Catalysts For Steam Reforming Research Articles

Novel highly dispersed Ni-based oxides catalysts for ethanol steam reforming

To prepare high-performance Ethanol Steam Reforming (ESR) catalyst, copper and magnesium were added into NiAl Layered Double Hydroxides (NiAl-LDHs) employing the coprecipitation method as the second and third metals for reducing the sintering of nickel active components and controlling the acid sites. Afterward, NiCuMgAl-LDHs were wrapped on the SiO2 nanospheres to form a spherical layered structure. The results showed that, compared with the NiAl catalyst, after adding Cu metal, resulting from the synergistic effect of Ni–Cu, the ethanol conversion rate increased at different temperature ranges, and ethanol could be wholly converted at 500 °C. With the addition of Mg for neutralize the acid sites of the catalyst, no ethylene, ethanol dehydration product, was produced over the entire reaction temperature range (350–600 °C). NiCuMgAl-LDHs grows vertically on the surface of SiO2 because its hierarchical layered structure is beneficial to inhibit the collapse of laminates, which makes the active components of Ni on SiO2@NiCuMgAl more dispersed and exists edge and corner sites with few coordinative unsaturated active sites, thus exposing of active components and then enhanced performance. Finally, through the catalyst composition and structure optimization, the ethanol was converted entirely, and the stable hydrogen production was realized in the 19 h test.

Acid activation of montmorillonite and its application for production of hydrogen via steam reforming of dimethyl ether

A series of acid-activated montmorillonites (Acid-MMTs) were prepared via Na-montmorillonite treated with nitric acid solution at different treatment temperature and time. And the Acid-MMTs used as solid acid were physically mixed with commercial Cu/ZnO/Al2O3 to obtain bifunctional catalysts for steam reforming of dimethyl ether (SRD) reaction. The results showed that the structure, texture and acidity of Acid-MMTs were significantly changed compared with Na-MMT, which was dependent on the acid treatment conditions. The structure and acidity of Acid-MMTs obviously affected the SRD performance over bifunctional catalyst. The bifunctional catalyst composed of the Na-MMT activated in 20% nitric acid solution at 80°C for 12 h (Acid-MMT-80/12) and Cu/ZnO/Al2O3 exhibited the best SRD performance, with the dimethyl ether conversion and H2 yield reaching 97% and 94% under the conditions of p=0.1 MPa, t=350°C, GHSV=3000 h−1, respectively, and DME conversion and H2 yield remained basically constant in 10 h, indicating that the catalyst had better stability.

Comparison of bimetallic Co-Ru nanoparticles supported on highly porous activated carbonized polyacrylonitrile with monometallic ones in ethanol steam reforming

A method for simultaneous formation of mono- (Co, Ru) or bimetallic (Co-Ru) nanoparticles and a highly porous carbon support is proposed. The obtained IR-PAN-Co, IR-PAN-Ru and IR-PAN-Co-Ru samples based on pyrolyzed polyacrylonitrile are characterized by a specific surface area within the range of 1683–2174 m2 g-1, which strongly depends on the nature of the metal used. It has been shown that the presence of cobalt leads to the graphitization of amorphous carbon and the formation of carbon shells around the mono- and bimetallic nanoparticles. The average size of metallic nanoparticles for all three samples ranged within 12–20 nm. The comparison of the samples revealed a dramatic advantage of the bimetallic catalyst in the ethanol steam reforming (ESR). The IR-PAN-Co-Ru sample has shown the highest hydrogen yield, which was 5.6 moles per mole of EtOH at 550 °C. To evaluate the stability of the catalysts, the catalytic test was carried out for 17 h after which no deactivation of the catalysts was observed. The spent catalysts were characterized by the same techniques as the as-prepared ones. It was found that there are no significant changes in the structure of the catalysts after the ESR reaction. The presence of filamentous carbon in the spent cobalt-based catalysts has been observed, which does not lead to deactivation in the time period studied.

