Coke Precursors Research Articles

Steam reforming of typical small organics derived from bio-oil: Correlation of their reaction behaviors with molecular structures

This study investigated the steam reforming of a series of organic molecules with varied molecular structures (methanol, formic acid, ethanol, acetic acid, acetaldehyde, acetone, furfural, guaiacol), aiming to understand the impacts of functionalities of these organics on their reaction behaviors. The results showed that molecular structures drastically influenced reactivity and tendencies towards coking during steam reforming. Methanol and formic acid could effectively be reformed and coking was insignificant, as no cracking of CC bonds involved in their conversion. Ethanol, acetic acid, acetaldehyde or acetone was more difficult to be reformed, and coking was significant, especially for acetone or acetaldehyde bearing the carbonyl functionality that could be retained in the precursors of coke. The substantial amount of coke formed in steam reforming of furfural and guaiacol originating from their π-conjugated ring structures and the coke was more graphite-like. In comparison, the coke from reforming of ethanol, acetic acid, acetaldehyde or acetone were more disordered. The in situ DRIFTS studies of steam reforming indicated that the CC and CH functionalities were generated even at 100 °C, which could contribute to coking, when they could not be effectively gasified via steam reforming.

Furfural hydrodeoxygenation on iron and platinum catalysts

Furfural can be converted into a wide range of high-octane products like 2-methylfuran (2-MF) through hydrodeoxygenation (HDO). Iron-based catalyst (Fe/SiO2), has shown high selectivity for gas phase conversion of furfural to 2-MF at atmospheric pressure and 573 K. However, it showed rapid deactivation. Furfural is the main coke precursor, although coke is also formed when 2-MF and furan are used as reactants, but in lower quantities. Coke profiles along the catalytic bed suggest that tetra-hydrofuran is an important coke precursor. The addition of a second metal like platinum, even in very low proportions, generates hydrogen spillover leading to an important improvement in the stability of the catalyst. The Fe/Pt ratio on the surface regulates the amount of coke deposited because it modifies the iron particle sizes, the interaction with the support and the amount of hydrogen available for the reactions. These phenomena influence the reaction, coke formation and regeneration mechanisms.

Hydrodeoxygenation of raw bio-oil towards platform chemicals over FeMoP/zeolite catalysts

The hydrodeoxygenation of raw bio-oil was investigated in a continuous fixed bed reactor over a series of FeMoP/zeolite catalysts, pursuing a maximized and stable production of phenolics and aromatics. After 5 h of reaction, the catalysts reach a pseudosteady activity state. The FeMoP/HZSM-5 catalyst yields the highest amount of carbon products (53.5 wt%) with the highest selectivity towards aromatics (13.6 wt%, dry basis) and phenolics (12.2 wt%), due to the synergy between the weak acidity of the FeMoP and the mild acidity of the HZSM-5 zeolite, which minimizes dehydration and gasification. The MFI framework allows the sweeping of coke precursors.

Ultrafine reverse micelle catalysts for slurry-phase residue hydrocracking

Ultrafine and stable slurry-phase hydrocracking catalysts were prepared by the reverse micelle (RM) method. The optimization of RM catalysts was carried out using different solvents, metal (molybdenum) concentrations, and reaction temperatures. The effect of cobalt as a promoter metal was also evaluated. For this preparation method, different solvents such as pentane, hexane, and diesel were used. Hydrocracking activities of the prepared catalysts were tested using vacuum residue (VR) that has a high concentration of impurities. The catalyst prepared by the RM method using diesel as the solvent shows very high hydrocracking activity of the vacuum residue. Coke formation at the end of the reaction by this catalyst is also very low compared with the other catalysts. The thermogravimetric analysis (TGA) results show that the catalyst prepared using diesel as solvent is thermally stable. With its high stability, the catalyst remains in an ultrafine dispersed phase at actual reaction conditions. These ultrafine catalyst particles form a layer in between the submicron mesophase, which is a precursor of coke. Therefore, coke formation is very low for this catalyst. Other two catalysts prepared using pentane and hexane solvents were found not to be stable at reaction conditions. In these, catalyst particles may agglomerate into big particles, which then act as nucleation sites for mesophase asphaltene, promoting coke formation instead of coke inhibition. The coke yield is also high at higher Mo concentrations in the catalyst. The results revealed that the RM method can be used effectively to prepare an ultrafine dispersed catalyst for residue hydrocracking. However, the use of a suitable solvent plays an important role in forming a stable dispersed and highly effective catalyst.

