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Synergistic effects from fast co-pyrolysis of low-rank coal with lignin via on-line mass spectrometry were explored. Iso-conversional method was used to obtain frequency factor and activation energy of main gaseous products. The morphology evolution of both individual and co-pyrolysis char was analyzed via fractal theory quantificationally. The results indicated that various synergistic effects were found from the distribution and composition of products. CO and CO 2 were the main content of the gaseous products, and the content of CO from lignin increased with the temperature. Lignin promoted the generation of tar and inhibited the formation of gaseous products during fast co-pyrolysis, which reflected different synergistic effects, respectively. Positive synergistic effects were observed from the component proportion of CH 4 as the temperature increasing higher than 600 °C. Kinetic analysis indicated that activation energy for H 2 from lignin and low-rank coal was 32.21 and 59.90 kJ/mol, and higher temperature would be beneficial for H 2 formation. Fractal analysis indicated that lignin promoted the surface morphology of co-pyrolysis char to become more complicated, with the fractal dimension of individual char less than those of co-pyrolysis char. • Synergistic effects from fast co-pyrolysis of low-rank coal with lignin were explored. • The product distribution and change rules during the co-pyrolysis process were studied. • Kinetic parameters about gaseous products were obtained via the iso-conventional method. • Fractal analysis was applied to describe the morphology evolution of co-pyrolysis char. [ABSTRACT FROM AUTHOR]

In this paper, a carbonization process for valid liquid–solid separation and upgrading of coal liquefaction residues was proposed and practiced using batch-type devices. The effect of carbonization times and temperatures on the efficiency of liquid–solid separation and product distributions were investigated using self-prepared liquid–solid mixtures (CSMs) from direct coal liquefaction. It was suggested that the carbonization temperature and blowing gases were essential to the efficient liquid–solid separation in this process, and the carbonization process was characterized by the efficient liquid–solid separation. The n -hexane soluble fractions (HS) can be largely separated from CLMs. It was remarkable that over 0.06–1.50% of HSs can be additionally produced at the higher temperatures (430 °C–500 °C). On the other hand, the obtained semi-cokes (SCs) were mainly characterized as a rich carbon-containing material with high heating values. Some of the SCs were characterized by the better caking property with the caking index ( G ) from 68.5 to 75.2. In addition, it was proved that the caking property of SCs is directly affected by the asphaltenes (ASs) instead of pre-asphaltenes (PAs). [ABSTRACT FROM AUTHOR]

A large number of greenhouse gas emissions have brought a series of environmental problems, so it is urgent to realize efficient conversion of CO 2. The multistage regeneration process of CO 2 chemical looping conversion was established and the process simulation analysis carried out with Aspen Plus. The system's feasibility was verified by simulation and the process needed to provide additional energy input, and the sensitivity analysis of different operating conditions was carried out to provide guidance for subsequent experimental design. Oxygen carrier bauxite residue was modified by acid washing and CeO 2 impregnation, and the reaction characteristics were evaluated via a fixed-bed reactor and on-line mass spectrometry, and the kinetic parameters of the reaction were solved by gas-solid reaction kinetics. The results showed that 12 wt% CeO 2 loading oxygen carrier had the highest yield and average formation rate of CO, which were 6.22 mmol·g−1 and 388.71 μmol·g−1·min−1, respectively. The oxygen carrier conversion (oxygen vacancy utilization) was close to 100% after modification, while that of single bauxite residue oxygen carrier was only 60%. The reaction system conformed to the first-order reaction model, and the activation energy was 33.90 kJ·mol−1. This study provided new insight into chemical looping conversion of CO 2. • Process simulation of CO 2 chemical looping conversion was carried out. • H 2 -TPR and CO 2 -TPO proved that it was feasible to using CeO 2 modified red mud. • 12 wt% CeO 2 /RM after H 2 reduction had the best reaction performance with CO 2. • The kinetic belonged to first-order reaction and kinetic parameter was solved. [ABSTRACT FROM AUTHOR]