Steam reforming of n-hexane and toluene: Understanding impacts of structural difference of aliphatic and aromatic hydrocarbons on their coking behaviours

Plastic wastes are potential feedstock for the production of hydrogen via gasification. Aliphatic hydrocarbons and aromatic hydrocarbons are important fractions from pyrolysis of plastic wastes, which might show the different reaction behaviors in steam reforming reactions due to their distinct molecular structures. To explore this, in this study, steam reforming of n-hexane and toluene, two model compounds representing respective aliphatic hydrocarbons and aromatic hydrocarbons, over Ni/SBA-15 catalyst were carried out. The in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) characterization of the steam reforming indicated that the dissociative absorption of n-hexane on nickel took place even at 100 °C, form abundant CHx species and consequently more CH4 in gaseous products. Nevertheless, the reaction intermediates from n-hexane could be gasified by the OH from adsorbed water rapidly. In comparison, the fragments from dissociative adsorption of toluene reacted with hydroxyl group of water, forming the stable intermediates bearing OH, CO, COC and CC functionalities, which were the precursors of coke and resulted in more serious coking. The coke from steam reforming of toluene showed a higher thermal stability, higher resistivity to oxidation as it was more aromatic and contained more defective with big fused ring structures. In addition, the majority carbon nanotubes generated during steam reforming of toluene had an inner diameter of 3–6 nm and outer diameter of 10–20 nm. Nickel species on tip of the nanotubes were wrapped with a carbon layer, which contributed to the deactivation of the catalyst in steam reforming of toluene.

Hydrogen generation by methanol steam reforming process by delafossite-type CuYO2 nanopowder catalyst

Due to global warming, the energy crisis, and climate change, hydrogen is to be used as an alternate renewable energy source. In industry, hydrogen generation is mainly obtained by the natural gas steam reforming reaction. In this study, delafossite CuYO 2 nanopowder was used as a catalyst for methanol steam reforming (MSR). The delafossite-structured CuYO 2 nanopowder was synthesized by the glycine nitrate process, annealed in N 2 , and used for MSR. The influences of different annealing temperatures on the phase transformation, surface area, and crystal structure composition of the Cu–Y–O powder were examined. The characteristics of the CuYO 2 nanopowder were identified by X-ray diffraction studies, Brunauer-Emmett-Teller studies (BET), field emission scanning electron microscopy studies, transmission electron microscopy, and X-ray photoelectron spectroscopy. The BET studies indicated that the surface area of the CuYO 2 nanopowder varied from 2 to 16 m 2 /g before and after annealing at different temperatures because of structural transformation. Scanning electron microscopy of the CuYO 2 nanopowder revealed a porous structure formed by the large amount of gas released during the glycine-nitrate process. Moreover, when the self-combusted nanopowder was annealed in N 2 at 750 °C, the porous structure of the CuYO 2 nanopowder was retained. The CuYO 2 catalyst in MSR performance was estimated, and the hydrogen generation rate reached as high as 1735.65 ml STP min −1 g-cat −1 at 300 °C without reduction treatment. Besides, the CuYO 2 catalyst exhibit a higher hydrogen production rate at a lower temperature. The hydrogen generation performance of this CuYO 2 catalyst could be of great importance in industry and have a global economic impact. Hydrogen generation over the delafossite-Type CuYO 2 nanopowder catalyst. • CuYO 2 catalyst was prepared by a self-combusted glycine nitrate process. • CuYO 2 catalyst was applied for the methanol steam reforming. • The surface area of CuYO 2 powder varied from 2.9 to 16 m 2 /g. • The CuYO 2 exhibited hydrogen production rate as 1735.65 ml/min g-cat at 300 °C. • The CuYO 2 exhibit the higher hydrogen production rate at lower temperature.

Promoting the Selectivity of Pt/m-ZrO2 Ethanol Steam Reforming Catalysts with K and Rb Dopants.

The ethanol steam reforming reaction (ESR) was investigated on unpromoted and potassium- and rubidium-promoted monoclinic zirconia-supported platinum (Pt/m-ZrO2) catalysts. Evidence from in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) characterization indicates that ethanol dissociates to ethoxy species, which undergo oxidative dehydrogenation to acetate followed by acetate decomposition. The acetate decomposition pathway depends on catalyst composition. The decarboxylation pathway tends to produce higher overall hydrogen selectivity and is the most favored route at high alkali loading (2.55 wt.% K and higher or 4.25 wt.% Rb and higher). On the other hand, decarbonylation is a significant route for the undoped catalyst or when a low alkali loading (e.g., 0.85% K or 0.93% Rb) is used, thus lowering the overall H2 selectivity of the process. Results of in situ DRIFTS and the temperature-programmed reaction of ESR show that alkali doping promotes forward acetate decomposition while exposed metallic sites tend to facilitate decarbonylation. In previous work, 1.8 wt.% Na was found to hinder decarbonylation completely. Due to the fact that 1.8 wt.% Na is atomically equivalent to 3.1 wt.% K and 6.7 wt.% Rb, the results show that less K (2.55% K) or Rb (4.25% Rb) is needed to suppress decarbonylation; that is, more basic cations are more efficient promoters for improving the overall hydrogen selectivity of the ESR process.