Ca–Al layered double hydroxides-derived Ni-based catalysts for hydrogen production via auto-thermal reforming of acetic acid

Biomass-derived acetic acid (HAc) is an alternative resource for hydrogen production, and heat self-sustained auto-thermal reforming (ATR) of HAc shows potential for practical application, while robust and stable catalysts remain as a key factor. Ca–Al layered double hydroxides (LDHs)-derived Ni-based catalysts were synthesized by co-precipitation, and tested in ATR of HAc for hydrogen production. Over the LDHs-derived Ca2.55Ni0.45AlO4.5 catalyst, active sites of Ni–CaO–Ca12Al14O33 were formed, and interaction among Ni, CaO and Ca12Al14O33 was proved to be a pivotal role for 1) thermal stability, 2) resistance to oxidation of Ni0 species, and 3) inhibiting coke deposition through catalytic cycle, CaO + CO2↔CaCO3 and CaCO3+*C↔CaO+2CO, for gasification of coking precursors. Hence, the Ca2.55Ni0.45AlO4.5 catalyst showed enhanced activity with no obvious deactivation in ATR: the acetic acid conversion rate was 100%, and the hydrogen yield remained stable near 2.75 mol-H2/mol-HAc at a rate of 40.34 mmol-H2/s/g-catalyst.

Unveiling coke formation mechanism in MFI zeolites during methanol-to-hydrocarbons conversion

Coke formation over MFI zeolites of different crystallite sizes was rigorously investigated in methanol-to-hydrocarbon conversion (MTH). The key experimental idea was based on the fact that soft coke in the zeolite micropores (internal coke) could be selectively removed by thermal treatment under H2, while heavy coke at the zeolite external surface (external coke) remained intact. This enabled us to analyze the amount, composition, chemical nature, and deactivating effects of internal and external cokes, separately. As the mass transfer of hydrocarbons was retarded with increasing zeolite crystallite size, an aromatic-based catalytic cycle became dominant in MTH compared to an olefin-based cycle. Consequently, methylated benzene intermediates were accumulated within the zeolite micropores. These methylated benzenes could also act as coke precursors and polymerize to form internal coke within the micropores. Aromatic products that diffused out of zeolite micropores could also be condensed at the external surface of the zeolite crystallites. Once the carbon deposits were formed at the external zeolite surface, the external coke continued to grow even non-catalytically by the thermal reaction with the methylated benzenes. Different zeolite catalysts and reaction times affected only the relative amounts of internal and external cokes, but not their respective chemical natures. The internal coke appeared to have the H/C ratio of 1.26 and a density of 1.0 g cm−3, while the external coke had much lower H/C ratio (0.28) and higher density (1.5 g cm−3). We propose that internal coke is likely to have the polymeric structures of the methylated acenes (i.e., linearly fused aromatic rings such as benzene, naphthalene, and anthracene) connected via methylene bridges. On the other hand, the external coke is highly polyaromatic with many fused rings. In terms of catalyst deactivation, the internal coke proved to be much more detrimental than the external coke.

Coke Yield Prediction Model for Pyrolysis and Oxidation Processes of Low-Asphaltene Heavy Oil

Accurate prediction of coke yield is the basis for simulation and operation of the in situ combustion process. In view of the low asphaltene content of heavy oil in China, this study established coke yield prediction models for the pyrolysis and oxidation processes of low-asphaltene heavy oil based on the coking characteristics of the main fractions, including saturates (S), aromatics (A), and resins (R). The models were verified by the experimental coke yields of heavy oils using a fixed-bed reaction system. The prediction model for the pyrolysis process included evaporation rate equations and kinetic equations for coking reactions. Besides the same parts with pyrolysis, the model for the oxidation process included the kinetic equation of coke oxidation. The evaporation rate equations were determined by fitting the mass loss rate in the evaporation range of thermogravimetric analysis (TGA) pyrolysis results with a maximum error of 6%. The kinetic parameters for the conversion of each fraction to the coke precursor were determined by the isoconversional method based on TGA results of the separated SAR fractions. Considering the interactions among fractions during oxidation, this study included mixtures of SAR fractions as the samples and obtained the mass loss results of a single SAR by subtraction. The activation energies of SAR pyrolysis range from 99 to 180 kJ/mol and those of SAR oxidation range from 92 to 130 kJ/mol. The kinetic parameters of coke from the coke precursor were obtained by temperature-programmed coking data of a prepared intermediate, with an activation energy of 177 kJ/mol in an inert atmosphere and 65 kJ/mol in an oxidizing atmosphere. The kinetic parameters of coke oxidation were derived by the isothermal kinetic method in TGA, with an activation energy of 136 kJ/mol. The experimental coke yields of Fengcheng and Hongqian heavy oils under various pyrolysis and oxidation conditions were predicted by this model with an error around 10%, indicating that this model could be successfully applied to the prediction of the coking process of low-asphaltene heavy oil under complex conditions.

