Pyrolysis Products Of Cellulose Research Articles

Predicting biochar properties and pyrolysis life-cycle inventories with compositional modeling

Biochar, formed through slow pyrolysis of biomass, has garnered attention as a pathway to bind atmospheric carbon in products. However, life cycle assessment data for biomass pyrolysis have limitations in data quality, particularly for novel processes. Here, a compositional, predictive model of slow pyrolysis is developed, with a focus on CO2 fluxes and energy products, reflecting mass-weighted cellulose, hemicellulose, and lignin pyrolysis products for a given pyrolysis temperature. This model accurately predicts biochar yields and composition within 5 % of experimental values but shows broader distributions for bio-oil and syngas (typically within 20 %). This model is demonstrated on common feedstocks to quantify biochar yield, energy, and CO2 emissions as a function of temperature and produce key life cycle inventory flows (e.g., 0.73 kg CO2/kg poplar biochar bound carbon at 500 °C). This model can be adapted to any lignocellulosic biomass to inform development of pyrolysis processes that maximize carbon sequestration.

Identification and Parametrization of Key Factors Affecting Levoglucosan Emission During Solid Fuel Burning.

Levoglucosan (LG) is a pyrolysis product of cellulose and hemicellulose at low combustion temperatures. However, LG release cannot be determined only by considering the contents of cellulose and hemicellulose exclusively due to the complexity of combustion processes and the physical-chemical properties of the fuel. This study detected the emission factors (EFs) of LG from 22 different solid fuel samples (including coal and biomass) by considering 18 different fuel properties and five combustion parameters. The average LGEFs during solid fuel burning varied in a range of 0.03-136 mg kg-1, with a magnitude difference of 1-4 orders. While the variations in cellulose (59.5-368 mg g-1) and hemicellulose (73.5-165 mg g-1) contents of fuel samples were only one- to 6-fold. A short combustion duration (<150 min) and a medium combustion temperature (200-400 °C) influenced by volatile and ash contents are crucial for the generation and accumulation of LG. A random forest coupled with the Akaike information criterion stepwise regression model successfully explained 96% of the total LG emission variation using three variables (ash content, cellulose content, and modified combustion efficiency). The ash content promoted coke formation and LG chain cracking by increasing the pyrolysis temperature and is considered the most important factor. The alkali metal in ash can reduce the energy barrier of intramolecular ring contraction reactions and inhibit the dehydration reactions, which led to additional heat being utilized by the competitive pathways of LG formation. This study provided a method to address the parametrization and release mechanisms of combustion source emissions.

Deep eutectic solvent degumming of hemp fiber: Key factors influencing fiber property and its mechanism

In order to remove non-cellulosic materials from the surface of hemp fiber for potential application in textile industry, a DES (choline chloride: urea, 1:2)- alkali H2O2 (DES- alkali H2O2, DAHD) hemp fiber degumming method was established. The changing regularity of DES treatment on the degumming effect of hemp fiber under different operational conditions (temperature, time and bath ratio) were fully investigated. The properties of purified fibers and the mechanism of degumming were systematically analyzed using several test methods. Chemical composition showed that treated fibers have higher cellulose content than alkaline treated ones, whereas removal rate of non-cellulose components reached 53%. The tenacity, length and degree of polymerization (DP) of the treated fiber was increased by 25%, 30% and 20%, respectively compared with traditional alkali degumming. Analysis by Py-GC/MS indicated the major pyrolysis product (LG) of cellulose was increased by 27.77% after DAHD treatment, and the major ester and ketones content was decreased by 1.07% and 11.13% due the removal of hemicellulose, respectively. Results from 2D NMR revealed that cleavage of β-O-4′ linkages significantly occurred and β-5′ linkages were all removed. The G-type lignin was further degraded than the S-type in DES-alkali H2O2 degumming system. Besides, DES still has enough degumming effect after repeated utilization. This study provides an potential practical method for hemp fiber extraction, which is characterized by high fiber quality, low energy consumption, eco-friendly and high efficiency.

