Diesel steam reforming with a nickel-alumina spinel catalyst for solid oxide fuel cell application

Liquid hydrocarbons (LC) are considered as fuel cells feed and, more particularly, as solid oxide fuel cell feed. Cost-effective LC-reforming catalysts are critically needed for the successful commercialization of such technologies. An alternative to noble metal catalysts, proposed by the authors in a previous publication, has been proven efficient for diesel steam reforming (SR). Nickel, less expensive and more readily available than noble metals, was used in a form that prevents deactivation. The catalyst formulation is a Ni-alumina spinel (NiAl₂O₄) supported on alumina (Al₂O₃) and yttria-stabilized zirconia (YSZ).SR of commercial diesel was undertaken for more than 15 h at high gas hourly space velocities and steam-to-carbon ratios lower than 2. Constant diesel conversion and high hydrogen concentrations were obtained. Ni catalyst characterization revealed no detectable amounts of carbon on the spinel catalyst surface Ni. The effect of catalyst composition (Ni concentration and YSZ presence) was studied to understand and optimize the developed catalyst. Two phenomena were found to be influenced by relative catalyst composition: water-gas-shift vs reforming reaction extent, and concentration of light hydrocarbons in products.     

Performance comparison of autothermal reforming for liquid hydrocarbons,gasoline and diesel for fuel cell applications

This paper discusses the reforming of liquid hydrocarbons to produce hydrogen for fuel cell applications, focusing on gasoline and diesel due to their high hydrogen density and well-established infrastructures. Gasoline and diesel are composed of numerous hydrocarbon species including paraffins, olefins, cycloparaffins, and aromatics. We have investigated the reforming characteristics of several representative liquid hydrocarbons. In the case of paraffin reforming, H₂ yield and reforming efficiency were close to thermodynamic equilibrium status (TES), although heavier hydrocarbons required slightly higher temperatures than lighter hydrocarbons. However, the conversion efficiency was much lower for aromatics than paraffins with similar carbon number. We have also investigated the reforming performance of simulated commercial diesel and gasoline using simple synthetic diesel and gasoline compositions. Reforming performances of our formulations were in good agreement with those of commercial fuels. In addition, the reforming of gas to liquid (GTL) resulted in high H₂ yield and reforming efficiency showing promise for possible fuel cell applications.     

Self-sustained operation of a kWe-class kerosene-reforming processor for solid oxide fuel cells

In this paper, fuel-processing technologies are developed for application in residential power generation (RPG) in solid oxide fuel cells (SOFCs). Kerosene is selected as the fuel because of its high hydrogen density and because of the established infrastructure that already exists in South Korea. A kerosene fuel processor with two different reaction stages, autothermal reforming (ATR) and adsorptive desulfurization reactions, is developed for SOFC operations. ATR is suited to the reforming of liquid hydrocarbon fuels because oxygen-aided reactions can break the aromatics in the fuel and steam can suppress carbon deposition during the reforming reaction. ATR can also be implemented as a self-sustaining reactor due to the exothermicity of the reaction. The kW_e self-sustained kerosene fuel processor, including the desulfurizer, operates for about 250 h in this study. This fuel processor does not require a heat exchanger between the ATR reactor and the desulfurizer or electric equipment for heat supply and fuel or water vaporization because a suitable temperature of the ATR reformate is reached for H₂S adsorption on the ZnO catalyst beds in desulfurizer. Although the CH₄ concentration in the reformate gas of the fuel processor is higher due to the lower temperature of ATR tail gas, SOFCs can directly use CH₄ as a fuel with the addition of sufficient steam feeds (H₂O/CH₄ ≥ 1.5), in contrast to low-temperature fuel cells. The reforming efficiency of the fuel processor is about 60%, and the desulfurizer removed H₂S to a sufficient level to allow for the operation of SOFCs.     