Catalytic cracking of raw bio-oil under FCC unit conditions over different zeolite-based catalysts

The performance of different zeolite-based catalysts (HY, HZSM-5 and HBeta) on the catalytic cracking of bio-oil has been explored, using a simulated riser reactor and resembling industrial FCC conditions. The effect of the C/O (catalyst/bio-oil) ratio and the zeolite types have been assessed. The level of deoxygenation is >61% (increasing with C/O ratio). Total hydrocarbon yield was higher for the HBeta catalyst (56wt%), while the liquid hydrocarbons yields were relatively similar for all catalysts, obtaining higher gasoline yields with the HY catalyst (46–55wt%), and higher LPG yields with the HZSM-5 catalyst (12–14wt%) due to its higher acidity. The HY zeolite produced more coke (4–7wt%) given its capacity for retaining coke precursors within its micropores.

Engineering the Catalytic Properties of HZSM5 by Cobalt Modification and Post-synthetic Hierarchical Porosity Development

Hierarchical zeolites have been identified as special catalytic materials with improved catalytic properties. In this study, hierarchical bifunctional ZSM5 based catalysts were prepared by desilication for controlled mesoporosity development and have been modified by Co doping. Their performance in the catalytic pyrolysis of oak in a lab scale reactor was evaluated. Desilicated counterparts were proven more active in deoxygenation of bio oil, while carbon deposition on the catalysts reduced compared to non-desilicated counterparts. Increased Lewis acidity favors decarboxylation reactions, while higher olefins as well as PAH content indicate easier diffusion within and from the porous network and interactions in the mesopores. The conversion of bulky lignin molecules (alkoxy phenols) is enhanced by the mesopores, while acidity is of secondary importance. Coke deposition inside the pores is more profound in the desilicated catalysts due to larger pore size. Carbon deposition on the catalysts is reduced in the following order: HZSM5 > Co/HZSM5 > Ds-HZSM5 > Co/Ds-HZSM5. GC–MS characterization of the CH2Cl2 soluble coke indicated that for the desilicated counterparts the main coke precursors are the bulky lignin molecules which are partially deoxygenated.

Alternative diesel fuels with high hydrogen content in their molecular structures

Alternative fuel components have a continuously growing use worldwide. Hydrocarbons with high hydrogen to carbon ratio in their molecular structures are the most suitable alternative fuels. In this paper the special hydrocracking of waste fatty acids and waste lard to paraffin mixtures over sulfided NiMoP/Al2O3 is presented. The effect of feedstock additives was investigated on the catalyst performance, such as activity, selectivity, product yield and catalyst lifetime. It was concluded that coke precursors, which were formed from olefinic components reduced the catalyst performance. Olefins were generated as intermediates of hydrocracking but could be present also in the feedstocks. Based on the results it was also concluded that application of amine and phenol type additives in the feedstocks inhibited the formation of coke precursors and coke. Results of catalytic tests having length of ca. 1000 h were compared. Applying 200 mg/kg additive in favorable combination resulted in about 21–37 wt% increase in the yield of target products relative to that using feedstock without additives. The obtained target products were rich in n-paraffins and represented diesel blending components of >85 cetane number. Various ideas are proposed for the utilization of the obtained bio-paraffin mixture.