Effect of Fe on the pyrolysis products of lignin, cellulose and hemicellulose, and the formation of carbon nanotubes

In response to severe climate change on a global scale, a shift from fossil fuels to renewable energy is proposed, leading to the high utilization of biomass resources. The current study examined the characteristics of the pyrolysis products of lignin, cellulose and hemicellulose using different Fe contents, and carbon nanotubes (CNTs) were successfully prepared under conventional pyrolysis conditions. The results showed that the addition of 10% Fe significantly increased the content of H2, CH4, and CO in the pyrolysis gas and inhibited the release of CO2. The addition of 10% Fe inhibited the decomposition of lignin surface functional groups and promoted the decomposition of hemicellulose surface functional groups. At the same time, diffraction peaks due to carbon deposition can be observed on the surface of Fe powder. Lignin biochar contained a large number of pores, and the number of pores increased with an increase in the added Fe. The existence of CNTs was observed in the Fe of cellulose corresponding to a small quartz boat, and a mechanism for the preparation of CNTs by chemical vapor deposition using cellulose as raw material was proposed.

Making hybrid mixture explosions a common case

Explosions of gas-dust hybrid mixtures have long been considered as particular cases encountered in specific industrial contexts. However, it should be reminded that during the explosion of an organic powder, the presence of a hybrid mixture composed of the dust itself and its pyrolysis gases is compulsory. On these premises, an experimental study to determine the role of cellulose pyrolysis products (gaseous, condensable and solid) on the global phenomenon is presented. Hybrid mixture explosion tests were exploited to carry out the investigation. The G-G furnace and the 20 L sphere were employed. Several experimental strategies were chosen to demonstrate the impact of pyrolysis reaction on the explosion of organic powders: i) the fuel equivalence ratio of the reactive mixture (case 1), or ii) the mass of reactants (case 2) were respectively kept constant, iii) the effects of water vapor, char and tar were tested. They were next compared to identify the most suitable one. The two first experimental approaches lead to significantly different results: only case 2 keeps the maximum explosion pressure almost constant, but maximum rate of pressure rises and deflagration index greatly decrease when the pyrolysis gases concentration decreases, which highlights the importance of the pyrolysis reaction on the explosion kinetics. It should also be stressed that the maximum explosion severity is not obtained for the pure gases but when a small dust content is added. The same evolution is observed when a small amount of char is introduced to pyrolysis gases, which underlines the influence of the radiative transfer. Adding small amounts of tar to cellulose tends to increase its explosion severity. However, this impact is less than that generated by the addition of pyrolysis gases.

Green Drug Discovery: Novel Fragment Space from the Biomass-Derived Molecule Dihydrolevoglucosenone (CyreneTM)

Biomass-derived molecules can provide a basis for sustainable drug discovery. However, their full exploration is hampered by the dominance of millions of old-fashioned screening compounds in classical high-throughput screening (HTS) libraries frequently utilized. We propose a fragment-based drug discovery (FBDD) approach as an efficient method to navigate biomass-derived drug space. Here, we perform a proof-of-concept study with dihydrolevoglucosenone (CyreneTM), a pyrolysis product of cellulose. Diverse synthetic routes afforded a 100-membered fragment library with a diversity in functional groups appended. The library overall performs well in terms of novelty, physicochemical properties, aqueous solubility, stability, and three-dimensionality. Our study suggests that Cyrene-based fragments are a valuable green addition to the drug discovery toolbox. Our findings can help in paving the way for new hit drug candidates that are based on renewable resources.

Characterization of the degradation products of lignocellulosic biomass by using tandem mass spectrometry experiments, model compounds, and quantum chemical calculations.

Biomass-derived degraded lignin and cellulose serve as possible alternatives to fossil fuels for energy and chemical resources. Fast pyrolysis of lignocellulosic biomass generates bio-oil that needs further refinement. However, as pyrolysis causes massive degradation to lignin and cellulose, this process produces very complex mixtures. The same applies to degradation methods other than fast pyrolysis. The ability to identify the degradation products of lignocellulosic biomass is of great importance to be able to optimize methodologies for the conversion of these mixtures to transportation fuels and valuable chemicals. Studies utilizing tandem mass spectrometry have provided invaluable, molecular-level information regarding the identities of compounds in degraded biomass. This review focuses on the molecular-level characterization of fast pyrolysis and other degradation products of lignin and cellulose via tandem mass spectrometry based on collision-activated dissociation (CAD). Many studies discussed here used model compounds to better understand both the ionization chemistry of the degradation products of lignin and cellulose and their ions' CAD reactions in mass spectrometers to develop methods for the structural characterization of the degradation products of lignocellulosic biomass. Further, model compound studies were also carried out to delineate the mechanisms of the fast pyrolysis reactions of lignocellulosic biomass. The above knowledge was used to assign likely structures to many degradation products of lignocellulosic biomass.

