Steam Reforming Of Propane Research Articles

Effective hydrogen production from propane steam reforming over bimetallic co-doped NiFe/Al2O3 catalyst

Abstract In this study, we investigated the role of Fe oxide as a promoter to improve the redox properties of Ni in PSR (propane steam reforming), thereby extending its lifetime and enabling it to be more easily oxidized by the CO generated to produce CO 2 . Bimetallic NiFe supported on γ-Al 2 O 3 (30Ni x Fe y O/70Al 2 O 3 ) samples are prepared as catalysts and characterized by XRD, TEM, H 2 -TPR, TPO, and XPS. Moreover, a mechanism for propane steam reforming over the 30Ni x Fe y O/70Al 2 O 3 catalyst is proposed on the basis of the GC and mass spectroscopy results and CO-, C 3 H 8 -, and H 2 O-temperature programmed desorption analysis. Consequently, the Fe components in the 30Ni x Fe y O/70Al 2 O 3 catalysts suppressed the agglomeration between the Ni and Al particles. The catalytic performances on the 30Ni x Fe y O/70Al 2 O 3 catalysts are improved by the reduced deposition of carbon compared to that on the 30NiO/70Al 2 O 3 one: at 700 °C, the hydrogen selectivity amounted to 86% in the 30Ni 0.8 Fe 0.2 O/70Al 2 O 3 catalyst compared to 79% in the 30NiO/70Al 2 O 3 one.

Thermodynamic Modeling of Propane Reforming Processes to Quantify Hydrogen and Syngas Production with and without Product Removal

Abstract The present study aims to explore the possibility of promoting hydrogen and syngas production capacity and quality by steam (SRP) and oxidative steam (OSRP) reforming of propane with and without H2 and CO2 removal. Conditions studied are temperature range of 600–1,100 K under atmospheric pressure with steam to propane feed ratio (WPR) of 1–18, oxygen to propane feed ratio (OPR) and fractional removal of H2 and CO2 (f) ranging from 0–0.99. The results indicate that SRP with 99% H2 removal produces high H2 yield of 9.93 moles close to theoretical value of 10 moles at relatively low temperature (750 K) than SRP (950 K). Approximately identical results are achieved at 950 K with 99% CO2 removal at same conditions of WPR (12), pressure (1 atm), and complete conversion of propane. Thus, SRP with H2 removal is more energy saving process. In OSRP, lower OPR, higher WPR minimize CO and CH4 production but at the expense of H2 production. However, OSPR process is the most suitable process to provide most favourable H2/CO ratio in syngas. Molar H2/CO ratio in syngas in the range of 1–3 are found at T≥1,000 K, WPR≤6 in SRP, SRP with H2 removal (f=0.4–0.99) and OSRP (OPR=0.2–2). Thermal efficiency is higher than 80% in both SRP with H2 or CO2 removal than SRP(69.39%). The thermal efficiency in OSRP is less than 69%. Hence, propane reforming process in hydrogen selective membrane reactor, provides high quality of hydrogen at relatively lower energy utilization.

In situ Raman spectroscopic analysis of the coking resistance mechanism on SrZr0.95Y0.05O3−x surface for solid oxide fuel cell anodes

While the coking resistance of Ni/yttria-stabilized zirconia (YSZ) anodes in solid oxide fuel cells (SOFCs) toward hydrocarbon fuel can be improved by adding SrZr0.95Y0.05O3−x (SZY) as a proton conductor, the exact mechanism is still unclear. In this study, the surface chemistry of SZY is investigated using in situ Raman spectroscopy to clarify the coking resistance mechanism. Upon exposure to dry propane at 500 °C, the intensity of the Raman peaks corresponding to CO3 species decreases with time, suggesting that the surface-located CO3 groups are consumed through a reaction with deposited carbon or dry reforming of propane, which reduces the tendency of coking. These consumed CO3 groups can then be regenerated through a reaction between water vapor and deposited carbon. The presence of adsorbed water on SZY, which facilitates a carbon removal reaction and the steam reforming of propane, is confirmed by thermogravimetric analysis (TGA). The reactivity of the CO3 groups and the adsorbed water on SZY thus contribute to removing deposited carbon, resulting in the improved coking resistance of Ni/YSZ-SZY anode.

