Development and testing of anode-supported solid oxide fuel cells with slurry-coated electrolyte and cathode

A laboratory setup was designed and put into operation for the development of solid oxide fuel cells (SOFCs). The whole project consisted of the preparation of the component materials: anode, cathode and electrolyte, and the buildup of a hydrogen leaking-free sample chamber with platinum leads and current collectors for measuring the electrochemical properties of single SOFCs. Several anode-supported single SOFCs of the type (ZrO₂:Y₂O₃ + NiO) thick anode/(ZrO₂:Y₂O₃) thin electrolyte/(La_0.65Sr_0.35MnO₃ + ZrO₂:Y₂O₃) thin cathode have been prepared and tested at 700 and 800 °C after in situ H₂ anode reduction. The main results show that the slurry-coating method resulted in single-cells with good reproducibility and reasonable performance, suggesting that this method can be considered for fabrication of SOFCs.     

Development of durable copper catalyst for hydrogen production by high temperature methanol steam reforming

Highly durable catalyst for high temperature methanol steam reforming is required for a compact hydrogen processor. Deactivation of a coprecipitated Cu/ZnO/ZrO₂ catalyst modified with In₂O₃ is very gradual even in the high temperature methanol steam reforming mainly at 500 °C, but the initial activity is considerably low. Addition of Y₂O₃ to Cu/ZnO/ZrO₂/In₂O₃ increases its initial activity due to the higher Cu surface amount, while the activity comes gradually close to that for the catalyst without Y₂O₃ during the reaction. Coprecipitation of Cu/ZnO/ZrO₂/Y₂O₃/In₂O₃ on a zirconia support triply increases the overall activity by keeping the durability while the amount of the coprecipitated portion is a half of that without the support. On the composite catalyst, sintering of Cu particles is suppressed. The surface Cu amount is similar to that without the support, but the Cu surface activity is much higher probably because of the small Cu particle size.     

Development of a hydrogen dual sensor for fuel cell applications

The development and application of a hydrogen dual sensor (HDS) for the application in the fuel cell (FC) field, is reported. The dual sensing device is based on a ceramic platform head with a semiconducting metal oxide layer (MOx) printed on Pt interdigitated contacts on one side and a Pt serpentine resistance on the back side. MOx layer acts as a conductometric (resistive) gas sensor, allowing to detect low H₂ concentrations in air with high sensitivity and fast response, making it suitable as a leak hydrogen sensor. The proposed Co-doped SnO₂ layer shows high sensitivity to hydrogen (R₀/R = 90, for 2000 ppm of H₂) at 250 °C in air, and with fast response (<3 s). Pt resistance serves as a thermal conductivity sensor, and can used to monitor the whole range of hydrogen concentration (0–100%) in the fuel cell feed line with short response-recovery times, lower than 13 s and 14 s, respectively. The effect of the main functional parameters on the sensor response have been evaluated by bench tests. The results demonstrate that the dual sensor, in spite of its simplicity and cheapness, is promising for application in safety and efficiency control systems for FC power source.     

Hydrogen production from catalytic supercritical water reforming of glycerol with cobalt-based catalysts

Glycerol reforming under catalytic supercritical water at temperatures in the range of 723–848 K using Co catalyst deposited on various supports including ZrO₂, yttria-stabilized zirconia (YSZ), La₂O₃, γ-Al₂O₃, and α-Al₂O₃ was investigated. An increase in operating temperature promoted the continued increase in glycerol conversion; however, carbon formation causing system operation failure was observed for γ-Al₂O₃ and α-Al₂O₃ at high operating temperatures (i.e. 748–798 K). Co supported on YSZ provided the most efficient performance for hydrogen production. 10 wt.% Co loading on YSZ support was an optimum amount to enhance the reaction. The increase in glycerol conversion and reduction of the amount of liquid products were observed for lower weight hourly space velocity (WHSV), higher operating temperature or higher cobalt loading. On Co/YSZ catalyst, glycerol conversion of 0.94 and hydrogen yield of 3.72 was obtained with WHSV of 6.45 h⁻¹at 773 K.     