A large amount of coal tar residue (CTR) produced in the process of coal coking and tar processing is recognized as hazardous industrial waste with a high carbon content and strong carcinogenic polycyclic aromatic hydrocarbons. Through solvent extraction, CTR can be separated into economically valuable tar and fixed carbon, and waste recycling can be realized. In this paper, a mathematical model of CTR solid-liquid extraction is established based on a diffusion model and experiments, and the mass transfer law, mass transfer equation, and influence of different conditions of solid-liquid separation of CTR from toluene extraction are studied. First, the empirical formula is used to derive the change in the mass transfer coefficient k f outside the particles during extraction, and the k f gradually decreases as the extraction progresses. The particle swarm optimization is used to obtain the best effective diffusion coefficient D eff , inside the particles, which is 9.65 × 10−14 m2/s. The effective diffusion coefficient, D eff , was determined and corrected based on experimental data. A second-order function was fitted to describe the variation of D eff with temperature. MATLAB software was used to solve the model the concentration change law and extraction law during extraction were obtained. According to the model simulation, the influence of different conditions such as agent residue ratio, stirring speed, particle radius, and temperature on the extraction process is calculated. [Display omitted] • The tar diffusion characteristics of CTR particles in toluene solvent were studied. • A mathematical model of CTR solid-liquid extraction was established based on a diffusion model. • Calculate the mass transfer coefficient k f and the effective diffusion coefficient D eff. • Analyze the influence of different conditions on the extraction process. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge (DBD) plasma is used to prepare ternary heterostructured Ru–Co–B oxide catalyst with considerable RuO 2 /CoO/B 20 H 26 O interface and oxygen vacancy (Ov) for enhanced borohydride oxidation reaction. the Ru–Co–B catalyst displayed remarkable electrocatalytic activity and long-term stability Due to the difference in energy band structure at the interface where the charge distribution is not homogeneous, the heterogeneous structure will spontaneously generate a built-in electric field which prompts the interfacial charge transfer. The production of Ov increases its active site and promotes its catalytic activity. While it is used in membrane-less direct borohydride fuel cells (DBFCs), it showed a peak power density of 206 mW cm−2 at room temperature and a remarkable stability of 270 h at a constant current of 20 mA that is superior to commercial Pt/C. [Display omitted] • Heterogeneous catalysts with abundant oxygen vacancies were synthesized by plasma technology. • The use of ruthenium instead of platinum reduces the cost of the fuel cells. • The power density can reach 206 mW cm−2, the stability is greatly improved. • The preparation process does not need high temperature treatment, achieving green color, low energy consumption. [ABSTRACT FROM AUTHOR]