Spectroscopic characterization and catalytic activity of Rh supported on CeO2-modified Al2O3 for low-temperature steam reforming of propane

The present work aims at clarifying the effects of CeO2 addition to Al2O3 support on the surface chemical characteristics and catalytic activity of supported Rh catalysts for low-temperature steam reforming of propane. Steam reforming of propane was carried out at 500°C over Rh catalysts supported on alumina modified with different CeO2 loading (0, 5, 10, 20, 50, 75, and 100wt%). The Rh catalyst supported on 20wt% CeO2-modified alumina (2Rh/20CeAl) showed the highest propane and steam conversions, followed in decreasing order by those with 10, 5, 50, 75, 0, and 100wt% CeO2. TPR results show that the interaction between ceria and rhodium improves the reducibility of both rhodium oxide and ceria. XPS analysis indicates strong ceria–alumina interaction and strong Rh-support interaction for Rh catalysts with CeO2 loading less than 20wt%. Field-Emission SEM and AES results revealed that at 20wt% CeO2 loading, ceria was dispersed as separate nano-particles with sizes of 100–200nm on the alumina surface. At high CeO2 loading (≥50wt%) ceria particles formed conglomerates covering alumina surface. The 2Rh/20CeAl catalyst showed the highest activity for propane steam reforming possibly because the high CeO2 dispersion created a large area of ceria–alumina interface which helped increase Rh dispersion, and the strong interaction between Rh and support helped enhance the reducibility of ceria and rhodium oxide. Rh loaded onto the interfacial region of ceria and alumina is considered to be most active for the 2Rh/20CeAl catalyst.

Modeling of high-temperature reforming reactor based on interactive thermal control with a tail gas combustor

This paper proposes a method to model hydrocarbon reforming by coupling detailed chemical kinetics with complex computational fluid dynamics. The entire chemistry of catalyzed reactions was confined within the geometrically simple channels and modeled using the low-dimensional plug model, into which the interactive thermal control of the multi-channel reforming reactor has been implemented with a tail-gas combustor around the external surface of these catalytic channels. The geometrically complex flow in the tail gas combustor was simulated using FLUENT without involving any chemical reactions. The influences of the conditions at the reactor inlet such as the inlet gas velocity, the inlet gas composition and the variety of hydrocarbons of each channel on gas conversions were investigated numerically. The impact of the tail gas combustor setup on the efficiency of the reforming reactor was also analyzed. Methane catalytic partial oxidation (CPO x ) and propane steam reforming (SR) were used to illustrate the approach reported in the present work.

Comparative study of propane steam reforming in vanadium based catalytic membrane reactor with nickel-based catalysts

The performance of catalytic membrane reactor with Pd-coated V membrane was examined for steam reforming of propane. The long term reforming experiment confirmed the stability of the V membrane with high hydrogen selectivity and permeability. The effect of types of hydrogen permeable membranes on the performance of the catalytic membrane reactor was studied by comparing Pd-coated V, Pd–23Ag, and Pd–10Ag membranes. The types of hydrogen separation membranes (i.e. hydrogen removal rates) did not have a marked effect on the propane conversion rates, while the product compositions were largely influenced by the hydrogen removal rate. Varying metal oxide supports of Ni-catalysts resulted in significant differences in the product compositions. Further, the evaluation of various catalyst-support systems (9wt%Ni–1wt%M/CeO2, M = Co, Pt, Ag, Ru) revealed that hydrogen yield was the highest when 1wt%Ag was added to Ni/CeO2. However, it was also found that excessive secondary metal additions can have negative impact on the catalytic behaviour of parent catalysts.

Low temperature catalytic steam reforming of propane–methane mixture into methane-rich gas: Experiment and macrokinetic modeling

Steam reforming of propane–methane mixture into methane-rich gas was studied in a fixed-bed continuous-flow reactor in a temperature interval of 150–325°C under atmospheric pressure over Ni-based catalyst. It was found that the catalyst had good performance under low steam-to-carbon ratio of 0.39–0.58 and provided equilibrium product distribution at GHSV=670–3100h−1. Macrokinetic modeling of the experimental data obtained was performed in the framework of isothermal plug-flow reactor model. For the first time the two-step macro-kinetic scheme was suggested, that includes the reactions of irreversible propane steam reforming (first-order on propane): C3H8+6H2O→3CO2+10H2 with activation energy 112kJ/mole and reversible CO2 methanation (first-order on hydrogen): CO2+4H2⇄ CH4+2H2O with activation energy 50kJ/mole. It was shown that the proposed scheme describes quantitatively all the experimental results.

