of carbon neutralization. This can promote resource disposal of coal gangue by reduction, so as to reduce environmental pollution and improve the utilization rate of fossil energy.

Molecular interaction between ionic liquids with lignin dimers

Biomass is an alternative to using fossil fuels. It is made up mainly of agricultural and forestry residues. The main components of biomass are cellulose, hemicellulose, and lignocellulose (Li, 2015). Due to the structure of lignin and its chemical properties, chemical products based on aromatic compounds and fuels can be obtained (Sangha, 2012). However, its recalcitrant nature and the difficulties encountered in effecting depolymerization, coupled with its low solubility with common organic solvents, result in conversion processes that use extreme conditions of temperature, pressure and acidity (Hicks, 2011). Ionic liquids (ILs) are advantageous solvents for the conversion of lignin to a value-added product due to their ease of dissolving it. In this work we studied the interaction of nine different ILs, formed between the [EMIM+], [BMIM+] y [HMIM+] and the anions [BF4-], [OAc-] and [Cl-], whose use has been reported in the industrial pretreatment of lignocellulose (For, 2007), and lignin dimersderived from coniferyl alcohol (one of the basic units of lignin), which contain the characteristic β-O-4 bond of the biopolymer. Born-Oppenheimer (DMBO) quantum molecular dynamics calculations were performed with the BIOVIA 2016 Materials Studio program (BIOVIA, Dassault Systèmes, 2017), varying the pressure and temperature conditions with the micro canonical assemblies NVE and NVT. The results obtained with the NVE and NVT assemblies show that for some LIs the interaction is favorable and for others there is a great destabilization of the Lignin-IL interaction.

Effect of hydrothermal and hydrothermal oxidation pretreatment on the physicochemical properties of biofuel pellet

The effects of hydrothermal pretreatment with and without H2O2 addition on the properties of the resulted biofuel pellets prepared from cotton stalk (CS) and Chinese fir wood sawdust (WS) were mainly studied in the paper. Based on the changes of three main components (hemicellulose, cellulose and lignin) of biomass during the pretreatment process, the relaxation density, compressive strength, heating values (HVs), and combustion characteristics of the resulted pellets were analyzed to evaluate the feasibility of the utilization as biofuel pellets. The results indicate that the hydrothermal pretreatments with and without H2O2 addition are beneficial to the quality of the resulted biofuel pellets. Particularly, the hydrothermal pretreatment with H2O2 addition, namely the hydrothermal oxidation pretreatment can significantly alleviate the pretreatment severity of the high-strength biofuel pellet preparation. H2O2 addition promotes the decomposition of hemicellulose and cellulose during the pretreatment. Compared with CS, WS is more sensitive to the pretreatment, especially hydrothermal oxidation pretreatment. The crystallinity index and the cellulose content of the biomass sample both increase firstly and then decrease with the increasing pretreatment temperature. In the study, the pretreatment temperature for the biofuel pellets with the best mechanical properties is 230 °C for the hydrothermal process and 200 °C for the hydrothermal oxidation process, respectively. The HVs of the resulted biofuel pellet increases with the increasing pretreatment intensity and the suitable pretreatment can improve the combustion characteristics of the resulted biomass. The mechanical properties of the pretreated biofuel pellets were positively correlated with the crystallinity and the content of the cellulose. HVs of WS pellets is higher than CS pellets, with the better mechanical properties. The cellulose is more favorable for the improvement of the combustion properties of the biomass sample than the hemicellulose and lignin. In addition, HVs and the compressive strength of all the biofuel pellets prepared from the pretreated biomasses meet the Sweden Standard (SS18 7120) and the Ministry of Agriculture of China standard (NY/T1878–2010), respectively.