Catalytic CO 2 methanation is a potential solution for conversion of CO 2 into valuable products, and the catalyst plays a crucial role on the CO 2 conversion and CH 4 selectivity. However, some details involved in the CO 2 methanation over the carbon supported Ni catalysts are not yet fully understood. In this work, commercial coal char (CC) supported Ni catalysts were designed and prepared by two different methods (impregnation-thermal treatment method and thermal treatment-impregnation method) for CO 2 methanation. Effects of the preparation conditions (including the thermal treatment temperature and time, the mass ratio of CC:Ni and the preparation method), as well as the reaction temperature of CO 2 methanation, were investigated on the catalyst morphology, reducibility, structure and catalytic performance. Fibrous Ni-CC catalyst is achieved and shows high CO 2 conversion (72.9%–100%) and CH 4 selectivity (>99.0%) during the 600-min methanation process. Adverse changes of the catalyst surface and textural properties, reducibility, particle size and morphology are the potential factors leading to the catalyst deactivation, and possible solutions resistant to the deactivation were analyzed and discussed. The CO 2 methanation mechanism with the CO route was proposed based on the oxidation-reduction cycle of Ni in this work. [Display omitted] • Ni-coal char catalysts are prepared by two methods and used for CO 2 methanation. • Fibrous Ni-based catalyst shows CO 2 conversion >72.9% and CH 4 selectivity >99.0%. • CO 2 methanation mechanism with the CO route is proposed based on redox cycle of Ni. • Potential factors leading to catalyst deactivation and the solutions are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biomass chemical looping gasification was investigated via liquid oxygen carrier. • The apparent activation energies of ICLG of CE, CE/Bi 2 O 3 and CE/Sb 2 O 3 were obtained. • The performances of Bi 2 O 3 and Sb 2 O 3 as liquid oxygen carriers were compared. • The addition of Bi 2 O 3 was beneficial to the chemical looping gasification of cellulose. Using liquid oxygen carriers is an inventive promising alternative to solving the problems of wear and sintering caused by solid oxygen carriers in chemical looping gasification (CLG). Bismuth oxide (Bi 2 O 3) and Antimony oxide (Sb 2 O 3) were selected as liquid oxygen carriers, and the kinetics of liquid chemical looping gasification (LCLG) of cellulose (CE) was analyzed by thermogravimetric analysis. Samples of CE-oxygen carriers were prepared with different mixing ratios, and thermogravimetric experiments were carried out at different heating rates. The apparent activation energies of CE, CE/Bi 2 O 3 -10, CE/Bi 2 O 3 -30 and CE/Bi 2 O 3 -50 were 181.93, 155.72, 179.50, and 170.47 kJ·mol−1, respectively. The apparent activation energies of CE/Sb 2 O 3 -10, CE/Sb 2 O 3 -30 and CE/Sb 2 O 3 -50 were 179.40, 152.89 and 129.55 kJ·mol−1, respectively. The results showed that Bi 2 O 3 could significantly reduce the activation energy of CE gasification, which had better performance as a liquid oxygen carrier than Sb 2 O 3. When the mass fraction of Bi 2 O 3 was 10%, the lowest average activation energy was 155.72 kJ·mol−1. [ABSTRACT FROM AUTHOR]

Coal direct chemical looping gasification (CDCLG) to produce synthesis gas was investigated with Fe-based bimetallic composite oxygen carriers (Fe–M oxides, M = Ba, Ca, Cu, Ni and Co). Thermogravimetric-mass spectrum analysis and fixed-bed tests indicated that reaction between coal and Fe-based composite oxygen carriers via direct contact could not be negligible in the CDCLG process. The contribution of the reaction between the two solid particles to the carbon conversion was estimated. Furthermore, the yields of synthesis gas production were also conducted to evaluate performance for the prepared samples. Of the five investigated Fe-based bimetallic composite oxygen carriers (OCs), Fe–Ni oxides/Al 2 O 3 presented high reactivity with coal and high selectivity for synthesis gas during coal-OC steam gasification, which made it attractive for the CDCLG process. By comparing with the main phases of the Fe-based OCs after cycling and the raw samples before test, it could be observed that there were no significant changes in material phases. Combined with the SEM images of the Fe-based OCs samples, we can conclude that the prepared OCs showed a good heat-resistant property, which was beneficial for keeping a stable performance in the CDCLG experiment. • Five Fe-based bimetallic composite oxygen carriers have been obtained. • Reaction between coal and OCs investigated in the static contact regime. • Fe–Ni oxides/Al 2 O 3 presents high reactivity with coal and selectivity for syngas. [ABSTRACT FROM AUTHOR]