Nickel catalysts supported on ZrO2, Y2O3-stabilized ZrO2 and CaO-stabilized ZrO2 for the steam reforming of ethanol: Effect of the support and nickel load

Catalysts with various nickel loads were prepared on supports of ZrO₂, ZrO₂–Y₂O₃ and ZrO₂–CaO, characterized by XRD and TPR and tested for activity in ethanol steam reforming. XRD of the supports identified the monoclinic crystalline phase in the ZrO₂ and cubic phases in the ZrO₂–Y₂O₃ and ZrO₂–CaO supports. In the catalysts, the nickel impregnated on the supports was identified as the NiO phase. In the TPR analysis, peaks were observed showing the NiO phase having different interactions with the supports. In the catalytic tests, practically all the catalysts achieved 100% ethanol conversion, H₂ yield was near 70% and the gaseous concentrations of the other co-products varied in accordance with the equilibrium among them, affected principally by the supports. It was observed that when the ZrO₂ was modified with Y₂O₃ and CaO, there were big changes in the CO and CO₂ concentrations, which were attributed to the rise in the number of oxygen vacancies, permitting high-oxygen mobility and affecting the gaseous equilibrium. The liquid products analysis showed a low selectivity to liquid co-products during the reforming reactions.     

Nanostructured CuWO4/WO3-x films prepared by reactive magnetron sputtering for hydrogen sensing

High-purity films consisting of copper tungstate (CuWO₄) and sub-stoichiometric tungsten oxide (WO_3-x) were prepared by reactive sputter deposition. An original two-step deposition process was applied for their synthesis. First, a tungsten oxide thin film was deposited by dc magnetron sputtering from a W target in an Ar + O₂ gas mixture, afterward, rf sputtering of a Cu target in an Ar + O₂ gas mixture was employed to form a discontinuous CuWO₄ layer at the top. This results in a formation of nanostructured branched islands of the tungstate. Bilayers with various layer thicknesses were investigated for the sensitivity to hydrogen gas as a conductometric sensor. The sensitivity changes remarkably with the thicknesses of individual layers. The maximum sensitivity was observed for the films with a layer thickness ratio of 5 nm/20 nm. The response was enhanced more than eight times compared to a 20 nm-thick tungsten oxide alone film. An explanation based on the formation of nano-sized n-n junctions is provided. In addition, a microscopy study of the bilayer growth is presented in detail.     

Stability of Y2O3 hydrogen isotope permeation barriers in hydrogen at high temperatures

Hydrogen isotope permeation barriers (HIPB) have great potential applications in the fields of hydrogen energy and thermonuclear fusion energy. Here, we report the stability of Y₂O₃ HIPB in gaseous hydrogen at high temperatures including the structures, mechanical properties and electrical properties. With increasing hydrogen treatment time at 700 °C, the high-index diffractions of Y₂O₃ became weak gradually whereas the (400) diffraction was strengthened. The color of the Y₂O₃ HIPB changed from brown to gray. The bonding strength decreased by 61% with increasing hydrogen treatment time, and finally remained unchanged. Meanwhile, the electrical resistivity of the Y₂O₃ HIPB decreased from 8.2 × 10⁹ Ω cm by over two orders of magnitude and then tended to be constant. The oxygen loss as well as hydrogen incorporation was proposed to be responsible for these modifications and indications of the present work for preparation of HIPB with high reliability were discussed.     

Synthesis and characterizations of highly responsive H2S sensor using p-type Co3O4 nanoparticles/nanorods mixed nanostructures

High-quality p-type semiconducting Co₃O₄ with mixed morphology of nanoparticles/nanorods are synthesized using a hydrothermal route for high response and selective hydrogen sulphide (H₂S) sensor application. XRD and Raman studies revealed the crystal structure and molecular bonding for obtained Co₃O_4, respectively. The nanoparticles/nanorods-like structures were confirmed for Co₃O₄ using FESEM and TEM analysis. The EDS and XPS spectra analysis were carried out for elemental composition and chemical atomic states of Co₃O₄. The Co₃O₄ sensor is investigated for gas sensing properties in dynamic conditions. The sensor exhibited the highest selectivity towards H₂S among various hydrogen-contained gases at 225 °C. The sensor revealed a high response of 357% and 44% for 100 and 10 ppm H₂S gas concentrations, respectively. The Co₃O₄ sensor exhibited a systematic dynamic resistance response for 100–10 ppm range H₂S gas. The excellent dynamic resistance repeatability of the sensor was shown towards 25 ppm H₂S gas. The response of Co₃O₄ sensor was investigated at different operating temperatures and H₂S concentrations. The sensor stability and H₂S sensing mechanism for the Co₃O₄ sensor have been reported. Highly uniform and mixed nanostructures of Co₃O₄ can be the potential sensor material for real-time high-performance H₂S sensor application.     