Ionic liquid dissolution utilized for biomass conversion into biofuels, value-added chemicals and advanced materials: A comprehensive review

Lignocellulosic and algal biomass feedstocks are the most plentiful and cost-effective renewable sources of biofuels (sugar, bioethanol, biodiesel, and bio-oil), value-added chemicals (organic compounds), and advanced materials (hydrogels and composites). The lignin, cellulose, and hemicellulose complex's recalcitrance, which leads to ineffective conversion into valuable compounds, is one of the most significant challenges in biomass valorization. Some ionic liquids (ILs) have been shown to be efficient decomposers of lignocellulosic and algal biomass. In reality, ILs offer a unique green alternative compared to harmful volatile organic solvents and severe process conditions. Enhanced productivity in the conversion of biomass feedstocks could result from advancements in IL-based pretreatment technologies. The capability of the different types of ILs for conversion, as well as the impact of different properties and operating parameters, are comprehensively reviewed and discussed in this paper. The known methods for the dissolution of three main components of lignocellulosic and algal biomass with ILs are also described. Furthermore, the challenges to be addressed when utilizing IL for biomass pretreatment and processing on a commercial scale are highlighted. The significantpromise of ionic liquids for this objective is anticipated to stimulate research and lead to considerable technological advancements in this field.

Valorization of agro-industrial residues for production of commercial biorefinery products

Agro-food industrial residues (AFIRs) are produced in vast amounts around the world. These wastes are commonly called lignocellulosic wastes that are a source of value-added products. Solid-state fermentation (SSF) for bioconversion of lignocellulosic waste, which produces various bioproducts, has economic and environmental advantages. The lignocellulosic compounds are biorenewable and most plentiful resource on earth that can be utilized for manufacturing value-added products. Furthermore, the use of lignocellulosic, starchy, and other agro-industrial by-products in the manufacture of these biomolecules has yet to be thoroughly investigated. As a result, there is a vast opportunity for the development of cost-effective, sustainable biorefining technologies. The main components of lignocellulosic biomass used in biorefineries are cellulose, hemicellulose and lignin. To obtain final biobased products, these components must be processed through a series of procedures that include pretreatments, enzymatic hydrolysis, and fermentation. Biotechnology techniques and process engineering are critical in developing integrated processes for producing various value-added products from lignocellulosic biomass, including biofuels, biochemicals, bioactive substances, enzymes, and biomaterials. This review focuses on the valorization potential of lignocellulosic, palm oil mill, brewing, and dairy biomass produced as agri-food industrial by-products for developing biobased products in the biorefinery scenario. It is the first review of its kind to include variety of products that can be derived from different wastes encircling all the pros and cons of current technology and focusing on future improvements.

Catalytic Conversion of Glucose into 5-hydroxymethyl furfural over Spent Dry Batteries as Catalysts

Biomass is a popular renewable carbon source because it has a lot of potential as a substitute for scarce fossil fuels and has been used to make essential compounds like 5-hydroxymethylfurfural (HMF). One of the main components of biomass, glucose, has been extensively studied as a precursor for the production of HMF. Several efforts have been made to find efficient and repeatable procedures for the synthesis of HMF, a chemical platform used in the manufacturing of fuels and other high-value compounds. Sulfonated graphite (SG) was produced from spent dry batteries and utilized as a catalyst to convert glucose to 5-hydroxymethylfurfural (HMF). Temperature, reaction time, and catalyst loading were the variables studied. When dimethyl sulfoxide was utilized as the solvent at 180°C after 3 hours of reaction time, the greatest HMF yield, glucose conversion, and selectivity were attained, with 56.53 %, 97.5 %, and 57.979 %, respectively. This study demonstrates how to manufacture sulfonated graphite with increased catalytic activity for converting glucose to key biobased platform chemicals in a long-term sustainable manner.

Selectivity Control of C-O Bond Cleavage for Catalytic Biomass Valorization

Increasing fossil fuels consumption and global warming have driven the global revolution towards renewable energy sources. Lignocellulosic biomass is the main source of renewable carbon-based fuels. The abundant intermolecular linkages and high oxygen content between cellulose, hemicellulose, and lignin limit the use of traditional fuels. Therefore, it is a promising strategy to break the above linkages and remove oxygen by selective catalytic cracking of C–O bond to further transform the main components of biomass into small molecular products. This mini-review discusses the significance of selectivity control in C–O bond cleavage with well-tailored catalytic systems or strategies for furnishing biofuels and value-added chemicals of high efficiency from lignocellulosic biomass. The current challenges and future opportunities of converting lignocellulose biomass into high-value chemicals are also summarized and analyzed.