Long-term stability at fuel processing of diesel and kerosene

The long-term stability at autothermal reforming of diesel fuel and kerosene was studied using Juelich's autothermal reformer ATR 9.2, which is equipped with a commercial proprietary RhPt/Al₂O₃–CeO₂ catalyst. The experiment was run for 10,000 h of time on stream at constant reaction conditions with an O₂/C molar ratio of 0.47, a H₂O/C molar ratio of 1.9, and a gas hourly space velocity of 30,000 h⁻¹. Kerosene produced via the gas-to-liquid process and diesel fuel synthesized via the bio-to-liquid route were used. Both fuels were almost free of mass fractions of sulfur and aromatics. The trends for the desired main products of autothermal reforming H₂, CO, CO₂, and CH₄ were almost stable when kerosene was used. When the fuel mass flow was switched to diesel fuel however, different modes of catalyst deactivation occurred (active sites blocked by carbonaceous deposits, sintering processes), leading to a decrease in the concentrations of H₂ and CO₂ with a simultaneous increase in the CO content. This paper defines carbon conversion as the decisive criterion for evaluating the long-term stability during autothermal reforming of kerosene and diesel fuel. Carbon conversion was diminished via three different pathways during the long-term experiment. Undesired byproducts found in the gas phase leaving the reactor had the strongest impact on carbon conversion. These byproducts included ethene, propene, and benzene. Furthermore, a liquid oily residue was detected floating on the condensed unconverted mass flow of water. This happened once during the whole experiment. Finally, undesired organic byproducts were dissolved in the mass flow of unconverted water. These were found to be straight-chain and branched paraffins, esters, alcohols, acids, aldehydes, ketones, etc. Nevertheless, at the end of the long-term experiment, carbon conversion still amounted to more than 98.2%.     

Suppression of ethylene-induced carbon deposition in diesel autothermal reforming

Diesel has high-hydrogen density and well-developed infrastructure, which are beneficial properties for fuel cell commercialization. However, diesel reforming poses several technical difficulties, including carbon deposition, sulfur poisoning, and fuel delivery. Specifically, carbon deposition can cause catastrophic failures in diesel reformers. In diesel reformate gas, the concentration of ethylene, a carbon precursor, is higher than other shorter hydrocarbons (C₂–C₄). In this study, we examine the cause of ethylene formation in diesel reforming. Ethylene formation can be closely related to paraffins' decomposition from homogeneous reaction. A portion of the catalyst active sites can become occupied with aromatic compounds, degrading the activity of the catalyst. Thus, a portion of the paraffins is decomposed via non-catalytic, homogeneous reactions, accounting for much of the observed ethylene formation. In this study, reforming conditions and fuel delivery method are investigated with respect to ethylene formation. By using a diesel ultrasonic injector, reactant mixing was enhanced, resulting in suppression of ethylene formation. This subsequently inhibited the ethylene-induced carbon deposition and improved the long-term performance of diesel ATR (autothermal reforming).     

Thermodynamic analysis of solid oxide fuel cells operated with methanol and ethanol under direct utilization,steam reforming,dry reforming or partial oxidation conditions

There is increasing interest in developing solid oxide fuel cells (SOFC) for portable applications. For these devices it would be convenient to directly use a liquid fuel such as methanol and ethanol rather than hydrogen. The direct utilization of alcohol fuels in SOFC involves several processes, including the deposition of carbon, which can lead to irreversible deactivation of the fuel cell. Several publications have addressed the thermodynamic analysis of the reforming of methanol (MeOH) and ethanol (EtOH) in SOFC, but none have considered the direct utilization of these fuels. The equilibrium compositions, the carbon deposition boundaries, and the electromotive forces for the direct utilization and partial oxidation of methanol and ethanol in SOFC as a function of the fuel utilization are obtained in this study. In addition, the minimum amounts of H₂O, and CO₂ for direct and indirect reforming with MeOH and EtOH to avoid carbon formation are calculated.     

Hydrogen production by reforming of liquid hydrocarbons in a membrane reactor for portable power generation—Experimental studies

One of the most promising technologies for lightweight, compact, portable power generation is proton exchange membrane (PEM) fuel cells. PEM fuel cells, however, require a source of pure hydrogen. Steam reforming of hydrocarbons in an integrated membrane reactor has potential to provide pure hydrogen in a compact system. Continuous separation of product hydrogen from the reforming gas mixture is expected to increase the yield of hydrogen significantly as predicted by model simulations. In the laboratory-scale experimental studies reported here steam reforming of liquid hydrocarbon fuels, butane, methanol and Clearlite^® was conducted to produce pure hydrogen in a single step membrane reformer using commercially available Pd–Ag foil membranes and reforming/WGS catalysts. All of the experimental results demonstrated increase in hydrocarbon conversion due to hydrogen separation when compared with the hydrocarbon conversion without any hydrogen separation. Increase in hydrogen recovery was also shown to result in corresponding increase in hydrocarbon conversion in these studies demonstrating the basic concept. The experiments also provided insight into the effect of individual variables such as pressure, temperature, gas space velocity, and steam to carbon ratio. Steam reforming of butane was found to be limited by reaction kinetics for the experimental conditions used: catalysts used, average gas space velocity, and the reactor characteristics of surface area to volume ratio. Steam reforming of methanol in the presence of only WGS catalyst on the other hand indicated that the membrane reactor performance was limited by membrane permeation, especially at lower temperatures and lower feed pressures due to slower reconstitution of CO and H₂ into methane thus maintaining high hydrogen partial pressures in the reacting gas mixture. The limited amount of data collected with steam reforming of Clearlite^® indicated very good match between theoretical predictions and experimental results indicating that the underlying assumption of the simple model of conversion of hydrocarbons to CO and H₂ followed by equilibrium reconstitution to methane appears to be reasonable one.     