H2 production from oxidative steam reforming of 1-propanol and propylene glycol over yttria-stabilized supported bimetallic Ni–M (M = Pt,Ru, Ir) catalysts

This paper reports hydrogen production from oxidative steam reforming of 1-propanol and propylene glycol over Ni–M/Y₂O₃–ZrO₂ (10% wt/wt Y₂O₃; M = Ir, Pt, Ru) bimetallic catalysts promoted with K. The results are compared with those obtained over the corresponding monometallic catalyst. The catalytic performance of the calcined catalysts was analyzed in the temperature range 723–773 K, adjusting the total composition of the reactants to O/C = 4 and S/C = 3.2–3.1 (molar ratios). The bimetallic catalysts showed higher hydrogen selectivity and lower selectivity of byproducts than the monometallic catalyst, especially at 723 K. Ni–Ir performed best in the oxidative steam reforming of both 1-propanol and propylene glycol. The presence of the noble metal favours the reduction of the NiO and the partial reduction of the support. The NiO crystalline phase present in the calcined catalysts was transformed to Ni° during oxidative steam reforming. The adsorption and subsequent reactivity of both 1-propanol and propylene glycol over Ni–Ir and Ni catalysts were followed by FTIR; C–C bond cleavage was found to occur at a lower temperature in propylene glycol than in 1-propanol.     

Exploring MnCr2O4–Gd0.1Ce0.9O2-δ as a composite electrode material for solid oxide fuel cell

Symmetrical solid oxide fuel cell (SOFC) adopting the same material at both electrodes is potentially capable of promoting thermomechanical compatibility between near components and lowering stack costs. In this paper, MnCr₂O₄–Gd_0.1Ce_0.9O_2-δ (MCO-GDC) composite electrodes prepared by co-infiltration method for symmetrical electrolyte supported and anode supported solid oxide fuel cells are evaluated at a temperature range of 650–800 °C in wet (3% H₂O) hydrogen and air atmospheres. Without any alkaline earth elements and cobalt, the co-infiltrated MCO-GDC composite electrode shows excellent activity for oxygen reduction reaction but mediocre activity for hydrogen oxidation reaction. With MCO-GDC as the cathode, the Ni-YSZ (Y₂O₃ stabilized ZrO₂) anode supported asymmetrical cell demonstrates a peak power density of 665 mW cm⁻² at 800 °C. The above results suggest MCO-GDC is a promising candidate cathode material for solid oxide fuel cells.     

Iron incorporated Ni–ZrO2 catalysts for electric power generation from methane

On the purpose to perform as functional layer of SOFCs operating on methane fuel, NiFe–ZrO₂ alloy catalysts have been synthesized and investigated for methane partial oxidation reactions. Ni₄Fe₁–ZrO₂ shows catalytic activity comparable to that of Ni–ZrO₂ and superior to other Fe-containing catalysts. In addition, O₂-TPO analysis indicates iron is also prone to coke formation; as a result, most of NiFe–ZrO₂ catalysts do not show improved coking resistance than Ni–ZrO₂. Anyway, Ni₄Fe₁–ZrO₂ (Ni:Fe = 4:1 by weight) prepared by glycine-nitrate process shows somewhat less carbon deposition than the others. However, Raman spectroscopy demonstrates that the addition of Fe does reduce the graphitization degree of the deposited carbon, suggesting the easier elimination of carbon once it is deposited over the catalyst. Ni₄Fe₁–ZrO₂ has an excellent long-term stability for partial oxidation of methane reaction at 850 °C. A solid oxide fuel cell with conventional nickel cermet anode and Ni₄Fe₁–ZrO₂ functional layer is operated on CH₄–O₂ gas mixture to yield a peak power density of 1038 mW cm⁻² at 850 °C, which is comparable to that of hydrogen fuel. In summary, the Ni₄Fe₁–ZrO₂ catalyst is potential catalyst as functional layer for solid-oxide fuel cells operating on methane fuel.     