A fast and simple extraction method for analysing levoglucosan and its isomers in sediments by ion chromatography tandem mass spectrometry.

The ability to trace current and past biomass burning events is important for understanding the links between human activity, fire frequency, and climate. One method of tracing biomass burning is to measure the concentrations of certain monosaccharides anhydrides (MAs), specifically levoglucosan (LEV) and its isomers, mannosan (MAN) and galactosan (GAL), which are products of cellulose and hemicellulose pyrolysis. This work presents a simple extraction method allowing for the rapid, sensitive, and selective determination of MAs in sediments. MAs detection was performed using suppressed ion chromatography with electrospray - triple-stage quadrupole tandem mass spectrometry (IC-TSQ-MS). The extraction method involves ultrasound probe sonication using water as the solvent. Extraction time, amplitude, and sonication mode were optimised. Recoveries higher than 86% for all MAs tested were achieved by applying 70% amplitude in continuous mode for 60 s. Analytical performance of the method included instrumental LODs of 0.10, 0.12 and 0.50 μg L-1 for LEV, MAN and GAL, respectively. No carryover issues, no matrix effect and no co-elution of targeted MAs with other sugars likely present in sediments samples were observed. The developed extraction method was further validated by the analysis of LEV and MAN in NIST® 1649b urban dust reference material and the resulting concentrations were in excellent agreement with previously reported values. MAs quantification in 70 lake sediment samples were carried out with concentrations found to range from 0.009 to 0.390 μg g-1 for LEV and from 0.009 to 0.194 μg g-1 for MAN. Plotting MAs concentrations versus approximate sediment age allowed the reconstruction of recent fire events impacting two locations in the Central Highlands of Tasmania, Australia.

Fast Pyrolysis of Cellulose and the Effect of a Catalyst on Product Distribution.

Fast pyrolysis of microcrystalline cellulose (MC) was carried out by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The effects of temperature, time, and a catalyst on the distribution of the pyrolysis products were analyzed. The reaction temperature and time can significantly affect the types and yields of compounds produced by cellulose pyrolysis. A pyrolysis temperature of 500-600 °C and pyrolysis time of 20 s optimized the yield of volatile liquid in the pyrolysis products of cellulose. In all catalytic experiments, the relative contents of alcohols (1.97%), acids (2.32%), and esters (4.52%) were highest when K2SO4 was used as a catalyst. HZSM-5 promoted the production of carbohydrates (92.35%) and hydrocarbons (2.20%), while it inhibited the production of aldehydes (0.30%) and ketones (1.80%). MCM-41 had an obvious catalytic effect on cellulose, increasing the contents of aldehydes (41.58%), ketones (24.51%), phenols (1.82%), furans (8.90%), and N-compounds (12.40%) and decreasing those of carbohydrates (5.38%) and alcohols (0%).

Pyrolysis of cellulose with cathode materials recovered from spent binary and ternary lithium-ion batteries

This paper reported a novel study on the kinetics and products of cellulose pyrolysis with two common-used cathode materials of LiCoO2 (LCO) and LiNi1/3Co1/3Mn1/3O2 (LNCMO) recovered from spent binary and ternary lithium-ion batteries (LIBs). The addition of cathode material decreased the temperature of maximum decomposition rate, which was transferred to a lower temperature following the order of Cel + LCO (366 °C) < Cel + LNCMO (368 °C) < Cel (372 °C). Transition metal oxides present in the cathode materials were reduced into metallic states. The addition of LCO with a higher activity than LNCMO could reduce the activation energy of cellulose pyrolysis from 141 kJ/mol to 112 kJ/mol as the distributed activation energy model (DAEM) method used. In addition, both LCO and LNCMO showed excellent catalytic performance in converting anhydrosugars to hydrocarbons (e.g., long-chain alkanes). In the addition of LNCMO, the content of anhydrosugars reduced from 35% to 8%, whereas the content of hydrocarbons increased from 2% to 52%. Compared with LCO, LNCMO resulted in a higher content of hydrocarbons, which was mostly caused by its considerable catalytic effect in transformation of furans and light oxygenates to olefins and aromatics through the decarboxylation reactions. Therefore, LCO and LNCMO could be used as catalysts for biomass pyrolysis in terms of activation energy reduction and products upgrading.