Ni/LaBO3 (B = Al, Cr, Fe) Catalysts for Steam Reforming of Methane (SRM): On the Interaction Between Ni and LaBO3 Perovskites with Differed Fine Structures

Ni/LaBO3 (B = Al, Cr, Fe) Catalysts for Steam Reforming of Methane (SRM): On the Interaction Between Ni and LaBO3 Perovskites with Differed Fine Structures

Hydrogen production by sewage sludge gasification in supercritical water with high heating rate batch reactor

Sewage sludge gasification in supercritical water was studied with high heating rate batch reactor. Effect of temperature, pressure, residence time and catalyst were investigated. The hydrogen yield, gasification efficiency, carbon gasification efficiency and hydrogen yield potential were mainly affected by temperature. The maximum values of them reached 20.66 mol/kg, 73.49%, 61.16% and 41.34% without catalyst at 750 °C and 30 min respectively. The modified detailed kinetics indicated steam reforming, water-gas shift and pyrolysis promoted the formation of H2 and CO2 when temperature was ranged from 550 to 750 °C at the initial residence time. As residence time increased, the water-gas shift was dominant. Meanwhile, the formation of CO and CH4 were inhibited when temperature and residence time increased. The addition of mixed catalysts promoted the three reactions and formation of hydrogen better at lower reaction condition. The mixed use of both catalysts could enhance the gasification and the formation of hydrogen better. The increased loading of RNi-Mo2 could enhance the formation of hydrogen better because the heterogeneous catalyst could promote steam reforming and alkali catalyst could promote water-gas shift reaction better.

Role of Fe Species of Ni-Based Catalysts for Efficient Low-Temperature Ethanol Steam Reforming.

The suppression of methane and coke formation over Ni-based catalysts for low temperature ethanol steam reforming remains challenging. This paper describes the structural evolution of Fe-modified Ni/MgAl2O4 catalysts and the influence of iron species on methane and coke suppression for low temperature ethanol steam reforming. Ni–Fe alloy catalysts are gradually oxidized by water to generate Ni-rich alloy and γ-Fe2O3 species at steam-to-carbon ratio of 4. The electron transfer from iron to nickel within Ni–Fe alloy weakens the CO adsorption and effectively alleviates the CO/CO2 methanation. The oxidation capacity of γ-Fe2O3 species promotes the transformation of ethoxy to acetate groups to avoid methane formation and the elimination of carbon deposits for anticoking. Ni10Fe10/MgAl2O4 shows a superior performance with a highest H2 yield of 4.6 mol/mol ethanol at 400 °C for 15 h. This research could potentially provide instructions for the design of Ni-based catalysts for low-temperature ethanol steam reforming.

Anti-coking freeze-dried NiMgAl catalysts for dry and steam reforming of methane

Finding supported nickel catalysts with high activity and stability is yet a challenging aim for industrial applications. In this work, we synthesized a surface defect-promoted Ni catalyst supported on Mg/Al hydrotalcite via a freeze-dried method instead of calcination. This approach leads to the increase in oxygen vacancies, which is attributed to the high dispersion of active sites after adding samarium. X-ray diffraction (XRD) measurements demonstrate a homogeneous layered double hydroxide (LDH) structure without the formation of any oxides. High-resolution transmission electron microscopy (HR-TEM) and field emission scanning electron microscopy images (FE-SEM) illustrated that the samarium-promoted NiMgAl catalyst possesses a scaffold structure with surface defects and oxygen vacancies compared to the unpromoted NiMgAl catalyst which confirmed by X-ray photoelectron spectroscopy (XPS). Moreover, the impact of the samarium incorporation on the physicochemical features of NiMgAl catalysts was investigated for catalytic activity in dry and steam reforming of methane at 700 °C. NiMgAl-Sm catalyst showed the highest conversion of CH4 (72%) and stability without any carbon formation during 20 h of time on stream in dry reforming process. because the strong metal–support interaction inhibits the sintering of nanocatalysts at 700 °C and the scaffold structure increases the mass transportation of feedstock and products.