Effect of co-liquefaction of lignin and laminaria saccharina on optimization of bio-oil yield

• Co-liquefaction of Laminaria saccharina with lignin is studied. • The synergistic effect is negative in most mild and lignin-rich conditions. • The synergistic effect is positive in severe and lignin-poor conditions. • Residence time showed an impact on bio-oil quality. • Co-liquefaction synergistically enhanced the bio-oil quality at specific conditions. Hydrothermal liquefaction (HTL) is a valuable technology to convert and use wet biomass feedstocks. Lignin, waste from the paper industry and the main component of lignocellulosic biomass, is co-liquefied with laminaria saccharina, a commonly available seaweed in Norway. The aim is to conduct statistical analysis and investigate the possibility of increasing bio-oil yield while lowering the char yield through a synergistic effect. The bio-oil and char yields are measured with different operating temperatures, residence times, and blending ratios (mass ratio of laminaria saccharina to the total mass) to find out the optimized process conditions for better outputs statistically. Response surface methodology (RSM) with a Box Behnken design methodology is used to optimize the liquefaction yields of laminaria saccharina, lignin, and the different blends of the two biomasses. The results explicitly revealed that the biomass blend's optimal bio-oil and char yields are 0.2513 (w/w 0 ) and 0.1791 (w/w 0 ) respectively at 573 K, 20 min with the blending mass ratio of 0.2. The synergistic effects on the bio-oil yield are detected at comparatively severe reaction conditions. According to the RSM, residence time does not affect bio-oil and char yields as much as the operating temperature and the blending ratio. Nevertheless, temperature, residence time, and blending ratio have different impacts on the functional groups. The temperature increase has helped increase the alcohol and phenolic compounds production while the residence time consumes the C-O bonds. The increase of laminaria saccharina mass ratio in the feedstock has improved the phenolic compounds, long-chain aliphatic hydrocarbons, carboxylic acids, ketones, aldehydes, and esters in the bio-oils. Co-liqueafctio has produced bio-oil with significantly lower N content than from bio-oil produced from laminaria saccharina liquefaction.

Characteristics and evolution of heavy components in bio-oil from the pyrolysis of cellulose, hemicellulose and lignin

Three main components of biomass were pyrolyzed individually in a closed reaction system at 500–700 °C for 60s and 90s. Then bio-oil heavy compounds were further analyzed with Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) and Kendrick mass defect (KMD) analysis. The evolution paths of heavy compounds for the different pyrolysis stages were proposed. It was found that the sugars and phenolic-like species in heavy compounds were the most active substances during secondary reactions. Moreover, the rising temperature promoted this secondary reaction of phenolic-like species as the decrease in their abundances growing from 13% to 54%, while contrarily inhibited it for hemicellulose as the decrease in their abundances changing from 44% to −2%. The lignin-derived lipids and unsaturated hydrocarbons that generated in the secondary reactions increased with rising temperature. KMD analysis showed that the heavy compounds of cellulose and hemicellulose prefer homologous evolution during pyrolysis, while those of lignin had more complex evolution paths like cracking and recombination.

Enzymatic hydrolysis of plant raw materials: state and prospects

Plant raw materials are practically an inexhaustible natural resource, since they are constantly renewed in the process of plant photosynthesis, which determines the prospects for their use for industrial processing in various ways, including hydrolytic. The main biopolymer components of plant biomass in terms of their quantitative content are polysaccharides, the hydrolytic processing of which by acidic or enzymatic hydrolysis leads to the formation of monosaccharides and various products obtained from them. This review of scientific literature analyzes theoretical concepts and the current state of research on the development, improvement and prospects for the use of enzymatic hydrolysis of plant raw materials. The efficiency of this process and the composition of the resulting products largely depend on the features of the supramolecular structure of cellulose, the content of hemicelluloses and lignin in the raw material, the balance and activity of the cellulase complex of enzymes. It is shown that the main directions of development and improvement of the processes of enzymatic hydrolysis of plant raw materials at present are the production and use of more effective strains of microorganisms that produce highly active enzymes, the directed creation of complex enzymes (hydrolyzing not only cellulose, but also hemicellulose, as well as destroying lignin), the development of methods for pretreatment of raw materials to increase the reactivity of cellulose and remove lignin and improve the processes of fermentolysis.