• The simple formula and thermodynamic function calculation method of Wheat straw were constructed. • The pyrolysis reaction system was constructed based on the Wheat straw components. • The effects of pressure and temperature on the thermodynamics of Wheat straw pyrolysis were revealed. • Explore the feasible region of product formation reaction. Given the complexity of the rapid pyrolysis reaction system of wheat straw and the difficulty in product regulation, this paper investigated the feasible range for high-value product formation. It determined the conditions for product regulation of wheat straw pyrolysis through thermodynamic analysis. The research constructed the standard enthalpy of formation Δ H f 0 , standard entropy Δ S m 0 , and standard Gibbs free energy of formation Δ G f 0 of wheat straw molecules. Based on the pyrolysis characteristics of cellulose, hemicellulose, and lignin, which were the main components of wheat straw, 34 reactions were constructed to produce high-valued components such as 2-furfural, acetone, and guaiacol. With Gibbs free energy and equilibrium constant as evaluation indexes, the relationship between the feasible region of the reaction and temperature and pressure at 200–800 °C and 0.1–10 MPa was explored. The results showed that Δ H f 0 was-115.86 kJ mol−1, Δ S m 0 was 66.34 J mol−1 K−1 and Δ G f 0 was-135.64 kJ mol−1. The temperature was conducive to a spontaneous endothermic reaction, whereas pressure was not conducive to a spontaneous reaction. As the pressure increases, the temperature required for spontaneous reaction also increases. At 10 MPa, the thermodynamic temperature at which the reaction of glyoxal and acrolein could proceed spontaneously was increased by 318 °C and 87 °C, respectively. At 0.5 MPa, the range of 3- hydroxy -2- butanone could be spontaneous was 200–388 °C. By adjusting the temperature and pressure, the product's production process could be directed. [ABSTRACT FROM AUTHOR]

Pyrolysis is a clean and efficient technology for the conversion of low-rank coal. Its key product is tar with high value. The complex composition of tar limits its further effective utilization. Although most kinetic models can provide the final distribution of three-phase products in coal pyrolysis, an effective prediction method for the specific composition of tar and gas has not yet been developed. Most numerical models serve to improve the total yield of volatile matter and cannot provide theoretical guidance for the improvement of tar quality or the reduction of carbon emission. Based on the basic assumptions of the CPD (Chemical Percolation Devolatilization) model for product molecules structure and generation mechanism, this paper proposed a more sophisticated method for dividing tar composition, which can achieve the division of light, medium, and heavy fractions of tar components according to boiling point. Light gas composition could be obtained with the combination of FG(Functional Group) submodel. The influence of pyrolysis final temperature, heating rate, and environmental pressure was explored for the yield and distribution of products of 18 coals. The simulation results showed that the total yield of tar was affected by both coal structure characteristics and operating parameters. Under conditions favorable for evaporation, such as low pressure and high temperature, the total yield of tar was positively correlated with the average aromatic core size in coal. Under other conditions, tar release was limited by its volatility. Coal with larger average aromatic core size corresponded to less tar yield instead. The pressure in the operating parameters had the most significant influence on the total yield of tar. The heavy fractions of tar are more sensitive to changes in operational parameters, making working conditions that increase the total yield of tar reduce tar quality. The overall carbon emission of pyrolysis is <1 kg CO 2 /kg tar, which is far lower than the 2–4 kg CO 2 /kg tar and 3–9 kg CO 2 /kg tar of direct and indirect liquefaction processes. Under the conditions of sufficient insulation time and no consideration of secondary reactions, the carbon emission of pyrolysis only depended on the content of carboxyl groups in the precursor functional groups. Therefore, the carbon emission intensity decreased with the increase of coal rank. For the optimization for total tar yield and tar quality, 1 atm pressure and 723–923 K temperature was optimal for low rank coals, while low temperature and heating rate with 10–20 atm pressure or high temperature and heating rate with 45–50 atm pressure were optimal for medium rank coals. For the optimization of light tar yield and tar quality, 6–9 atm pressure was optimal for low-rank coals, and 1–3 atm pressure was optimal for medium-rank coals. • A detailed volatile composition prediction model based on unit division was proposed. • The pressure and heating rate had the maximum and minimum effect on tar yield. • There was a contradictory relationship between tar quality and tar yield. • Total tar and gas yield was related to their average precursor structural unit size. • Compared to other coal-to-oil processes, pyrolysis has lower carbon emissions. [ABSTRACT FROM AUTHOR]