Performance and stability of nano-structured Pd and Pd0.95M0.05 (M = Mn,Co, Ce,and Gd) infiltrated Y2O3–ZrO2 oxygen electrodes of solid oxide electrolysis cells

Nano-structured Pd infiltrated and Pd_0.95M_0.05 (M = Mn, Co, Ce, and Gd) co-infiltrated Y₂O₃–ZrO₂ (YSZ) electrodes are studied as the oxygen electrodes of solid oxide electrolysis cells (SOECs). The infiltrated Pd-YSZ electrodes show good electrocatalytic activity for the oxygen evolution reaction. For example, the electrode polarization resistance (R_E) for 2.0 mg cm⁻² Pd infiltrated YSZ is 0.36 Ω cm⁻² at 800 °C. R_E is not significantly affected by co-infiltrating Pd with Mn and Co, but is enhanced by co-infiltration of Ce and Gd. The co-infiltration of low concentrations of metals in particular Co, Ce and Gd significantly enhances the microstructure and performance stability of the Pd-YSZ electrodes. The results demonstrate that the addition of dopants to the Pd in the form of either an alloy (Co) or a separate phase (Ce and Gd) is beneficial to enhance the performance and stability of Pd based oxygen electrodes of SOECs.     

Hydrogen production by steam reforming of liquefied natural gas (LNG) over Ni/Al2O3–ZrO2 xerogel catalysts: Effect of calcination temperature of Al2O3–ZrO2 xerogel supports

Al₂O₃–ZrO₂ (AZ) xerogel supports prepared by a sol-gel method were calcined at various temperatures. Ni/Al₂O₃–ZrO₂ (Ni/AZ) catalysts were then prepared by an impregnation method for use in hydrogen production by steam reforming of liquefied natural gas (LNG). The effect of calcination temperature of AZ supports on the catalytic performance of Ni/AZ catalysts in the steam reforming of LNG was investigated. Crystalline phase of AZ supports was transformed in the sequence of amorphous γ-Al₂O₃ and amorphous ZrO₂ → θ-Al₂O₃ and tetragonal ZrO₂ → (θ + α)-Al₂O₃ and (tetragonal + monoclinic) ZrO₂ → α-Al₂O₃ and (tetragonal + monoclinic) ZrO₂ with increasing calcination temperature from 700 to 1300 °C. Nickel oxide species were strongly bound to γ-Al₂O₃ and θ-Al₂O₃ in the Ni/AZ catalysts through the formation of solid solution. In the steam reforming of LNG, both LNG conversion and hydrogen composition in dry gas showed volcano-shaped curves with respect to calcination temperature of AZ supports. Nickel surface area of Ni/AZ catalysts was well correlated with catalytic performance of the catalysts. Among the catalysts tested, Ni/AZ1000 (nickel catalyst supported on AZ support that had been calcined at 1000 °C) with the highest nickel surface area showed the best catalytic performance. Well-developed and pure tetragonal phase of ZrO₂ in the AZ1000 support played an important role in the adsorption of steam and the subsequent spillover of steam from the support to the active nickel.     

Performance of solid oxide fuel cells based on proton-conducting BaCe0.7In0.3-xYxO3-δ electrolyte

The performances of solid oxide fuel cells with proton conductors BaCe_0.7In_0.3−xY_xO_3−δ (BCIY, x = 0, 0.1, 0.2, 0.3) as electrolytes were investigated in this work. The cell based on BaCe_0.7In_0.2Y_0.1O_3−δ electrolyte showed maximum power outputs of 0.114, 0.204 and 0.269 Wcm⁻² at 600, 650 and 700 °C, respectively. After operating at a constant cell voltage output of 0.5V for 40h, no obvious degradation in performance was observed for the cells based on BaCe_0.7In_0.3O_3−δ and BaCe_0.7In_0.2Y_0.1O_3−δ electrolytes. However, although relatively lower resistances and higher initial power outputs were found for cells based on BaCe_0.7In_0.1Y_0.2O_3−δ and BaCe_0.7Y_0.3O_3−δ electrolytes, rapid cell performance degradations were observed for these two cells. The stability under cell operating conditions remained a challenge for cells using BaCe_0.7In_0.1Y_0.2O_3−δ and BaCe_0.7Y_0.3O_3−δ electrolytes.     