Life cycle cost analysis to examine the economical feasibility of hydrogen as an alternative fuel

This study uses a life cycle costing (LCC) methodology to identify when hydrogen can become economically feasible compared to the conventional fuels and which energy policy is the most effective at fostering the penetration of hydrogen in the competitive fuel market. The target hydrogen pathways in this study are H₂ via natural gas steam reforming (NG SR), H₂ via naphtha steam reforming (Naphtha SR), H₂ via liquefied petroleum gas steam reforming (LPG SR), and H₂ via water electrolysis (WE). In addition, the conventional fuels (gasoline, diesel) are also included for the comparison with the H₂ pathways.     

Steam reforming of methane over unsupported nickel catalysts

This paper describes a study of steam reforming of methane using unsupported nickel powder catalysts. The reaction yields were measured and the unsupported nickel powder surface was studied to explore its potential as a catalyst in internal or external reforming solid oxide fuel cells. The unsupported nickel catalyst used and presented in this paper is a pure micrometric nickel powder with an open filamentary structure, irregular ‘fractal-like’ surface and high external/internal surface ratio. CH₄ conversion increases and coke deposition decreases significantly with the decrease of CH₄:H₂O ratio. At a CH₄:H₂O ratio of 1:2 thermodynamic equilibrium is achieved, even with methane residence times of only ∼0.5 s. The CH₄ conversion is 98 ± 2% at 700 °C and no coke is generated during steam reforming which compares favorably with supported Ni catalyst systems. This ratio was used in further investigations to measure the hydrogen production, the CH₄ conversion, the H₂ yield and the selectivity of the CO, and CO₂ formation. Methane-rich fuel ratios cause significant deviations of the experimental results from the theoretical model, which has been partially correlated to the adsorption of carbon on the surface according to TEM, XPS and elemental analysis. At the fuel: water ratio of 1:2, the unsupported Ni catalyst exhibited high catalytic activity and stability during the steam reforming of methane at low-medium temperature range.     

High yield hydrogen production from low CO selectivity ethanol steam reforming over modified Ni/Y2O3 catalysts at low temperature for fuel cell application

Ethanol–water mixtures were converted directly into H₂ with 67.6% yield and >98% conversion by catalytic steam reforming at 350 °C over modified Ni/Y₂O₃ catalysts heat treated at 500 °C. XRD was used to test the structure and calculate the grain sizes of the samples with different scan rates. The initial reaction kinetics of ethanol over modified and unmodified Ni/Y₂O₃ catalysts were studied by steady state reaction and a first-order reaction with respect to ethanol was found. TPD was used to analyze mechanism of ethanol desorption over Ni/Y₂O₃ catalyst. Rapid vaporization, efficiency tube reactor and catalyst were used so that homogeneous reactions producing carbon, acetaldehyde, and carbon monoxide could be minimized. And even no CO detective measured during the first 49 h reforming test on the modified catalyst Ni/Y₂O₃. This process has great potential for low cost H₂ generation in fuel cells for small portable applications where liquid fuel storage is essential and where systems must be small, simple, and robust.     

The influence of aromatic compounds on the Rh-containing structured catalyst performance in steam and autothermal reforming of diesel fuel

The detailed experimental studies of the autothermal and steam reforming of model mixtures simulating the composition of commercial diesel fuel were carried out over Rh/Ce_0.75Zr_0.25O_2-δ-?-Al₂O₃/FeCrAl wire mesh honeycomb catalytic modules. The components of the diesel surrogates were n-hexadecane, o-xylene, and naphthalene as model compounds of aliphatics, mono-aromatics and diaromatics, respectively. It was shown that low reaction rate of diaromatics steam reforming facilitated increasing concentration of C₁–C₅ hydrocarbon by-products (primarily ethylene) in the gas phase, as well as formation of polyaromatic compounds by concurrent condensation reaction. These undesirable processes were responsible for increasing catalyst coking. Monoaromatic constituents hadn't any significant effect on the progress of undesirable side-reactions during autothermal and steam reforming of diesel surrogates.     