Fast start-up structured CuFeMg/Al2O3 catalyst applied in microreactor for efficient hydrogen production in methanol steam reforming

The metal-oxide interaction has been proven to have extremely favorable effects on the improvement of adsorption strength tuning and catalytic performance. FeOx was found to reduce the reaction energy barrier of Cu-based catalyst in methanol steam reforming (MSR) by DFT calculation. Herein, a mesh-type CuFeMg/Al2O3 structural catalyst was synthesized and applied to MSR to explore the FeOx modification effect. In the microreactor, the catalyst showed 97.8% hydrogen yield and 2.5 times the hydrogen production efficiency of commercial catalysts. The in-situ start-up time of the catalyst without pre-reduction requires only 18 min, which is nearly 98% less time-saving compared to commercial catalysts. Meanwhile, the activity of the catalyst was basically stable in the 100-hour durability evaluation. The characterization analysis confirmed that FeOx not only enhanced the adsorption and activation capability of H2O but facilitated the rearrangement of electrons. CuFe electronic interaction had high-efficiency synergy in MSR.

Discovering indium as hydrogen production booster for a Cu/SiO2 catalyst in steam reforming of methanol

We report on the use of In as an effective H2 production promoter in a Cu/SiO2 catalyst for the steam reforming of methanol. To date, In promotion has been limited to noble metals because of its tendency to “bury” other metals thus compromising the catalytic activity. Here, we prepared a silica-supported Cu-In catalyst via a urea-assisted co-precipitation method that showed a higher H2 productivity compared to the monometallic catalyst and a remarkable H2/CO2 molar ratio of almost 3 at 220 °C. Through XPS, XRPD and HRTEM-EDX along with H2- and CO-TPR, H2O-TPD, and N2O titrations, supported by computational modeling, we attributed such superior performances to an easier H2O activation due to improved electronic properties of the Cu phase, that is, its lower oxidation state via electron density transfer from the InOx buffer phase as a 1D “necklace” structures crucially mediating the interaction of small Cu nanoparticles (2.6 nm) and silica.

H2S-resistant CeO2-NiO-MgO-Al2O3 LDH-derived catalysts for steam reforming of toluene

Recently, biomass gasification has garnered a lot of attention due to its potential to produce hydrogen-rich syngas. In this research paper, H2S resistant catalysts for steam reforming of toluene as a model tar compound is studied on CeO2-NiO-MgO-Al2O3 (Ce-NMA) hydrotalcite-derived catalysts synthesized by homogeneous urea hydrolysis. A family of Ce-NMA catalysts were synthesized with different Ce loading: 0Ce-NMA, 5Ce-NMA, 10Ce-NMA, 15Ce-NMA and 20Ce-NMA. Among all the catalysts, the performance of the catalysts improved up to 15Ce-NMA, which showed the most stable performance in the presence of H2S poison. The H2-TPR and XPS showed that the presence of ceria improved the reducibility of the catalysts by facilitating electron transfer to nickel. 15Ce-NMA gave a conversion of 82%, whereas 20Ce-NMA showed a 96% toluene conversion. However, the recovery of 15Ce-NMA was very quick (30-45min) as against that of 20Ce-NMA, which deactivated to 40% conversion and took 2 h to recover the performance. The XPS of reduced catalysts showed that Ni0/Ni2+ ratio constantly increased with increasing ceria loading due to the Ce3+/Ce4+ redox pairs, which aided the reduction of Ni2+ to Ni0. The TG/DTA analysis revealed that the highest amount of carbon was formed over 0Ce-NMA and 20Ce-NMA, meaning Ce loading was only effective till a certain amount. 15Ce-NMA demonstrated lower carbon deposition as compared to 0Ce-NMA and 20Ce-NMA. Raman analysis revealed that the type of carbon varied in the 20Ce-NMA. The graphitic carbon decreased till 15Ce-NMA but suddenly increased in 20Ce-NMA, leading to higher carbon deposition and lower activity in the catalyst.