Understanding cellulose pyrolysis under hydrogen atmosphere

The product distributions of cellulose pyrolysis under different pressures, temperatures, and atmospheres were investigated using a high-pressure micropyrolyzer to clarify the pyrolysis reaction mechanism of cellulose decomposition with hydrogen. EGA-MS results shows that the increase in hydrogen pressure prolonged the second stage of cellulose pyrolysis, which was dominated by decarboxylation. Pyrolysis products of cellulose under helium mainly included levoglucosan, furfural, and acids, while cellulose hydropyrolysis mainly produced C5-C7 ketones, besides small amount of alcohols, aromatics and aliphatic hydrocarbons, and even small amount of phenolics. Carbon yield of ketones was as high as 27.2% from cellulose hydropyrolysis under 2.5 MPa hydrogen and 500 °C. The yield of liquid products and non–condensable hydrocarbons increased with elevated hydrogen pressure. The formation mechanisms of aromatics, phenolics, aliphatic hydrocarbons, aldehydes, ketones, and alcohols under hydrogen atmosphere were discussed. Acetaldehyde was produced by acids through a HDO reaction. C5-C7 chain ketones and cyclic ketones were generated by furfural through HDO and hydrocracking reactions. The Diels–Alder reaction to generate aromatics was enhanced by increasing pyrolysis temperature under hydrogen atmosphere. The reaction network of cellulose hydropyrolysis was also proposed.

Tailoring ZSM-5 zeolite porosity and acidity for efficient conversion of municipal solid waste to fuel

Municipal solid waste contains essential building blocks of transportation fuel but is often deposited into landfills. Available conversion processes are still in their infancy; thus, requiring foundational knowledge to control reaction pathways and transform waste macromolecules into desired products. Active, robust, and low-cost catalysts with highly accessible active sites are needed for selective cleavage of certain bonds. The rapid deactivation and diffusion limitations are the major challenges to date which can be controlled by the catalyst pore structure and acidity. In this paper, we developed novel mesoporous ZSM-5 catalysts to maximise levoglucosan conversion, the dominant product of cellulose pyrolysis, into furfural. The concentration of levoglucosan dropped from 12.1% to 3.8% over the mesoporous ZSM-5. Furthermore, the pyrolysis of plastic materials that existed in the waste provided supplementary hydrogen, which synergistically contributed to the hydrodeoxygenation of some compounds like 5-hydroxymethylfurfural and 4-methyl-1,2-Benzenediol. The total amount of non-oxygenated compounds over the mesoporous catalyst reached 77% compared to 59.7% in non-catalytic pyrolysis based on 13 C NMR results. The integration of 13 C NMR and GC-MS results provided an effective tool in identifying key reaction pathways and linking that to the catalyst's textural and acidic properties. • Co-pyrolysis of biomass and polyethylene was catalysed by core-shell hierarchical ZSM-5. • The conversion of levoglucosan, the dominant product from cellulose, reached 68.3% over meso-ZSM-5. • Desired compounds including aliphatic C–C and hydrodeoxygenated products were obtained. • Accessible zeolite active sites were produced due to mesoporous networks enabling conversion of bulky sugar compounds.

Catalytic pyrolysis of cellulose and chitin with calcined dolomite – Pyrolysis kinetics and products analysis

This work comparatively investigated the pyrolysis characteristics and products of cellulose and chitin with/without the calcined dolomite. The apparent activation energy (Ea) of chitin was much lower than that of cellulose due to the difference of chemical structure. The calcined dolomite had a high catalytic activity in reducing the Ea of biomass pyrolysis. Ea was decreased from 161.91 KJ/mol to 145.49 KJ/mol for the cellulose pyrolysis, while it was decreased from 144.67 KJ/mol to 138.43 KJ/mol for the chitin pyrolysis. In the presence of calcined dolomite, the pyrolysis products were upgraded. The conversion of anhydrosugars into small-molecular compounds (e.g., ketones, alcohols, aldehydes, light hydrocarbons) was enhanced during the cellulose pyrolysis. More organic-N compounds (e.g., acetamidos, N-heterocycles) and other small-molecular components (e.g., ketones, hydrocarbons) could be generated during the chitin pyrolysis. In summary, the calcined dolomite showed good performance in cracking large-molecular compounds to small-molecular compounds during the pyrolysis of biopolymers.