Experimental evaluation of methanol steam reforming reactor heated by catalyst combustion for kW-class SOFC

The distributed power generation of methanol steam reforming reactor combined with solid oxide fuel cell (SOFC) has the characteristics of outstanding economic advantages. In this paper, a methanol steam reforming reactor was designed which integrates catalyst combustion, vaporization and reforming. By catalyst combustion, it can achieve stable operation to supply fuel for kW-class SOFC in real time without additional heating equipment. The optimal operating condition of the reforming reactor is 523–553 K, and the steam to carbon ratio (S/C) is 1.2. To study the reforming performance, methanol steam reforming (MSR), methanol decomposition (MD), water-gas shift (WGS) were considered. Operating temperature is the greatest factor affecting reforming performance. The higher the reaction temperature, the lower the H₂ and CO₂, the higher the CO and the methanol conversion rate. The methanol conversion rate is up to 95.03%. The higher the liquid space velocity (LHSV), the lower the methanol conversion rate, the lowest is 90.7%. The temperature changes of the reforming reactor caused by the load change of stack takes about 30 min to reach new balance. Local hotspots within the reforming reactor lead to an excessive local temperature to test a small amount of CH₄ in the reforming gas. The methanation reaction cannot be ignored at the operating temperature. The reforming gas contains 70–75% H₂, 3–8% CO, 18–22% CO₂ and 0.0004–0.3% CH₄. Trace amounts of C₂H₆ and C₂H₄ are also found in some experiments. The reforming reactor can stably supply the fuel for up to 1125 W SOFC.     

Biomass pyrolysis oils for hydrogen production using chemical looping reforming

This study considers the feasibility of using highly oxygenated and volatile pyrolysis oils from biomass wastes as sustainable liquid fuels for conversion to a hydrogen-rich syngas using the chemical looping reforming process in a packed bed. Pine oil and palm empty fruit bunches oil- ‘EFB’- were investigated with a Ni/Al₂O₃ catalyst doubling as oxygen transfer material (OTM). The effect of molar steam to carbon ratio (S/C) and weight hourly space velocity were investigated at 600 °C and atmospheric pressure on the fuel and steam conversion, the H₂ yield and the H- and C-products distribution. With a downward fuel feed configuration and using a H₂-reduced catalyst, maximum averaged fuel conversions of ∼97% for pine oil and 89% for EFB oil were achieved at S/C ratios of 2.3 and 2.6 respectively (on a water-free oil basis). This produced H₂ with a yield efficiency of approximately 60% for pine oil and 80% for EFB oil notwithstanding equilibrium limitations, and with little CH₄ by-product. Both oils exhibited very similar outputs with varying S/C. Upon a short number of cycles, i.e. starting from an oil-reduced catalyst, the fuel conversion dropped slightly but the steam conversion was constant, resulting in a slow decrease in H₂ yield. Despite their high level of oxygen content, the pyrolysis oils were shown to maintain close to 90% reduction of the oxidised catalyst upon repeated cycles, but the rate of reduction decreased with cycling.     

Catalytic steam reforming of JP-10 over Ni/SBA-15

As the only H₂ resource on aircraft from the steam reforming of the jet fuels on board, catalytic steam reforming of JP-10 (one of Jet fuels) over nickel-based catalyst Ni/SBA-15 were first carried out in a fixed bed tube reactor to produce hydrogen on-site or on board. A series of Ni/SBA-15 catalysts with different Ni content (3, 5, 8 and 10.8 wt%) were prepared by a modified incipient wetness impregnation method with addition of sucrose as ligand. And the effect of operation conditions of temperature (630–700 °C), nickel loading, liquid hour space velocity (LHSV = 5, 10, 15 ml/g_cat·h), steam to carbon molar ratio (S/C = 3, 5) on the catalytic activity and selectivity was investigated. It was found that 8Ni/SBA-15 was the optimal catalyst for steam reforming of JP-10 even with a higher LHSV and fuel gas concentration, and approximately 100% conversion of JP-10 with over 80% selectivity to hydrogen under the recommended experimental conditions of 680 °C, S/C of 5, LHSV of 10 ml/g_cat·h. The catalytic activity of 8Ni/SBA-15 dropped slowly to 84% after 6.5 h in the stability test and the carbon deposited was less with just 6% mass loss from TGA measurement (coke deposition rate 0.01g_C/g_cath), which ascribed to possible reasons including confine effect of mesochannel of SBA-15, strengthened structure of mesochannels due to embeded Ni particles, and higher temperature to suppress the main carbon producing reaction.     