Insights into the size and structural effects of zeolitic supports on gaseous toluene oxidation over MnOx/HZSM-5 catalysts

HZSM-5 zeolites with micro/nano crystallites and hollow structure were respectively synthesized for the preparation of supported MnOx catalysts, and the size and structural effects of zeolitic supports on both the physicochemical properties and toluene oxidation performances of MnOx/HZSM-5 catalysts were extensively investigated by numerous characterizations and experimental evaluation. Beneficially from the higher surface area and hierarchical porosity of nanoscale hollow HZSM-5 (namely as H-Z5) zeolite, good surface dispersion of MnOx nanoparticles was acquired over the resultant supported MnOx catalyst (namely as MnOx/H-Z5), simultaneously achieving great enhancement of its low-temperature reducibility, surface oxygen mobility and more plentiful surface Mn4+ cations. The superiority in these physicochemical characteristics was reasonably correlated with the optimum catalytic activity and good catalytic durability for toluene oxidation over MnOx/H-Z5. The results of coke analysis indicated that MnOx/H-Z5 exhibited relatively higher coke-resistant ability since the highly dispersed MnOx nanoparticles on zeolite surface effectively promoted the oxidative destruction of toluene and other organics species. A possible reaction mechanism was proposed based on the in situ DRIFTS results, where the key reaction intermediates including benzaldehyde, benzoic acid and cyclic anhydride and the relevant conversion pathways were determined. The surface active oxygen originating from gas-phase oxygen activation by MnOx nanoparticles played a crucial role in the oxidative elimination of coke precursors into carbon dioxide and water under air atmosphere.

Electro-catalytic steam reforming of methane over Ni-CeO2/γ-Al2O3-MgO catalyst

Catalytic steam reforming of methane with Ni-based catalysts is essential for industrial hydrogen production, but the high reforming temperature results in the catalyst deactivation by severe carbon deposition. In this work, a novel electro-catalytic protocol for steam reforming of methane was developed with aims of lowering the reforming temperature and prolonging the catalyst life. Three Ni-based catalysts, i.e., Ni/γ-Al2O3 (Ni/Al2O3), Ni/γ-Al2O3-MgO (Ni/AM) and Ni-CeO2/γ-Al2O3-MgO (Ni-CeO2/AM) were prepared for electro-catalysis to investigate the effects of current intensity, reforming temperature, and steam to carbon ratio on methane conversion, H2 yield and CO selectivity. Moreover, stability tests were performed on the three catalysts. The results indicated that the presence of electric current promoted the methane steam reforming at relatively low temperatures. Among the three catalysts, Ni-CeO2/AM showed the best performance on catalytic efficiency. Under conditions of 600 °C and current of 4.5A, CH4 conversion, H2 yield and CO selectivity achieved 96.4%, 75.3% and 40.1% respectively over Ni-CeO2/AM, which were comparable with those from conventional process at 700 °C. Moreover, after a 9-hour stability test, the CH4 conversion was maintained over 95% under Ni-CeO2/AM. Characterization results of the catalysts from the stability texts showed that the current could help generate more active centers for CH4 activation while inhibit the conversion of coke precursors into carbon on the catalyst surface.

Hydrogen production from ethanol steam reforming: Effect of Ce content on catalytic performance of Co/Sepiolite catalyst

A series of Co-xCe/Sepiolite (SEP) catalysts were synthesized and evaluated in ethanol steam reforming (ESR) for hydrogen production. The properties of calcined and reduced catalysts were characterized by N2 adsorption-desorption, XRD, H2-TPR, XPS and HRTEM. These results indicated that Co metal dispersion and reducibility of Co-xCe/SEP catalysts were improved by Ce addition. In addition, the interaction between active metal phase and SEP support was significantly improved by Ce promoter, which could suppress the sinter and re-oxidation of Co metal phase during the catalytic test. Meanwhile, HRTEM and XPS analysis demonstrated a portion of cobalt ions incorporated into CeO2 lattice, enhanced the formation of oxygen vacancies, which could react with coke precursors on catalyst surface to remove carbon deposition. During the 4 h of ESR reaction under S/C = 3, T = 600 °C and WHSV = 21.5 h−1, Co-0.3Ce/SEP (Ce/Co mole ratio = 0.3) showed the highest carbon conversion rate of 90.8% and H2 yield of 69.1%. Combining the characterizations for spent catalysts, it was found that the unique catalytic performance of Co-0.3Ce/SEP was attributed to strong synergy effect among Co metal active sites, excellent thermostability of SEP and the formation of oxygen vacancies in CeO2. Additionally, Co-0.3Ce/SEP showed the exciting stability during 100 h on stream.