Characteristics and activity of Ni/CeO<sub>2</sub> catalyst modified by Cr<sub>2</sub>O<sub>3</sub> in combined steam and CO2 reforming of CH4

A series of 10%wtNiO/CeO2-nanorod catalyst without and with Cr2O3 additive was prepared by simultaneous impregnation method. Several techniques, including N2 physisorption measurements, X-ray powder diffraction (XRD), temperature-programmed reduction using H2 (H2-TPR), CO2 temperature-programmed desorption (CO2-TPD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) were used to investigate catalysts’ physico-chemical properties. The activity of the catalysts in combined steam and CO2 reforming of CH4 (BRM) was investigated at temperature range of 550-800 °C. The results showed that 10%NiO0.1%Cr2O3/CeO2 catalyst had the best catalytic performance due to a better reducibility and basicity. At 700 °C and CH4:CO2:H2O molar ratio in feed stream of 3:1.2:2.4, both conversion of CH4 and CO2 on this catalyst reached 98.5%.

Arming wood carbon with carbon-coated mesoporous nickel-silica nanolayer as monolithic composite catalyst for steam reforming of toluene

Steam reforming is an effective measure for biomass tar elimination as well as H2-rich syngas (H2 + CO) production. However, the granular or powdery Ni-based catalysts are prone to deactivation, which is caused by inappropriate mass transfer and clogging of catalyst bed. Herein, monolithic wood carbon (WC) with low-tortuosity microchannels is armed with a carbon-coated mesoporous nickel-silica nanocomposite (Ni-SiO2@C) layer via an evaporation-induced self-assembly and calcination procedure for toluene (tar model compound) steam reforming. The quality of the Ni-SiO2@C layer growing on the surface of WC microchannel is affected by the molar ratios of Si/Ni feed. A uniform thin-layer coverage is obtained on the Ni-15SiO2@C/WC (Si/Ni = 15) catalyst, where highly dispersed Ni nanoparticles (average size of 6.6 nm) with appropriate metal-support interaction and remarkable mechanical strength are achieved. The mass transfer, coke resistance, and hydrothermal stability of the Ni-15SiO2@C/WC catalyst were significantly improved by the multilevel structure assembled from the WC microchannels and the secondary ordered SiO2 mesopores. A stable toluene conversion over 97% with an H2 yield of 135 μmol/min was obtained at 600 °C on the Ni-15SiO2@C/WC catalyst. This work opens a new window for facilely constructing high-performance wood carbon-based monolithic tar reforming catalyst.

Co-precipitation continuous synthesis of the Ni-Rh-Ce0.75Zr0.25O2-δ catalyst in the membrane dispersion microreactor system for n-dodecane steam reforming to hydrogen

Precipitation at the micro-scale to produce nanoparticles with small particle size and uniform dispersion is feasible. A membrane dispersion microreactor (MR) - matching spiral tube system was used to synthesize highly dispersed (MR)-Ni-Rh-Ce0.75Zr0.25O2-δ and (MR)-Ni- Ce0.75Zr0.25O2-δ catalysts with active metal particle sizes of 4.3 and 4.6 nm. Rapid nucleation of the catalyst precursor was achieved in the microreactor and ordered growth occurred in the spiral tube. Characterization by TEM, pulse CO chemisorption, and Raman spectroscopy prove that the catalysts synthesized in the microreactor system possess more oxygen vacancies and uniformly supported active metal than those in the stirred tank (S). The apparent activation energies of the catalysts for n-dodecane steam reforming (SR) increase in the following order: (MR)-Ni-Rh-CZO (62 kJ/mol) < (S)-Ni-Rh-CZO (67 kJ/mol) < (MR)-Ni- CZO (77 kJ/mol) < (S)-Ni-CZO (84 kJ/mol). The initial hydrogen yields of (MR)-Ni-Rh-CZO and (S)-Ni-Rh-CZO are 88 and 59%, respectively, at T = 650 °C, WHSV = 12 h−1, and S/C = 4. TPSR experiments indicated that (MR)-Ni-CZO mostly contributed to the cleavage of C–C and C–H bonds. The carbon deposition in the first 12 h of n-dodecane SR is only 2.4 mg/(g-cat·mol-H2). For optimizing the continuous synthesis method, the initial hydrogen yield can be further improved to above 95% by increasing the mixing intensity, decreasing the ratio of the dispersed to continuous phase, and increasing the spiral tube length to synthesize better-dispersed catalysts.