Hydrogen Production from Carbonaceous Solid Wastes by Steam Reforming

Abstract

In this study, gas and liquid fuels from biomass by steam reforming were investigated. The steam reforming process provides the opportunity to convert renewable biomass materials into clean fuel gases or synthesis gases. Synthesis gas includes mainly hydrogen and carbon monoxide which is also called as syngas (H₂ + CO). Bio-syngas is a gas rich in CO and H₂ obtained by gasification of biomass. The aim of Fischer-Tropsch Synthesis (FTS) is synthesis of long-chain hydrocarbons from CO and H₂ gas mixture. The products from FTS are mainly aliphatic straight-chain hydrocarbons (C_xH_y). The distribution of the products depends on the catalyst and the process parameters such as temperature, pressure, and residence time. Typical operation conditions for the FTS are a temperature range of 475–625 K and pressures of 15–40 bar, depending on the process.     

Thermodynamic analysis of hydrogen production via glycerol steam reforming with CO2 adsorption

Thermodynamic equilibrium for glycerol steam reforming to hydrogen with carbon dioxide capture was investigated using Gibbs free energy minimization method. Potential advantage of using CaO as CO₂ adsorbent is to generate hydrogen-rich gas without a water gas shift (WGS) reactor for proton exchange membrane fuel cell (PEMFC) application. The optimal operation conditions are at 900 K, the water-to-glycerol molar ratio of 4, the CaO-to-glycerol molar ratio of 10 and atmospheric pressure. Under the optimal conditions, complete glycerol conversion and 96.80% H₂ and 0.73% CO concentration could be achieved with no coke. In addition, reaction conditions for coke-free and coke-formed regions are also discussed in glycerol steam reforming with or without CO₂ separation. Glycerol steam reforming with CO₂ adsorption has the higher energy efficiency than that without adsorption under the same reaction conditions.     

A comprehensive review of direct carbon fuel cell technology

Fuel cells are under development for a range of applications for transport, stationary and portable power appliances. Fuel cell technology has advanced to the stage where commercial field trials for both transport and stationary applications are in progress. The electric efficiency typically varies between 40 and 60% for gaseous or liquid fuels. About 30–40% of the energy of the fuel is available as heat, the quality of which varies based on the operating temperature of the fuel cell. The utilisation of this heat component to further boost system efficiency is dictated by the application and end-use requirements. Fuel cells utilise either a gaseous or liquid fuel with most using hydrogen or synthetic gas produced by a variety of different means (reforming of natural gas or liquefied petroleum gas, reforming of liquid fuels such as diesel and kerosene, coal or biomass gasification, or hydrogen produced via water splitting/electrolysis). Direct Carbon Fuel Cells (DCFC) utilise solid carbon as the fuel and have historically attracted less investment than other types of gas or liquid fed fuel cells. However, volatility in gas and oil commodity prices and the increasing concern about the environmental impact of burning heavy fossil fuels for power generation has led to DCFCs gaining more attention within the global research community. A DCFC converts the chemical energy in solid carbon directly into electricity through its direct electrochemical oxidation. The fuel utilisation can be almost 100% as the fuel feed and product gases are distinct phases and thus can be easily separated. This is not the case with other fuel cell types for which the fuel utilisation within the cell is typically limited to below 85%. The theoretical efficiency is also high, around 100%. The combination of these two factors, lead to the projected electric efficiency of DCFC approaching 80% - approximately twice the efficiency of current generation coal fired power plants, thus leading to a 50% reduction in greenhouse gas emissions. The amount of CO₂ for storage/sequestration is also halved. Moreover, the exit gas is an almost pure CO₂ stream, requiring little or no gas separation before compression for sequestration. Therefore, the energy and cost penalties to capture the CO₂ will also be significantly less than for other technologies. Furthermore, a variety of abundant fuels such as coal, coke, tar, biomass and organic waste can be used. Despite these advantages, the technology is at an early stage of development requiring solutions to many complex challenges related to materials degradation, fuel delivery, reaction kinetics, stack fabrication and system design, before it can be considered for commercialisation. This paper, following a brief introduction to other fuel cells, reviews in detail the current status of the direct carbon fuel cell technology, recent progress, technical challenges and discusses the future of the technology.     