• Pyrolysis properties of tar-rich coal and macerals were analyzed by TG and in situ FTIR. • Vitrinite had higher hydrocarbon potential due to aliphatic chains from in suit FTIR. • Inertinite had poor reaction performance and stronger stability due to more aromatic CH. • Volatile yield depended on hydrogen-rich structures such as aliphatic –CH-, –CH 2 -. • Structural parameters varied with the distribution of functional groups. Tar-rich coal is a high-quality coal-based oil and gas resource, pyrolysis of tar-rich coal is crucial to alleviate the world energy crisis and pressure on oil and gas resources. This paper analyzed pyrolysis characteristics of tar-rich coal and macerals and evolution mechanism of main functional groups by thermogravimetric analyzer and Fourier in-situ infrared spectrometer. The thermogravimetry results showed that when the heating rate was 10 ∼ 40 °C·min−1, inertinite's volatile yield was 25.21 %∼27.27 %, significantly lower than that of tar-rich coal and vitrinite, the average activation energy required for tar-rich coal pyrolysis was 185.63 kJ·mol−1, lower than 360.56 kJ·mol−1 of vitrinite, indicating that inertinite had more macromolecular structure and was not easy to be pyrolyzed and volatilized, volatile was more likely to be generated and liberated in tar-rich coal. The results of in-situ infrared analysis showed that coal mainly contained out-of-plane aromatic CH, C-O-C, aliphatic-CH 3 , –CH 2 , –CH, C = O, –OH and other major functional group structures. Vitrinite contained more aliphatic-CH 2 , –CH 3 , –CH and other aliphatic hydrocarbon structures. Tar-rich coal and vitrinite contained more hydrogen-rich structures such as aliphatic CH and active groups such as free-OH, inertinite contained more ether bonds, C = O and hydrogen bonds, almost no aliphatic hydrocarbons and oxygen-containing active groups, and had stronger structural stability. The results of structural parameter analysis showed that under the same conditions, for vitrinite, the aliphatic chain length and hydrocarbon potential were 1.14 and 2.37, greater than those of tar-rich coal and inertinite. The aromatic degree and aromatic condensation degree were 0.39 and 0.48, lower than those of tar-rich coal and inertinite. The pyrolysis characteristic indexes of tar-rich coal and vitrinite were 90.04 (10-8 %·min−1·°C−3) and 93.64 (10-8%·min−1·°C−3), significantly higher than 30.90 (10-8 %·min−1·°C−3) of inertinite. The above results showed that vitrinite had more aliphatic long chains and alkyl side chain, tar-rich coal and vitrinite had better pyrolysis reaction performance and strong volatilization ability, inertinite had less hydrogen-rich structure, poor pyrolysis reaction performance and stronger stability. Based on the discussion of the relationship between functional groups distribution and reaction performance of tar-rich coal and macerals, variation range of structural parameters with functional groups distribution was obtained. [ABSTRACT FROM AUTHOR]