Thermodynamic Analysis of Propane Aromatization

Chemical equilibria of propane aromatization under both unrestricted coke-formation and coke-free operating conditions were studied. In both cases, propane conversions were nearly complete. The aromatics selectivity was observed to be 46% at a temperature of 823 K (1 bar) under coke-free operating conditions. Application of hydrogen and steam as coke-removing agents was also studied. Under coke-free operation, the presence of low level of water in the feed favors propane methanation, whereas higher levels of water enhance propane steam reforming. Methane selectivity was found to attain a maximum at H2O/C3H8 molar ratio equal to 0.75 (823 K, 1 bar). The outcomes of the present study imply that the products selectivity has to be controlled kinetically and that the catalyst formulation should be aimed at minimization of coke formation and carbon-carbon bond breakage activity.

Novel Nickel Catalysts Based on Spinel-Type Mixed Oxides for Methane and Propane Steam Reforming

Novel nickel catalysts based on magnesium aluminate spinel-type mixed oxides are developed as hydrocarbon reforming catalysts for hydrogen supply to polymer electrolyte fuel cells. The spinel catalysts were prepared by co-precipitation and the Pechini method, and the spinels prepared by the former method exhibited higher activity for methane steam reforming. The effect of spinel composition, Mg1−xNixAl2O4 (x=0.17, 0.35, 0.50, 0.70, 1) was investigated on the activity and resistance to carbon deposition in steam reforming reaction. The turnover frequency for methane steam reforming at a steam-to-carbon (S/C) ratio of 2 increased with increase in the x value from 0.17 to 0.35, and then gradually decreased with further increase in the nickel content. The carbon deposition tolerance of the spinel catalysts was examined in propane steam reforming at S/C=1 and 600°C. The propane conversion during the reaction was ca. 98% over all catalysts tested, and the amount of deposited carbon, determined as carbon dioxide by temperature programmed oxidation, was least at x=0.17, which is 1/8 of that deposited on a conventional Ni/γ-Al2O3 catalyst. The spinels with x≤0.5 exhibited smaller amounts of carbon deposition, and thus superior tolerance to deactivation.

On-Paper Synthesis of Nickel Nanoparticles and Catalytic Propane Steam Reforming for Efficient Hydrogen Production

Nickel nanoparticles (NiNPs) were successfully synthesized in situ on a microstructured paper matrix composed of inorganic fibers as the main framework and zinc oxide (ZnO) whiskers as a preferential support for NiNPs. The paper-like inorganic fiber/ZnO whisker composites were prepared using a high-speed and low-cost papermaking technique, and then simply immersed in an aqueous solution of Ni(NO3)2. After reduction in hydrogen flow, NiNPs with a fine size about 20 nm in diameter were selectively formed on the ZnO whiskers in the paper composites. As-prepared NiNPs@ZnO paper is much like an ordinary paper product, being flexible, lightweight, and easy to handle. The NiNPs@ZnO paper composites exhibited excellent catalytic performance in the steam reforming of propane, and produced hydrogen more efficiently than commercial pellet-type nickel catalysts. These results are possibly attributed both to highly active NiNPs synthesized in situ and to the uniform flow of reactants inside a microporous paper structure.

Thermally reduced graphene oxide-supported nickel catalyst for hydrogen production by propane steam reforming

Pristine (GO) and thermally reduced graphene oxide (TRGO)-supported nickel catalysts were prepared by a deposition–precipitation (DP) method with a constant loading amount of 20wt% Ni. According to the nature of the GO and TRGO supports, nickel catalysts with different morphologies were formed on the graphene supports. The prepared samples were characterized by BET surface area, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. The morphological characterization studies revealed the formation of plate-like particles in the TRGO supports, whereas spherical particles were obtained by decorating the GO with nickel nanoparticles. The performance of the synthesized catalysts in the steam reforming of propane was compared to the performance of a nickel over alumina (Ni-Al2O3) commercial catalyst (FCR4, Sud-chem, USA). Ni-TRGO showed the best results in terms of H2 conversion when compared to the Ni-GO and commercial catalysts. The results revealed that the amount of the Ni0 state, metal dispersion, and particle size played main roles in the catalyst performance, rendering Ni-TRGO as the most promising among the catalysts studied for the steam reforming of propane.