Investigating (Pseudo)-Heterogeneous Pd-Catalysts for Kraft Lignin Depolymerization under Mild Aqueous Basic Conditions

Lignin is one of the main components of lignocellulosic biomass and corresponds to the first renewable source of aromatic compounds. It is obtained as a by-product in 100 million tons per year, mainly from the paper industry, from which only 2–3% is upgraded for chemistry purposes, with the rest being used as an energy source. The richness of the functional groups in lignin makes it an attractive precursor for a wide variety of aromatic compounds. With this aim, we investigated the Pd-catalyzed depolymerization of lignin under mild oxidizing conditions (air, 150 °C, and aqueous NaOH) producing oxygenated aromatic compounds, such as vanillin, vanillic acid, and acetovanillone. Palladium catalysts were implemented following different strategies, involving nanoparticles stabilized in water, and nanoparticles were supported on TiO2. Significant conversion of lignin was observed in all cases; however, depending on the catalyst nature and the synthetic methods, differences were observed in terms of selectivity in aromatic monomers, mainly vanillin. All these aspects are discussed in detail in this report, which also provides new insights into the role that Pd-catalysts can play for the lignin depolymerization mechanism.

Recovery of waste biomass: pyrolysis and characterization of sugarcane residues and their bio-oils

The production and disposal of agro-industrial waste can be detrimental to the sustainable development of natural and energy resources, when this waste is not properly handled. The use of these residues is a desire not yet reached by Brazil, so it is necessary to search for alternatives to minimize this problem. Among the thermochemical processes for converting biomass, pyrolysis (thermal degradation of any solid organic material in the partial or total absence of an oxidizing agent) is a promising tool for obtaining bio-oil, which can be used as a fuel or chemical supply. In addition to bio-oil, the pyrolysis process generates biochar and pyrolysis gases. In this work, the results confirmed the potential of sugarcane in the thermochemical process, on the other hand, thermogravimetric analyzes demonstrated that there is a relationship between the main components of biomass (lignin, hemicellulose and cellulose) and the components present in bio- oil. The bio-oils obtained have a chemical composition rich in oxygenated compounds, especially phenols, which are important industrial inputs, in addition to ketones and aldehydes.

Production of Arthrospira (Spirulina) platensis Enriched in β-Glucans through Phosphorus Limitation

(1) Background: Arthrospira (commonly known as Spirulina) is an edible cyanobacterium that is produced worldwide as a food supplement owing to its high nutritional value. Arthrospira displays strong potential as an important ingredient in the development of novel functional foods. Polysaccharides from Arthrospira are biologically active compounds and hence there is interest in producing biomass rich in carbohydrates. (2) Methods: A. platensis was cultivated under different degrees of phosphorus limitation in order to trigger the accumulation of carbohydrates. The biomass was then characterized in terms of its content of α- and β-glucans, total dietary fiber and monosaccharide profile. Fourier-transform infrared spectroscopy (FTIR) was used for the rapid analysis of the main biomass components. (3) Results: Phosphorus limitation resulted in an increase in carbohydrates (from 23% up to 65% dry biomass) of which 4–12% (in relation to the dry biomass) was α-glucans and 20–34% was 1.3:1.6 β-glucans, while 1.4:1.6 β-glucans were not detected. Total dietary fibers ranged from 20–32% (of dry biomass), whereas among the carbohydrates, the predominant monosaccharide was glucose (>95%). FTIR performed well when applied as a prediction tool for the main biomass components. (4) Conclusions: Since β-glucans are of particular interest as biologically active compounds, this study demonstrates that phosphorus-limited A. platensis could be a potential ingredient for the development of novel functional foods.