Hydrogen-rich syngas was a clean energy and an important industrial material. Based on the decoupling strategy of biomass chemical looping gasification process, this paper proposed a strategy of metal oxides embedded into molecular sieves to prepare highly dispersed and nanosized oxygen carriers for producing hydrogen-rich syngas. NiO@SBA-15, Fe 2 O 3 @SBA-15, and NiFe 2 O 4 @SBA-15 were prepared by the impregnation method, and the reaction conditions on the chemical looping reforming of toluene were investigated. The results showed that NiFe 2 O 4 @SBA-15 had the highest toluene conversion rate of 93.4% and a relatively high CO selectivity rate of 80.7%. It was confirmed that the embedding strategy can effectively enhance the nanocrystallization and dispersion of metal oxides in oxygen carriers, which could effectively reduce sintering. The inverse spinel structure of NiFe 2 O 4 made the oxygen carrier have more metal adsorption sites and a closer reaction distance, which were beneficial to the adsorption and reaction of the fuel. After testing, the optimum reaction temperature was 750 °C, and the optimum weight hourly space velocity was 1.168 h−1. In the 10 cycles of testing of 20 NiFe 2 O 4 @SBA-15, the average conversion rate of toluene was 95.34%, the moderate selectivity of CO in the gaseous product was 94.83%, the average H/C ratio was 1.97, which indicated that the cycle stability is good. It provided a reference for developing and designing future oxygen carriers of biomass chemical looping reforming. • A decoupling strategy for biomass chemical looping reforming was proposed. • Fe 2 O 3 @SBA-15, NiO@SBA-15, and NiFe 2 O 4 @SBA-15 were prepared by embedding strategy. • NiFe 2 O 4 @SBA-15 achieved toluene conversion of 95.34% and average H/C ratio of 1.97. • The possible reaction mechanism of oxygen carrier and toluene was revealed. [ABSTRACT FROM AUTHOR]

• The structure of small fractal cube medium is applied to large spherical particles. • A new pore-parameters statistics method for fractal particle is proposed. • Random pressure distribution inside fractal heterogeneous particle is obtained. • Internal pressure decreases the tar yield and increases the light tar ratio greatly. • The Pareto solution for the optimization of both tar yield and quality is obtained. Pulverized coal fast pyrolysis is a coal conversion technology with high tar yield but low tar quality. Because of the small particle size and high heating rate, significant pressure exists inside the particles, affecting the final product distribution. This study established a cube media according to fractal law and generated coal particles with the same pore structure to calculate the internal pressure distribution. The pressure profile was further coupled with a tar generation mechanism to investigate the pressure effect on tar product. The single Shenfu coal particle pyrolysis was simulated in a drop tube furnace reactor model. The results showed that the total tar yield decreased, and the light fraction increased with the correction of internal particle pressure. Maximum deviation reached 28.86% and 23.09%. A particle size of 25 μ m was beneficial to increase the tar yield, while carrier gas temperature of 973 K helped improve the tar quality. [ABSTRACT FROM AUTHOR]

• The embedding strategy for oxygen carriers proposed Fe 2 O 3 nano-sized and dispersed. • The embedding strategy improved the recycling and reforming performance of OCs. • The utilization efficiency of lattice oxygen was dincreased for embedding strategy. • The nanocrystallization of Fe 2 O 3 reduces the potential barrier to forming CO. Macromolecular volatiles are one of the important components of biomass pyrolysis products. Chemical looping reforming can efficiently convert macromolecular components into hydrogen-rich syngas. Oxygen carriers with good partial oxidation performance and excellent recycling performance are the key factor. In this work, the embeddedness strategy was proposed to regulate the micro-reaction environment of oxygen carriers and thus improve the recycling and partial oxidation performance. The characteristics of toluene chemical looping reforming via Fe 2 O 3 embedded in SBA-15 (Fe 2 O 3 @SBA-15) were studied in fixed-bed reactor. The performances of Fe 2 O 3 and Fe 2 O 3 @SBA-15 were compared. The effect of pure Fe 2 O 3 particle size, Fe 2 O 3 loading amount, and reaction temperature were investigated. Thermodynamic analysis results showed that the reaction could proceed spontaneously when the temperature was higher than 600℃. The experimental results showed that chemical looping reforming process could be divided into two stages, including partial oxidation and catalytic cracking. The main product in the first stage was syngas, while the main product in the latter stage was H 2 and coke. The Fe 2 O 3 particle size decreased from 5um to 30 nm, and the CO selectivity increased from 25.87% to 33.15%. This indicated that the nanocrystallization of Fe 2 O 3 would improve the partial oxidation performance. Compared with pure Fe 2 O 3 , the CO selectivity of Fe 2 O 3 @SBA-15 rose from 25.9% to 96.2%. The utilization rate of lattice oxygen and the conversion rate of toluene increased significantly. At 900℃, toluene was nearly completely converted, and the utilization rate of lattice oxygen reached 92.7%. The toluene conversion increased with the elevation of Fe 2 O 3 loading, and the CO selectivity always remained above 87.9%. With the elevation of reaction temperature from 700℃-900℃, toluene conversion increased from 30.5% to 95.6%, while CO selectivity decreased slightly. More importantly, the stability test results showed that after 10 cycles, toluene conversion rate only dropped by 1.9%, and the average concentration of gas products remained stable. The above results showed that the embeddedness of Fe 2 O 3 in SBA-15 could effectively improve CO selectivity, enhance the transmission and release of lattice oxygen, and elevate the catalytic performance and cycle stability of oxygen carriers. [ABSTRACT FROM AUTHOR]