Highly sensitive and stable H2 gas sensor based on p-PdO-n-WO3-heterostructure-homogeneously-dispersing thin film

The film-based gas sensor owning high compatibility with semiconductor device fabrication, plays an important role in the miniaturization and integration of the devices. Here, simple metal organic decomposition method and calcining procedure were used to prepare dense WO₃ thin film with PdO nanoparticles being homogeneously dispersed. After painting the silver paste on its surface as electrodes, the H₂ gas sensor was fabricated. At the optimal operating temperature of 160 °C, with response values (R_a/R_g) of 1.2 & 45.1 and response time of 38 s & 4 s, towards 500 ppb and 100 ppm H₂, respectively, the sensor presents high sensitivity and low detection limit together. It is rare to report the H₂ gas sensor based on dense semiconductor film with such low detection limit. Towards 500 ppb and 100 ppm H₂, it still shows the same response values more than half a year later, which proves its stability. A good linear behaviour between the response and relative humidity is observed too. The chief cause of the better performance of the sensor may be the homogeneous and optimal distribution of the p-type PdO nanoparticles in n-type WO₃ film, which is the character of this structure. In addition, the repeatability of the preparing process is very well too. All the better performances suggest that the H₂ sensor based on this structure has a huge potential in practical application.     

In situ screen-printed BaZr0.1Ce0.7Y0.2O3−δ electrolyte-based protonic ceramic membrane fuel cells with layered SmBaCo2O5+x cathode

In order to develop a simple and cost-effective route to fabricate protonic ceramic membrane fuel cells (PCMFCs) with layered SmBaCo₂O_5+x (SBCO) cathode, a dense BaZr_0.1Ce_0.7Y_0.2O_3?δ (BZCY) electrolyte was fabricated on a porous anode by in situ screen printing. The porous NiO–BaZr_0.1Ce_0.7Y_0.2O_3?δ (NiO–BZCY) anode was directly prepared from metal oxide (NiO, BaCO₃, ZrO₂, CeO₂ and Y₂O₃) by a simple gel-casting process. An ink of metal oxide (BaCO₃, ZrO₂, CeO₂ and Y₂O₃) powders was then employed to deposit BaZr_0.1Ce_0.7Y_0.2O_3?δ (BZCY) thin layer by an in situ reaction-sintering screen printing process on NiO–BZCY anode. The bi-layer with 25 μm dense BZCY electrolyte was obtained by co-sintering at 1400 °C for 5 h. With layered SBCO cathode synthesized by gel-casting on the bi-layer, single cells were assembled and tested with H₂ as fuel and the static air as oxidant. A high open-circuit potential of 1.01 V, a maximum power density of 382 mW cm^?2, and a low polarization resistance of the electrodes of 0.15 Ω cm² was achieved at 700 °C.     

Synthesis strategies of Zr- and Y-promoted mixed oxides derived from double-layered hydroxides for syngas production via dry reforming of methane

Ni-based Mg/Al double-layered hydroxides, also called hydrotalcites (HTs), were co-precipitated with Zr (5 wt%) and impregnated with Y (0.2, 0.4, 0.6 wt%), and compared to the catalyst co-precipitated with both Y (0.4 wt%) and Zr (5 wt%). Their performance in dry reforming of methane was determined in the temperature range of 850–600 °C and stability tests at 700 °C for 5 h. The materials were characterized by X-ray powder diffraction, X-ray fluorescence, nitrogen adsorption/desorption, H₂-TPR, CO₂-TPD, hydrogen chemisorption, thermogravimetric analysis, transmission electron microscopy, high-resolution transmission electron microscopy, and Raman spectroscopy. A decrease in reducibility and lower total number of basic sites were observed for the sample promoted only with zirconia compared to the unpromoted material. After promotion with yttrium, no formation of ZrO₂–Y₂O₃ solid solution was evident from XRD. The Ni dispersion was decreased due to decoration of the surface with Y species, leading to blockage of available nickel sites. All Zr and Y promoted samples were, however, more active in DRM than unpromoted HTNi. The co-precipitated Zr and Y catalyst (HTNi-ZrY0.4-cop) exhibited increasing conversion over time, and a H₂/CO close to 1 in the isothermal test at 700 °C. H₂-TPSR on the spent catalysts revealed that the promotion with yttrium favored regeneration of the catalytic bed, consuming the majority of removable coke and decreasing the formation of unreactive coke.     