Primary interactions of biomass components during fast pyrolysis

Fast pyrolysis is an industrially attractive method to produce fuels and chemicals from biomass; however, to gain better control over the process, the reactions and interactions between the components and decomposition products need elucidation. This study investigated primary reactions during fast pyrolysis of biomass. Pyrolysis of the three main biomass components (cellulose, hemicellulose and lignin) and their blends was carried out with a micro-pyrolyser connected to a Gas Chromatograph-Mass Spectrometer/Flame Ionisation Detector (GC–MS/FID). The blends of the individual components were prepared in similar proportions to that of native biomass (birchwood) and were pyrolysed at 600 °C for 2 s. The results showed that the two-component blends decrease the production of saccharides to a large extent. This was especially noticeable for levoglucosan when cellulose was mixed with either hemicellulose or lignin. Similarly, in the presence of cellulose, the formation of phenolic compounds from lignin was inhibited by 62 %. However, no differences were found in yields of the main products for the xylan-lignin blend compared to those from the individual components. The yields of volatile products from the cellulose-xylan blend were promoted for a majority of the product categories and were most pronounced for the aldehydes. Furthermore, while the formation of the phenols and saccharides was slightly inhibited for the three-component blend, the aldehydes, ketones and furans showed an increased production compared to the weighed sum of products expected, based on the pyrolysis of the individual components. The native biomass showed a similar trend as the three-component blend in all product categories except for the saccharides, which were inhibited to a large extent. This study provides a better understanding of the interactions occurring between different components during fast pyrolysis of biomass.

Catalytic fast pyrolysis of beech wood lignin isolated by different biomass (pre)treatment processes: Organosolv, hydrothermal and enzymatic hydrolysis

Lignin is one of the three main structural components of lignocellulosic biomass and is considered as the most abundant source of aromatic and phenolic compounds. Lignin is produced as side-stream in the pulp/paper industry or as residue in the production of second-generation bioethanol. More recently, novel biomass fractionation processes in biorefineries have been developed aiming at the production of high quality/purity lignin towards its more efficient down-stream catalytic conversion to chemicals, monomers, and fuels. Within this context, in this work, we studied the thermal (non-catalytic) and catalytic fast pyrolysis on a Py/GC–MS system and a fixed-bed reactor unit of three types of lignin, all originating from the same biomass (beech wood sawdust) but with different isolation processes: organosolv lignin derived by the organosolv pretreatment/fractionation of biomass, surface extracted lignin derived by the mild Soxhlet extraction (with ethanol or acetone) from the hydrothermally (HT) in pure water pretreated biomass, and the enzymatic hydrolysis lignin derived as a lignin-rich solid residue from the enzymatic hydrolysis of the HT pretreated biomass. Conventional microporous ZSM-5 and mesoporous ZSM-5 zeolites (with intracrystal mesopores, ˜ 9 nm) were used as catalysts in the pyrolysis experiments. Both zeolites were very active in converting the initially produced via thermal pyrolysis methoxy-substituted phenols, benzenes and benzaldehydes mainly towards BTX mono-aromatics, such as 1,3-dimethylbenzene/p- and o-xylenes, toluene and trimethylbenzenes, as well as polycyclic aromatic hydrocarbons (PAHs, mainly naphthalenes). The mesoporous ZSM-5 induced higher dealkoxylation reactivity compared to the microporous ZSM-5 leading to higher concentration of BTX aromatics without a consequent increase of PAHs. The pronounced dealkoxylation/aromatization reactivity of both ZSM-5 zeolites resulted to lower yields (but highly aromatic) organic bio-oils (e.g. from 32−35 wt.% to 15−22 wt.%) compared to thermal pyrolysis, increased non-condensable gases (mainly CO, CO2, methane, ethylene and propylene) and formation of relatively low amounts of coke on catalysts (e.g. 3−5 wt.% on lignin) in addition to thermal pyrolysis char. The observed moderate variations in the characteristics of the three types of beech wood lignin, i.e. molecular weight (GPC), S/G ratio, inter-unit linkages (2D HSQC NMR) and elemental composition, did not induce a systematic/substantial differentiation in the thermal and catalytic fast pyrolysis product yields and composition.

Simple and Fast One-Pot Cellulose Gel Preparation in Aqueous Pyrrolidinium Hydroxide Solution-Cellulose Solvent and Antibacterial Agent.