Application of rhodium nanoparticles for steam reforming of propane in microchannels

Rhodium nanoparticles were synthesized by means of the chemical reduction method and applied as precursor for the preparation of Rh/Al2O3 catalysts with different Rh content (1, 2.5 and 5wt.%). High surface area alumina powder was impregnated with the nanoparticle solution. After drying and calcination, the catalyst powder was deposited in microchannels by means of a washcoating process and after repeated drying and calcination tested for steam reforming of propane. All catalysts showed full conversion at the reaction conditions applied (T=750°C, S/C=4, WHSV=120 Nl/(h*gcat)) including during mid-term tests of 140h uninterrupted testing.

Influence of Terbium Doping on Oxygen Storage Capacity of Ceria–Zirconia Supports: Enhanced Durability of Ni Catalysts for Propane Steam Reforming

Systematic studies were conducted to understand the influence of Tb doping on durability of Ni-based catalysts supported onto Ce0.75−xZr0.25TbxO2 (CZT x , x = 0.0–0.2), prepared by glycine-nitrate process. Ni metals were deposited onto the as-synthesized supports using a solvothermal method. The prepared supports and catalysts were characterized by a number of ex-situ techniques including X-ray powder diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, H2-temperature-programmed reduction and Brunauer–Emmett–Teller analyses. These studies along with soot oxidation experiments confirmed that the existence of Tb3+ and/or Ce3+ ions made significant contribution to enhancing oxygen storage capacity (OSC) of the Tb doped CeO2–ZrO2 based materials, and among all the supports studied, Ce0.65Zr0.25Tb0.1O2 (x = 0.1, CZT 0.1 ) showed the highest OSC. To assess the performance of these catalysts, steam reforming reactions of propane were further carried out on the Ni supported catalysts (Ni/CZT x ) at a steam-to-carbon ratio of 1.5, a gas hourly spaced velocity of 45,000 h−1, and a reaction temperature of 700 °C. Consistent with the determined OSC of the catalysts, the durabilities of the Ni/CZT x catalysts were found to be increased in the order of Ni/CZT 0.1 > Ni/CZT 0.15 > Ni/CZT 0.2 > Ni/CZT 0.05 > Ni/CZ. In particular, the activity of Ni/CZT 0.1 was maintained to be >99 % of propane conversion at least for 200 h without significant deactivation.

Catalytic Steam Reforming of Propane over Ni/LaAlO3 Catalysts: Influence of Preparation Methods and OSC on Activity and Stability

To develop an efficient catalyst for steam reforming of propane, Ni/LaAlO3 catalysts were prepared by deposition precipitation, impregnation, and solvo-thermal methods, and characterized by XRD, BET, H2-TPR, elemental analyses, and TEM. Ni/Al2O3 and Ni/CeO2 catalysts were also synthesized by the solvo-thermal method for comparison. The Ni/LaAlO3 catalysts exhibited better catalytic performance than both Ni/Al2O3 and Ni/CeO2 catalysts, and activities with Ni/LaAlO3 were found to be dependent upon the preparation methods. In particular, the Ni/LaAlO3 catalyst synthesized by the solvo-thermal method exhibited the highest activity presumably because tetrahydrofuran helps distribute generated Ni nanoparticles onto the catalyst surface in a uniform fashion. In addition, the solvo-thermally prepared Ni/LaAlO3 catalyst was found to be highly stable, with its activity being maintained at least during 100 h. The observed high stability is attributed to the excellent oxygen storage capacity of LaAlO3, which was first determined by thermogravimetric methods as well as by soot oxidations in the presence of Al2O3, CeO2, and LaAlO3. Compared to the Ni/Al2O3 and Ni/CeO2 catalysts, Ni/LaAlO3 exhibited suppressed carbon formation even at lower S/C ratios due to the superior oxygen transport ability of the LaAlO3 support.