Characterization and activity test of commercial Ni/Al2O3, Cu/ZnO/Al2O3 and prepared Ni–Cu/Al2O3 catalysts for hydrogen production from methane and methanol fuels

In this study, methane and methanol steam reforming reactions over commercial Ni/Al₂O₃, commercial Cu/ZnO/Al₂O₃ and prepared Ni–Cu/Al₂O₃ catalysts were investigated. Methane and methanol steam reforming reactions catalysts were characterized using various techniques. The results of characterization showed that Cu particles increase the active particle size of Ni (19.3 nm) in Ni–Cu/Al₂O₃ catalyst with respect to the commercial Ni/Al₂O₃ (17.9). On the other hand, Ni improves Cu dispersion in the same catalyst (1.74%) in comparison with commercial Cu/ZnO/Al₂O₃ (0.21%). A comprehensive comparison between these two fuels is established in terms of reaction conditions, fuel conversion, H₂ selectivity, CO₂ and CO selectivity. The prepared catalyst showed low selectivity for CO in both fuels and it was more selective to H₂, with H₂ selectivities of 99% in methane and 89% in methanol reforming reactions. A significant objective is to develop catalysts which can operate at lower temperatures and resist deactivation. Methanol steam reforming is carried out at a much lower temperature than methane steam reforming in prepared and commercial catalyst (275–325 °C). However, methane steam reforming can be carried out at a relatively low temperature on Ni–Cu catalyst (600–650 °C) and at higher temperature in commercial methane reforming catalyst (700–800 °C). Commercial Ni/Al₂O₃ catalyst resulted in high coke formation (28.3% loss in mass) compared to prepared Ni–Cu/Al₂O₃ (8.9%) and commercial Cu/ZnO/Al₂O₃ catalysts (3.5%).     

Autothermal reforming of n-dodecane and desulfurized Jet-A fuel for producing hydrogen-rich syngas

Catalytic reforming is a technology to produce hydrogen and syngas from heavy hydrocarbon fuels in order to supply hydrogen to fuel cells. A lab-scale 2.5 kW_t autothermal reforming (ATR) system with a specially designed reformer and combined analysis of balance-of-plant was studied and tested in the present study. NiO–Rh based bimetallic catalysts with promoters of Ce, K, and La were used in the reformer. The performance of the reformer was studied by checking the hydrogen selectivity, CO_x selectivity, and energy conversion efficiency at various operating temperatures, steam to carbon ratios, oxygen to carbon ratios, and reactants' inlet temperatures. The experimental work firstly tested n-dodecane as the surrogate of Jet-A fuel to optimize operating conditions. After that, desulfurized commercial Jet-A fuel was tested at the optimized operating conditions. The design of the reformer and the catalyst are recommended for high performance Jet-A fuel reforming and hydrogen-rich syngas production.     

Steam reforming of commercial ultra-low sulphur diesel

Two main routes for small-scale diesel steam reforming exist: low-temperature pre-reforming followed by well-established methane steam reforming on the one hand and direct steam reforming on the other hand. Tests with commercial catalysts and commercially obtained diesel fuels are presented for both processes. The fuels contained up to 6.5 ppmw sulphur and up to 4.5 vol.% of biomass-derived fatty acid methyl ester (FAME). Pre-reforming sulphur-free diesel at around 475 °C has been tested with a commercial nickel catalyst for 118 h without observing catalyst deactivation, at steam-to-carbon ratios as low as 2.6. Direct steam reforming at temperatures up to 800 °C has been tested with a commercial precious metal catalyst for a total of 1190 h with two catalyst batches at steam-to-carbon ratios as low as 2.5. Deactivation was neither observed with lower steam-to-carbon ratios nor for increasing sulphur concentration. The importance of good fuel evaporation and mixing for correct testing of catalysts is illustrated. Diesel containing biodiesel components resulted in poor spray quality, hence poor mixing and evaporation upstream, eventually causing decreasing catalyst performance. The feasibility of direct high temperature steam reforming of commercial low-sulphur diesel has been demonstrated.