Investigation on properties of BaZr0.6Hf0.2Y0.2O3-δ with sintering aids (ZnO,NiO, Li2O) and its application for hydrogen permeation

BaZr_0.8Y_0.2O_3-δ proton conductor has the characteristics of excellent chemical stability, but its impoverished sinterability and low conductivity hinder its applications in fuel cell and hydrogen separation. Hf doping in Zr site improves BaZr_0.6Hf_0.2Y_0.2O_3-δ sinterability and conductivity. To further enhance BaZr_0.6Hf_0.2Y_0.2O_3-δ properties, three kinds of sintering aids ZnO, NiO or Li₂O were introduced and their effect on the sinterability, microstructure and conductivity of BaZr_0.6Hf_0.2Y_0.2O_3-δ were studied. The experimental results display that 4 mol% ZnO can enhance the sinterability and conductivity of BaZr_0.6Hf_0.2Y_0.2O_3-δ sample sintered at 1400 °C. Compared with BaZr_0.6Hf_0.2Y_0.2O_3-δ sintered at 1600 °C, BaZr_0.6Hf_0.2Y_0.2O_3-δ with 4 mol% ZnO is of larger grain size, higher relative density (95.5%) and lower sintering temperature (reducing by 200 °C). Meanwhile, the conductivity of BaZr_0.6Hf_0.2Y_0.2O_3-δ with 4 mol% ZnO reaches 4.17 × 10^?3 S cm^?1 in wet 5% H₂/Ar at 700 °C, due to the reduction of the grain boundary resistance of sample. BaZr_0.6Hf_0.2Y_0.2O_3-δ with 4 mol% ZnO membrane for hydrogen separation via external short circuit was developed. The membrane with a thickness of 1.08 mm gives a hydrogen permeation flux of 0.098 mL min^?1cm^?2 at 800 °C with 50% H₂/He as feed gas. The presence of water vapor significantly promotes the hydrogen permeability of the membrane. In addition, introduction of 3% CO₂ or 100 ppm H₂S into feed gas does not decrease the hydrogen permeation flux of the membrane.     

Methane decomposition over Fe-based catalysts

Catalytic approach for methane decomposition can be seriously considered as a promising process for CO_x free hydrogen generation. In this study, catalytic methane decomposition was performed using Fe-based catalysts, and catalytic performance tests were carried out in a CH₄:N₂ flow at 750 and 800 °C. The analyses of reaction products were carried out by a mass spectrometer. For the preparation of Fe-based catalysts, sol-gel method was utilized. Yttria (Y₂O₃) and alumina (Al₂O₃) were used as support materials. Theoretical molar ratios (Fe₂O₃/Y₂O₃/Al₂O₃) of the samples C1–C5 were 1:0:0, 1:1:0, 1:1:5, 2:1:4 and 3:1:6, respectively. The characterization analyses of fresh and spent catalysts were performed with XRD, SEM, TPR, TG-FTIR and BET surface analysis techniques. Surface basicity of catalysts was determined via CO₂-TPD measurements. In the presence of Fe₂O₃/Y₂O₃ and Fe₂O₃/Y₂O₃/Al₂O₃ catalysts, methane conversions of 29% and 4% were achieved at 750 °C. Adding alumina into Fe₂O₃/Y₂O₃ catalyst leads to the formation of garnet type crystal structure which reduces catalytic activity.     

Absorption enhanced reforming of light alcohols (methanol and ethanol) for the production of hydrogen: Thermodynamic modeling

Thermodynamic modeling of the steam reforming of light alcohols using CaO, CaO*MgO, Na₂ZrO₃, Li₂ZrO₃ and Li₄SiO₄ as CO₂ absorbents was carried out to determine promising operating conditions to produce a high hydrogen yield (YH₂)$\left(Y_{{\text{H}}_2}\right)$ and concentration (% H₂). Ethanol and methanol were studied at 300–800 °C and 1 atm. Steam to alcohol (S/COH) feed molar ratio varied from 1:1 (stoichiometric) to 6:1 for methanol and from 3:1 (stoichiometric) to 6:1 for ethanol. Thermodynamic simulations employed the Gibbs free energy minimization technique. Results indicate no carbon formation at S/COH ≤ stoichiometric. For both alcohols reforming at 600 °C and S/COH = 6, using CaO, CaO*MgO, and Na₂ZrO₃ produced optimal YH₂$Y_{{\text{H}}_2}$ and hydrogen purity (% H₂). In both reforming systems most favorable thermodynamics were obtained with CaO, CaO*MgO and Na₂ZrO₃ as absorbents. A Thermal efficiency analysis performed in all system confirmed the superiority of the CO₂ absorption systems against conventional reforming processes.