Volatile-char interactions during biomass pyrolysis: Effect of char preparation temperature

In this study, the effect of char preparation temperature on the interactions between cellulose volatiles and acid-washed sawdust char was investigated experimentally on a fixed-bed pyrolysis system. The results indicated that significant volatile-char interactions did exist at the pyrolysis temperature of 500 °C as evidenced by the great changes in the composition and distribution of pyrolysis products. The oxygen-containing functional groups as well as the aromatic ring systems in the char both acted as active sites during the volatile-char interactions. The changes in chemical structure of biochar caused by the different preparation temperatures would notably affect the final products of cellulose pyrolysis. Meanwhile, the acid-washed sawdust char was still found to participate in the reaction process, lower temperature chars would have higher reactivities, and an obvious weight loss of char was also observed after interactions. In addition, volatile-char interactions significantly increased the yields of non-condensable gases, especially those of CO and CO2, while decreased the yield of condensable vapors. The introduction of biochar into cellulose pyrolysis could promote the ring scission of pyranoses as well as the decarbonylation/decarboxylation and dehydration reactions, thus caused the yields of anhydrosugars and monoaromatic compounds decreased and the yields of light ketones and acids increased.

Laboratory studies of fresh and aged biomass burning aerosol emitted from east African biomass fuels – Part 2: Chemical properties and characterization

Abstract. There are many fuels used for domestic purposes in east Africa, producing a significant atmospheric burden of the resulting aerosols, which includes biomass burning particles. However, the aerosol physicochemical properties are poorly understood. Here, the combustion of eucalyptus, acacia, and olive fuels was performed at 500 and 800 ∘C in a tube furnace, followed by immediate filter collection for fresh samples or introduction into a photochemical chamber to simulate atmospheric photochemical aging under the influence of anthropogenic emissions. The aerosol generated in the latter experiment was collected onto filters after 12 h of photochemical aging. 500 and 800 ∘C were selected to simulate smoldering and flaming combustion, respectively, and to cover a range of combustion conditions. Methanol extracts from Teflon filters were analyzed by ultra-performance liquid chromatography interfaced to both a diode array detector and an electrospray ionization high-resolution quadrupole time-of-flight mass spectrometer (UPLC/DAD-ESI-HR-QTOFMS) to determine the light absorption properties of biomass burning organic aerosol constituents chemically characterized at the molecular level. Few chemical or UV–visible (UV: ultraviolet) differences were apparent between samples for the fuels when combusted at 800 ∘C. Differences in single-scattering albedo (SSA) between fresh samples at this temperature were attributed to compounds not captured in this analysis, with eucalyptol being one suspected missing component. For fresh combustion at 500 ∘C, many species were present; lignin pyrolysis and distillation products are more prevalent in eucalyptus, while pyrolysis products of cellulose and at least one nitro-aromatic species were more prevalent in acacia. SSA trends are consistent with this, particularly if the absorption of those chromophores extends to the 500–570 nm region. Upon aging, both show that resorcinol or catechol was removed to the highest degree, and both aerosol types were dominated by loss of pyrolysis and distillation products, though they differed in the specific compounds being consumed by the photochemical aging process.

Synthesis of Functionally and Stereochemically Diverse Polymers via Ring-Opening Metathesis Polymerization of Derivatives of the Biomass-Derived Platform Molecule Levoglucosenone Produced at Industrial Scale

The commercially available, abundant and homochiral cellulose pyrolysis product levoglucosenone (LGO) together with the readily derived isolevoglucosenone (isoLGO) form, in a stereoselective manner...

Initial pyrolysis mechanism and product formation of cellulose: An Experimental and Density functional theory(DFT) study

In this paper, analytical pyrolyzer coupled with a gas chromatography–mass spectrometry set-up (Py-GC/MS) and density functional theory(DFT) theory was used to reveal the initial pyrolysis mechanism and product formation mechanism of cellulose pyrolysis. We demonstrated an experimentally benchmarked molecular simulation approach that delineates pyrolysis process of cellulose. Experimental results indicated that the cellulose pyrolysis products mostly incorporate levoglucosan (LG), glycolaldehyde (HAA), 5-hydroxyfurfural (5-HMF), and the like. The constituents of fast pyrolysis products of cellulose and cellobiose demonstrated the identical trend, although the contents of certain products are different. Laying the foundation of experimental analysis, the reaction pathways of four categories of cellulose pyrolysis were outlined using DFT theory; the pathways are those of generating LG, HAA, and 5-HMF and the dehydration reaction in the process of cellulose pyrolysis. Also, by comparing the energy barriers of various reactions, the optimal pathway of different reactions were summarized. The deduced cellulose pyrolysis reaction pathway opened up new ideas for studying the pyrolysis behavior of cellulose.