Zr-enhanced stability of ceria based supports for methane steam reforming at severe reaction conditions

Ceria based supports are an interesting choice for methane steam reforming due to their coke precursor's gasification activity and ability to stabilize nickel particles. However, sintering and coking studies with this type of catalysts is lacking, particularly at low temperature (600 °C) and low water/methane feed ratio (R ≤ 2). In this work, nickel catalysts supported on an optimized Zr-doped ceria were tested for methane steam reforming at various water/methane feed ratios and contact times. Zr addition improved both sintering and coking resistance; as studied separately by means of XRD and CH4-TPSR followed by O2-TPO and self-decoking experiments. Carbon deposition/gasification mechanisms on ceria based supports were discussed. Optimized NiCeZr formulation was proven to be a highly stable catalyst for methane steam reforming at the conditions mentioned above.

EPR Spectroscopic and Thermal Analysis Study of Spent NiMo/WO3–Al2O3 Catalysts for Hydrodeoxygenation of Vegetable Oil

This paper presents the results of an electron paramagnetic resonance (EPR) and thermal analysis (TGA, DTA) study of a series of bifunctional NiMo/WO3–Al2O3 catalysts containing 0 to 30 wt % WO3 modifier before and after testing them in the process of hydrodeoxygenation of vegetable oil. The dependence of the content of carbonaceous deposits in the spent samples (according to EPR and TGA) on the concentration of acid sites as determined by EPR of perylene probe molecules in the initial catalysts is determined. Deactivation is explained by the participation of medium- and weak-strength Bronsted acid sites in the condensation of the initial unsaturated hydrocarbon molecules and their intermediates leading to the formation of various forms of coke precursors.

Ordered Mesoporous Co3O4−Al2O3Binary Metal Oxides for CO Hydrogenation to Hydrocarbons: Synergy Effects of Phosphorus Modifier for an Enhanced Catalytic Activity and Stability

AbstractThe synergy effects of phosphorus modifier on highly ordered mesoporous binary metal oxides of Co3O4−Al2O3(m‐CoAl), prepared by nanocasting method using a hard template of KIT‐6, were observed by an enhanced catalytic and structural stability of the m‐CoAl during CO hydrogenation to hydrocarbons. The enhanced structural stability of the ordered mesoporous structures on the phosphorous‐modified m‐CoAl at an optimal amount of phosphorous modifier below 0.3 wt%P (P(3)/m‐CoAl) was attributed to the partial formation of thermally stable metal phosphates under a reductive Fischer‐Tropsch synthesis (FTS) reaction condition. The positive effects of the phosphorous modifier were originated from the partially formed SiO2‐like AlPO4phases on the outer surfaces of the m‐CoAl, as well as from partially formed irreducible and thermally stable spinel‐type cobalt aluminates (CoAl2O4). The hydrophobic SiO2‐like tridymite AlPO4surfaces on the ordered matrices of the P/m‐CoAl also effectively prevented the heavy wax (or coke precursors) depositions. The structural instability of the P/m‐CoAl was observed at a higher phosphorous content above 0.5wt%P by preferentially forming the largely segregated mixed metal oxides such as Co3O4−CoAl2O4−Co3(PO4)2through the phase transformations of the surface excess AlPO4.

Highly stable seed-derived ferrierite for carbonylation of dimethyl ether to methyl acetate: Effects of seed content to catalytic stability

Abstract The seed-derived ferrierite zeolite (FER) synthesized at different contents of FER seed component without using any organic structure-directing agent (OSDA) showed a higher catalytic activity and stability for a gas-phase carbonylation of dimethyl ether (DME) to methyl acetate (MA) at an optimal amount of the previously synthesized FER-seed with 15wt%. The optimal amount of FER-seed material played an important role to optimize the numbers of active Bronsted acid sites in 8-membered ring (8-MR) channels with less formation of coke precursors by decreasing defect sites through their recrystallization during the preparation step. The defected Lewis acidic extra-framework aluminum (EFAL) sites on the seed-derived FER surfaces were responsible for preferential coke depositions and for a retarded CO insertion by decreasing the rate of the gas-phase DME carbonylation reaction.