The development of phase change materials with a high latent heat of fusion and thermal conductivity is a key issue that needs to be addressed in power batteries thermal management system. In this study, an imidazolium ionic liquid ([C 16 MIM]Br) suitable for latent heat storage was synthesized by quaternization reaction. The composite phase change material of ionic liquid/graphene/carbon nanotube aerogel was prepared by hydrothermal self-assembly and vacuum impregnation method utilizing the unique π-π interaction between the delocalized electron of the heterocyclic cation of the ionic liquid and the sp2 bonded carbon materials. The prepared ionic liquid-based phase change materials had high latent heat of phase change, excellent thermal stability, and enhanced thermal conductivity. The thermal conductivity of the composite material reached 0.751 W/(m·K) at a carbon nanotubes addition of 15 wt%, which was 232% higher than that of the pure ionic liquid (0.226 W/(m·K)). The enhancement was attributed to the three-dimensional network in the graphene/multi-walled carbon nanotubes aerogel which was beneficial to improve the dispersion of multi-walled carbon nanotubes in the matrix and promote the uniform penetration of the ionic liquid phase change material. As a result, the designed structure provided effective ways for phonon transmitting and improved the thermal conductivity of the composites. • Phase change temperature and enthalpy of fusion of ionic liquid were investigated. • Graphene aerogel promoted the dispersion of carbon nanotubes. • The interactions between the ionic liquid matrix and the additives were clarified. • The three-dimensional graphene structure improved the thermal conductivity. [ABSTRACT FROM AUTHOR]

This paper focuses on the development of chemical-looping reforming of macromolecular organic compounds from biomass pyrolysis based on decoupling strategy, including glycerol, benzene, and toluene. Firstly, the influence characteristics of pyrolysis conditions on the distribution of volatile are analyzed. Pyrolysis temperature and heating rate are the two most important factors. Three technical routes to prepare hydrogen-rich syngas by chemical-looping reforming of typical macromolecular components in the volatile components of biomass pyrolysis were emphatically discussed, which include auto-thermal chemical-looping reforming (CLRa), chemical-looping steam reforming (CLSR), and chemical-looping dry reforming (CLDR). The types of oxygen carriers, reforming characteristics, and reaction mechanisms related to the above three routes were compared. In the future, chemical-looping reforming based on the decoupling strategy focuses on developing oxygen carriers with high lattice oxygen reserves, fast transmission rate and good anti-coke formation performance, and more efficient fluidized bed reactors. At the same time, density functional theory calculations and reaction experiments combined to reveal the reaction mechanism, integrate and optimize the system's energy flow and material flow. [Display omitted] • Decoupling strategy divided chemical looping reforming into three approaches. • Three paths of macromolecular chemical looping reforming were analyzed. • Lattice oxygen transfer and reactivity of metal oxides were the keys to oxygen carrier. • There were mainly two surface reaction mechanisms between volatiles and oxygen carrier. • Key points of chemical looping reforming based on decoupling strategy were proposed. [ABSTRACT FROM AUTHOR]