La0.7Sr0.3Cr1-xNixO3Perovskite 촉매의 프로판 수증기 개질 반응에서의 특성 연구

<TEX>$LaCrO_{3}$</TEX>를 기본으로 하는 perovskite형 재료인 <TEX>$La_{0.7}Sr_{0.3}Cr_{1-x}Ni_{x}O_{3}$</TEX>(0.1 <TEX>${\leq}$</TEX> x <TEX>${\leq}$</TEX> 0.5)를 citric acid와 EDTA를 이용한 졸-겔법(sol-gel method)으로 합성하였다. 제조한 촉매의 특성분석은 BET, XRD, SEM, <TEX>$H_2$</TEX>-TPR, EA 그리고 TEM을 이용하였고, 프로판 수증기 개질 반응을 통하여 촉매 활성을 평가하였다. Perovskite 산화물의 A-site에는 Sr을 30 ml% 고정치환하고, B-site에 Ni 치환양을 증가시키면서 프로판 수증기 개질 반응 실험을 수행한 결과 Ni 치환양과 S/C의 비(steam to carbon ratio)가 증가할수록 프로판 전환율과 수소 수율이 향상되었다. <TEX>$La_{0.7}Sr_{0.3}Cr_{0.5}Ni_{0.5}O_{3}$</TEX>(LSCN-0.5)촉매가 S/C의 비가 1.7이고, <TEX>$800^{\circ}C$</TEX>의 반응온도 조건에서 100%의 프로판 전환율과 95.9%의 높은 수소 수율을 나타내어 가장 좋은 촉매 활성을 보였다. 반응 후의 촉매에서는 filamentous cabon형태의 탄소 침적형태가 나타나며, Ni 치환양이 증가할수록 침적되는 탄소의 양이 증가하는 것을 확인하였다. The <TEX>$La_{0.7}Sr_{0.3}Cr_{1-x}Ni_{x}O_{3}$</TEX>(LSCN-x) perovskites were prepared by citric acid and EDTA using a sol-gel method. The LSCN-x was characterized by BET, XRD, SEM, <TEX>$H_2$</TEX>-TPR, EA and TEM. The catalytic performance of LSCN-x catalysts in steam reforming of propane in the temperature range 600~<TEX>$800^{\circ}C$</TEX> was investigated. Propane conversion and hydrogen yield increased with an increase in the amount of added Ni up to x=0.5 in the B-site, denoted as LSCN-0.5, under S/C=1 and S/C=1.7 reaction conditions. The LSCN-0.5 catalyst exhibited the best performance under Ni-substitution of which propane conversion and hydrogen yield was 100%, 95.9% at <TEX>$800^{\circ}C$</TEX> in the S/C=1.7 condition, respectively. The morphology of carbon deposited on the catalysts after reaction exhibited filamentous carbon and amount of carbon deposited on the catalysts after reaction increased with an increase in the amount of added Ni.

Multiwalled carbon nanotubes-supported Nickel catalysts for the steam reforming of propane

Multiwalled carbon nanotubes (MWCNTs)-supported nickel catalysts with different metal-loading contents were synthesized trough deposition–precipitation (DP) method for its subsequent performance study on steam reforming reaction of propane. The metal-loading content was set at 5, 10, 20, and 25% of nickel. Results showed that 20 wt% nickel oxide over MWCNTs (20% NiO/MWCNTs) had the best performance, on the propane steam reforming reaction, in terms of H2 conversion comparing with the rest of the NiO/MWCNTs catalysts (5, 10, 25 wt% Ni) and a nickel over alumina (Ni/Al2O3) commercial catalyst. The features of the NiO/MWCNTs catalysts were studied trough FT-IR, Raman spectroscopy, N2 adsorption–desorption isotherms, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy measurements. The results evidenced that optimum relation between Ni content, Ni dispersion, and particle size played a main role in the catalyst performance, rendering the 20% NiO/MWCNT as the most promising, among the catalysts studied, for the steam reforming of propane.

The promotion effect of catalytic activity by Ru substitution at the B site of La1−x Sr x Cr1−y Ru y O3−z for propane steam reforming

A series of La1−x Sr x Cr1−y Ru y O3−δ (0.1 ≤ x ≤ 0.5, 0.05 ≤ y ≤ 0.15) materials was prepared by the sol–gel method to develop alternative catalysts for propane steam reforming. Catalyst characteristics were evaluated using physicochemical methods including X-ray diffraction, Brunauer–Emmett–Teller methods, H2 temperature-programmed reduction, and thermogravimetry analysis (TGA). Effects of the amount of ruthenium (Ru) and strontium and the steam-to-carbon ratio (S/C) were investigated. An increase in Ru content led to increased propane conversion and H2 yield, especially below 700 °C. Dramatic enhancement of catalytic activity was observed with La0.8Sr0.2Cr0.85Ru0.15O3 under 600 °C, achieving propane conversion over 79% between 600 and 800 °C with maximum propane conversion and H2 yield of 98.3% and 63.3%, respectively. Also, good resistance to carbon formation for the La0.8Sr0.2Cr0.85Ru0.15O3 catalyst was confirmed by long-term testing and TGA analysis.