Deactivation of a hydrotreating catalyst during hydroprocessing of synthetic crude by metal bearing compounds

The objective of this study is to investigate the deactivation of CoMo/γ-Al2O3 catalyst by the metals present in the heavy oils. For this, a synthetic feed is prepared in which coke precursors are minimized. Therefore, dewaxing of a heavy crude is performed which contains very less amount of microcarbon residue (MCR) and asphaltene. A spent catalyst was generated from the hydrotreating of dewaxed oil in a microflow continuous reactor (MFU). The activities of spent (from MFU unit) and regenerated catalysts were compared with the fresh catalyst using the same dewaxed oil in a batch reactor. Detailed characterisations of fresh, spent, and regenerated catalysts were performed using thermogravimetric analysis (TGA), N2-sorption isotherms, Raman spectroscopy, scanning electron microscopy (SEM), and high resolution-transmission electron microscopy (HR-TEM). Hydrocracking and hydrotreating activities of the catalysts were evaluated with contact time. It has been found that the hydrodesulfurization (HDS) activity of the regenerated catalyst was even lower than that of spent catalyst. This confirmed that the deactivation occurs by metals from the feed. HR-TEM results indicates that low HDS activity of the regenerated catalyst was observed may be due to the phase change from type II to type I Co-Mo-S during the high-temperature regeneration process. Also, the HDS activity of the spent catalysts showed that Ni deposited from the feed perform the autocatalysis function. The higher hydrocracking activity of the regenerated catalyst suggests that bare alumina-support takes part in the cracking activity, particularly at a higher reaction temperature. The amount of MCR and n-heptane analyzed during the reaction at different contact times concluded that sediments are formed during the early stage of the reaction. As the reaction precedes these sediments agglomerated and separated out from the liquid hydrocarbons.

A comparison of Al2O3 and SiO2 supported Ni-based catalysts in their performance for the dry reforming of methane

Dry reforming of methane (DRM) with CO2 is of great significance in the environmental protection and the utilization of natural gas. SiO2 and Al2O3 are two typical catalyst supports used in DRM. To elucidate the effect of these two supports on the catalytic performance, in this work, Ni/SiO2 and Ni/Al2O3 catalysts are prepared by the incipient wetness method and characterized by BET, TEM, H2-TPR, XRD, TG and Raman technologies. The results indicate that the performance of Ni-based catalyst is closely related to the properties of support and the Ni/SiO2 and Ni/Al2O3 catalysts are rather different in their DRM performance. Ni/SiO2 catalyst exhibits higher initial activity but poor stability; its catalytic activity decreases rapidly in 15 h for DRM at 800°C. Because of the weak metal-support interaction, Ni species on the Ni/SiO2 catalyst is present as large Ni particles, which may promote the formation of coke precursors, viz., the multi-carbon Cn species, leading to the fast carbonaceous deposition and catalyst deactivation. In contrast, the Ni/Al2O3 catalyst displays a lower activity but a much higher stability; its activity in DRM keeps stable in 50 h. Although Ni particles in the Ni/Al2O3 catalyst is much smaller, the strong metal-support interaction promotes the formation of NiAlxOy species during the catalyst preparation process, which may lead to a decrease in the content of active Ni species and give the Ni/Al2O3 catalyst a relatively low catalytic activity in DRM; however, the strong metal-support interaction between Ni and Al2O3 is also of benefit to the formation and stabilization of small Ni particles, which can alleviate the carbanceous deposition and afford the Ni/Al2O3 catalyst a better stability.

Steam reforming of aromatic hydrocarbon at low temperature in electric field

Toluene steam reforming was conducted over Ni-supported La0.7Sr0.3AlO3-δ (LSAO) perovskite oxide at 473 K in an electric field, and high toluene conversion was achieved even at such low temperature. Steam reforming is generally done at higher temperatures because of the endothermic nature of this reaction and coke prevention, which requires the contribution of heat energy in great amounts. Reportedly, water activation is particularly difficult to achieve at lower temperatures. Results of kinetic analyses such as Arrhenius plots and partial pressure dependence have revealed that imposing an electric field promotes water activation over Ni/LSAO catalyst. According to steady state isotopic kinetic analysis (SSITKA) and temperature programmed desorption infrared (TPD-IR) measurements, such water activation was accelerated via a redox mechanism using surface lattice oxygen of LSAO. The stimulated mobile lattice oxygen oxidized the adsorbed toluene and formed coke precursor in the electric field. The electric field achieved a lowered reaction temperature for efficient hydrogen production and coke suppression with redox property of LSAO support during toluene steam reforming.