Unveiling the pyrolysis mechanisms of cellulose: Experimental and theoretical studies

Biomass pyrolysis is a renewable technology for the production of bio-oil and chemicals. The present study aims to develop a fundamental and plausible model for cellulose pyrolysis. The product formation characteristics of cellulose pyrolysis were investigated via Py-GC/MS and TGA-FTIR spectroscopy. The density functional theory method was employed to calculate the energy barriers of different pathways, and the formation and interaction mechanisms of the three most abundant components, levoglucosan, hydroxyacetaldehyde, and pyruvaldehyde, were compared. Levoglucosan is most likely formed via a concerted mechanism; hydroxyacetaldehyde can be formed from C1-C2 and C5-C6 via a ring-opening reaction and dehydration, while pyruvaldehyde is produced via ring opening, followed by dehydration and retro-aldol reactions. Related to the variations in products, the formation of hydroxyacetaldehyde and pyruvaldehyde was suggested to compete with that of levoglucosan. Based on the experimental and theoretical results, a plausible reaction scheme was proposed. By accounting for these main reactions, approximately 80% (in relative area) of the products of cellulose pyrolysis were included. This investigation is crucial to downstream process development for biomass and provides guidance for product control.

Initial pyrolysis mechanism of cellulose revealed by in-situ DRIFT analysis and theoretical calculation

Cellulose is one of the major components of biomass. The study on its pyrolysis process will be beneficial to the in-depth understanding of biomass pyrolysis mechanism. In this work, in-situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFT) combined with two-dimensional perturbation correlation infrared spectroscopy (2D-PCIS) was first used to characterize the evolution process of the functional groups in cellulose during pyrolysis. The results showed that the degradation of carbon skeleton was prior to the dehydration of free hydroxyls after the destruction of hydrogen bond networks during pyrolysis. The thermal stability of CO in cellulose followed by the order of glycosidic bond <CO in glucopyranose ring <CO between glucopyranose ring and hydroxyl. Followingly, micro pyrolysis experiment was performed to analyze the pyrolysis products of cellulose at various temperatures. It was found that the rupture of glucopyranose rings to form 2C and 4C products was more difficult than the dissociation of C6 hydroxymethyls, and required higher pyrolysis temperature. Quantum chemistry calculation was further carried out to study the key reaction pathways including dehydration, cleavage of glycosidic bond, ring opening and fragmentation in the initial stage of cellulose pyrolysis. The result showed that the concerted cleavage of glycosidic bond to form LG-end short chain was the most favored with the lowest activation energy. The ring opening of the glucose unit in the chain occurred via the cleavage of C1-O. The formed ring opening product was more likely to degrade via the dissociation of C6 hydroxymethyl compared with the breakage of C2–C3 to form 2C and 4C products. Besides, the dehydration of hydroxyls in glucose units required high energy barriers and was difficult to occur.

Products distribution and generation pathway of cellulose pyrolysis

Pyrolysis was one of the most effective ways for the clean use of biomass and biomass that constitutes a huge annual production. In order better utilize biomass, this study infers the pyrolysis mechanism of cellulose, cellobiose, β-D-glucopyranose and levoglucosan by Py-GC-MS (Pyrolysis-gas chromatography-mass spectrometry) and in-situ infrared spectroscopy. Pyrolysis products of cellulose included dehydrated saccharides, furans, small molecules, furanones, benzenes, and cyclopentanones. The first three categories were the main products. Saccharides had the highest yield in cellulose pyrolysis products. The yield of furans in pyrolysis products of cellobiose was higher than that in cellulose and β-D-glucopyranose. The highest yield of small molecules, such as acetaldehyde and methyl glyoxal, was found in pyrolysis products of β-D-glucopyranose. There was a competitive relationship among the production of saccharides, furans and small molecules in the primary pyrolysis. And the furans and small molecules were also the products of the secondary pyrolysis of saccharides. Combined with in situ infrared analysis, 32 generation pathways of the 27 main products detected from Py-GC-MS were given; this provides a theoretical basis for subsequent research on targeted pyrolysis manufacturing target products.