Surface reactivity of LaCoO3 and Ru/LaCoO3 towards CO, CO2 and C3H8: Effect of H2 and O2 pretreatments

The differences in surface reactivity of LaCoO3 and Ru/LaCoO3 solids after pre-treatment in a hydrogen or oxygen gas atmosphere towards oxidative steam reforming (OSR) of propane was probed by performing temperature-programmed desorption (TPD) of CO and CO2, temperature-programmed surface reaction (TPSR) of C3H8, transient isothermal oxidation of “carbon” formed after TPSR of C3H8, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) studies. The TPD of CO and CO2 studies revealed a greater adsorption of these molecular product species of the OSR of propane on the surface of LaCoO3 than Ru/LaCoO3 solid, while XPS studies performed after reduction in hydrogen revealed a higher concentration of Co2+ in the LaCoO3 than Ru/LaCoO3 solid catalyst composition. The Ru/LaCoO3 solid was found to exhibit after an induction period enhanced reactivity towards H2 production for the OSR of propane reaction compared to LaCoO3 after hydrogen reduction at 750°C. These results led to the conclusion that the introduction of a small amount of Ru (0.8wt%) on lanthanum cobaltite surface leads to a higher concentration of metallic cobalt (Co0) after hydrogen reduction is performed, thus favouring the enhancement of necessary active catalytic sites on the Co, LaCoO3 and La2O3 surfaces formed. TPSR of propane used as model compound of diesel revealed the participation of surface lattice oxygen of both LaCoO3 and Ru/LaCoO3 pre-oxidized solids as well as the formation of hydrogen by reaction of propane on the Co0 (metallic state) surface once the latter is formed. A greater reactivity of propane during TPSR was observed over the Ru/LaCoO3 solid surface for either oxidative or reductive pre-treatments. Also, a lower amount (2.13mmol/g) of “carbon” deposition was found on Ru/LaCoO3 compared to LaCoO3 (3.65mmol/g) at the end of the TPSR of propane experiment. These results provide important fundamental information on the role of Ru in the Ru/LaCoO3 system towards catalytic oxidative steam reforming of propane.

Hydrogen production by sorption enhanced steam reforming of propane: A thermodynamic investigation

Thermodynamic features of hydrogen production by sorption enhanced steam reforming (SESR) of propane have been studied with the method of Gibbs free energy minimization and contrasted with propane steam reforming (SR). The effects of pressure (1–5 atm), temperature (700–1100 K) and water to propane ratio (WPR, 1–18) on equilibrium compositions and carbon formation are investigated. The results suggest that atmospheric pressure and a WPR of 12 are suitable for hydrogen production from both SR and SESR of propane. High WPR is favourable to inhibit carbon formation. The minimum WPR required to eliminate carbon production is 6 in both SR and SESR. The most favourable temperature for propane SR is approximately 950 K at which 1 mol of propane has the capacity to produce 9.1 mol of hydrogen. The optimum temperature for SESR is approximately 825 K, which is over 100 K lower than that for SR. Other key benefits include enhanced hydrogen production of nearly 10 mol (stoichiometric value) of hydrogen per mole of propane at 700 K, increased hydrogen purity (99% compared with 74% in SR) and no CO 2 or CO production with the only impurity being CH 4, all indicating a great potential of SESR of propane for hydrogen production.

Thermodynamic analysis of hydrogen production for fuel cell via oxidative steam reforming of propane

A thermodynamic analysis of hydrogen production from propane by oxidative steam reforming (OSR) is performed with a Gibbs free energy minimization method. Addition of oxygen reduces the enthalpy of the system and facilitates the heat supply. Equilibrium compositions of OSR as a function of temperature (300, 500, 700 and 900 °C), H 2O/C 3H 8 ratio (1.0–20.0) and O 2/C 3H 8 ratio (0.0–2.0) under oxidative and thermo-neutral (TN) conditions are evaluated. The results for oxidative conditions demonstrate that at 700 °C with H 2O/C 3H 8 ratios above 7.0 and/or O 2/C 3H 8 ratios higher than 1.3 are beneficial for hydrogen production which facilitates superior hydrogen yield, i.e. close to 9.0 mol/mol propane, with coke and methane formation reactions being suppressed effectively. For TN condition, autothermal temperature and equilibrium composition have a stronger dependence on O 2/C 3H 8 ratio than on H 2O/C 3H 8 ratio. Further calculations show that the condition at 700 °C with an appropriate H 2O/C 3H 8 ratio between 7.0 and 13.0 is favorable for achieving a high hydrogen yield and a low carbon monoxide yield. Therefore, a favorable operational range is proposed to ensure the most optimized product yield.