Thermochemical hydrogen production using Rh/CeO2/γ-Al2O3 catalyst by steam reforming of ethanol and water splitting in a packed bed reactor

This study is focused on investigating the dual performance of Rh/CeO2/γ-Al2O3 catalyst for steam reforming of ethanol (SRE) and thermochemical water splitting (TCWS) using a packed bed reactor. The catalyst is designed to be thermally stable containing an active phase of Rh and the redox component of CeO2 for oxygen exchange, supported on γ-Al2O3. The catalyst has been characterised by SEM, XRD, BET, TPR, TPD, XPS and TGA before testing in the reactor. The optimal temperature for SRE reaction over this catalyst is between 700 °C and 800 °C to produce high concentrations of hydrogen (~60%), and low CO and CH4. The selectivity towards CO and CH4 is higher at low temperatures and drops with rise in reaction temperature. Further, Rh/CeO2/γ-Al2O3 is found to be active for TCWS at relatively low temperatures (≤1200 °C). At temperatures as low as 800 °C, this catalyst is especially found suitable for multiple redox cycles, producing a total of 48.9 mmol/gcat in four redox cycles. The catalyst can be employed for large number of redox cycles when the reactor is operated at lower temperatures. Finally, the reaction pathways have been proposed for both SRE and TCWS on Rh/CeO2/γ-Al2O3 catalyst.

Nickel catalysts promoted with lanthanum for ethanol steam reforming: Influence of support and treatment on activity

The effect of support nature on the catalytic performance of Ni-based catalysts for ethanol steam reforming (ESR) was investigated. Nickel catalysts supported on lanthanum-modified Al2O3, TiO2, Al2O3-TiO2 and Al-pillared bentonite (denoted as Clay) were prepared by impregnation, characterized by X-ray diffraction (XRD), N2 adsoption-desorption, IR spectroscopy of acetonitrile adsorption and thermogravimetric analysis (TGA), and evaluated at 500 °C under atmospheric pressure. Both Ni/La-Al2O3 and Ni/La-TiO2-Al2O3 exhibited the best stability, whereas Ni/La-TiO2 and Ni/La-Clay deactivated quickly but with similar or higher H2 production. Catalyst deactivation was caused by carbon deposition, which formation was related to strong Brønsted sites. Efficiency of lanthanum as inhibitor of carbon deposition depended on the support nature.Oxidative regeneration allowed recovering initial activity of all used catalysts and even improving the performance of the latter two catalysts. This unexpected improvement can be due to change of nickel centres nature, caused by local overheating during the deposited carbon combustion.

Influence of the initial state of ZrO2 on genesis, activity and stability of Ni/ZrO2 catalysts for steam reforming of glycerol

The effect of the initial state of ZrO2 on properties of Ni/ZrO2 catalysts for hydrogen production in steam reforming of glycerol was investigated. The catalysts were synthesized by impregnating the supports obtained by varying the treatment temperature of ZrO2‧nH2O and introducing Y2O3 as a promoter. All materials were characterized by thermal analysis, X-ray diffraction, N2 physisorption, scanning electron microscopy, H2-TPR, NH3-TPD and transmission electron microscopy. The mutual influence of NiO and ZrO2 on the genesis of the phase composition, pore structure and reducibility was demonstrated. Different catalytic behavior is explained by influence of the initial form of the support on the size, morphology of Ni particles, and the support thermal stability. The initial activity of Ni/ZrO2is proportional to the monoclinic phase content. The catalysts based on tetragonal ZrO2 displayed the best stability. For the first time, the presence of the aldol condensation products in glycerol steam reforming was demonstrated.

Effect of boron doping on the performance of Ni/Biochar catalysts for steam reforming of toluene as a tar model compound

Biochar-supported nickel (Ni/BC) catalysts have potential applications in steam reforming of tar during biomass gasification. However, the industrial application of Ni/BC catalysts is restricted by their rapid deactivation caused by the gasification of biochar support and deposition of carbon on the active Ni metal. In this study, the effect of boron doping was explored on the performance of Ni/BC catalysts in steam reforming of toluene as a tar model compound. A series of Ni/BC and boron-doped Ni/BC catalysts were prepared by impregnating Ni salts on raw and acid-washed biomass as the starting materials and used in steam reforming of toluene as the tar model compound. It was found that boron doping significantly prolonged the lifetime of Ni/BC catalysts by interacting with Ni and the biochar support simultaneously. It is believed that boron doping lowered the gasification consumption rate of the biochar support in three ways: transforming the inherent K into more stable borates, inhibiting the desorption of CO and CO2, and forming B2O3 as the active site blocker. Furthermore, boron doping also reduced coke deposition on the Ni particles.