Cellulose is the main component of biomass and is the most abundant biopolymer on earth; it is a non-toxic, low-cost material that is biocompatible and biodegradable. Cellulose gels are receiving increasing attention as medical products, e.g., as wound dressings. However, the preparation of cellulose hydrogels employing unmodified cellulose is scarcely reported because of the cumbersome dissolution of cellulose. In previous studies, we developed the new promising cellulose solvent N-butyl-N-methylpyrrolidinium hydroxide in an aqueous solution, which can dissolve up to 20 wt% cellulose within a short time at room temperature. In this study, we employed this solvent system and investigated the gelation behavior of cellulose after crosslinker addition. The swelling behavior in water (swelling ratio, water uptake), the mechanical properties under compression, and the antibacterial activity against Escherichia coli and Bacillus subtilis were investigated. We have developed a simple and fast one-pot method for the preparation of cellulose gels, in which aqueous pyrrolidinium hydroxide solution was acting as the solvent and as an antibacterial reagent. The pyrrolidinium hydroxide content of the gels was controlled by adjustment of the water volume employed for swelling. Simple recovery of the solvent system was also possible, which makes this preparation method environmentally benign.

Hydroxymethylfurfural as an Intermediate of Cellulose Carbonization.

Invited for this month's cover is the group of Haruo Kawamoto at Kyoto University (Japan). The cover picture shows the carbonization pathway of cellulose via 5-hydroxymethylfurfural as an important intermediate. Thermochemical conversion is one of the promising technologies to convert cellulose, which is the main component of lignocellulosic biomass, into biofuels and biochemicals. Understanding the molecular mechanism of thermal degradation of cellulose is important for developing efficient conversion techniques by controlling the reaction. Read the full text of their Full Paper at 10.1002/open.202000314.

Reaction Characteristics of Organosolv-Fractionation Process for Selective Extraction of Carbohydrates and Lignin from Rice Husks

The organosolv-fractionation process can act as a biorefinery process because it can separate the main components of biomass, such as lignin and hemicellulose, with high purity. The ethanol-based organosolv-fractionation process was applied to separate carbohydrates and lignin from rice husks, and the extraction behavior was observed according to various reaction variables. Various reaction conditions such as different temperatures (150 °C, 170 °C, and 190 °C), reaction times (30 min, 60 min, and 120 min), and ethanol concentrations (40%, 60%, and 80%) were tested while maintaining the solid:liquid ratio (1:10) and sulfuric acid concentration (0.25 wt.%). Two optimal reaction conditions for the target components were chosen: for sugar recovery, 150 °C, 60 min, and 40% ethanol were used as condition 1, and for lignin recovery, 170 °C, 120 min, and 80% ethanol were used as condition 2. Under condition 1, 91.5% of the glucan was preserved in the residual solid, and 75.0% of the xylan was extracted from the liquid hydrolysate. For condition 2, 59.9% of the lignin was recovered. To properly choose and apply the correct fractionation method and conditions, the reaction behavior (such as carbohydrate retention and extraction), lignin solubilization, and precipitation should be carefully considered.

Liquid chemical looping gasification of biomass: Thermodynamic analysis on cellulose

Liquid chemical looping technology is an innovation of chemical looping conversion technology. Using liquid metal oxide as the oxygen carrier during gasification process could prolong the service life of oxygen carrier and improve the process efficiency. In this paper, based on Gibbs minimum free energy method, the thermodynamic characteristics of biomass liquid chemical looping gasification were studied. Cellulose and lignin, the main components of biomass, were taken as the research objects. Bismuth oxide and antimony oxide were selected as liquid oxygen carriers. The results showed that when the temperature increased from 600 °C to 900 °C, the output of H 2 and CO in the products of cellulose gasification increased from 0.5 and 0.3 kmol to 1.3 and 2.6 kmol respectively. Different ratios of oxygen carriers to gasification raw materials had the best molar ratio. The addition of steam in the system was beneficial to the increase of H 2 content and the increase of H 2 /CO molar ratio. Bi 2 O 3 and Sb 2 O 3 with different mass ratios were used as mixed oxygen carriers. The simulation results showed that the gasification temperature of biomass with different mixed oxygen carriers had the same equilibrium trend products. It could be seen from the results of product distribution that the influence of the mixing ratio of Bi 2 O 3 and Sb 2 O 3 on gas product distribution could be neglected. These results could provide simulation reference and data basis for subsequent research on liquid chemical looping gasification.