Ni–Mg and Ni–Cu–Mg catalysts for simultaneous production of hydrogen and carbon nanofibers: The effect of calcination temperature

In this paper, we studied the thermocatalytic decomposition of methane using NiMg and NiCuMg catalysts prepared by fusion of the corresponding nitrates in a fixed-bed reactor. The effects of calcination temperature (450, 600, 800 and 1000 °C) and the effect of copper on the hydrogen yields, as well as the properties of both the catalyst before and after use and the deposited carbon, were studied. In all cases, NiCuMg catalysts showed a high and almost constant hydrogen production yield without signs of catalyst deactivation after 8 h on-stream. The performance of NiMg catalysts without Cu became highly influenced by the calcination temperature used. At calcination temperatures higher than 600 °C, a solid solution NiO·MgO$\text{NiO}·\text{MgO}$ was apparently formed in high extension, leading to a fast catalyst deactivation. The structural properties of the obtained carbon nanofilaments were highly dependent on the presence of Cu and on the calcination temperature, as the presence of copper and low calcination temperatures promote the formation of a well-ordered graphitic carbon. Conversely, NiMg catalysts without Cu and, especially, high calcination temperatures enhanced the formation of a disordered turbostratic carbon.     

Effect of calcination temperature of mesoporous alumina xerogel (AX) supports on hydrogen production by steam reforming of liquefied natural gas (LNG) over Ni/AX catalysts

Mesoporous alumina xerogel (AX) supports prepared by a sol–gel method were calcined at various temperatures. Ni/mesoporous alumina xerogel (Ni/AX) catalysts were then prepared by an impregnation method, and were applied to the hydrogen production by steam reforming of liquefied natural gas (LNG). The effect of calcination temperature of AX supports on the catalytic performance of Ni/AX catalysts in the steam reforming of LNG was investigated. Physical and chemical properties of AX supports and Ni/AX catalysts were strongly influenced by the calcination temperature of AX supports. Crystalline structure of AX supports was transformed in the sequence of γ-alumina → (γ + θ)-alumina → θ-alumina → (θ + α)-alumina with increasing calcination temperature from 700 to 1000 °C. Nickel species were strongly bonded to the divalent vacancy of γ-alumina, (γ + θ)-alumina, and θ-alumina through the formation of nickel aluminate phase. 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 AX supports. Among the catalysts tested, Ni/AX-900 (nickel catalyst supported on AX that had been calcined at 900 °C) showed the best catalytic performance. The smallest nickel crystalline size and the strongest nickel–alumina interaction were responsible for high catalytic performance of Ni/AX-900 catalyst in the steam reforming of LNG.     

Preparation of nanocrystalline metal (Cr,Al, Mn,Ce, Ni,Co and Cu) modified ferrite catalysts for the high temperature water gas shift reaction

Water gas shift reaction is an essential process of hydrogen production and carbon monoxide removal from syngas. Fe–Cr–Cu catalysts are typical industrial catalysts for high temperature water gas shift reaction but have environmental and safety concerns related to chromium content. In this work nanocrystalline metal (M)-modified ferrite catalysts (M = Cr, Al, Mn, Ce, Ni, Co and Cu) for replacement of chromium were prepared by coprecipitation method and the effects of promoters on the structural and catalytic properties of the iron based catalysts were studied. Prepared catalysts were characterized using X-ray diffraction (XRD), N₂ adsorption (BET), temperature-programmed reduction (TPR) and transmission electron microscopies (TEM) techniques. Temperature-programmed reduction measurements inferred that copper favors the active phase formation and significantly decreased the reduction temperature of hematite to magnetite. In addition, water gas shift activity results revealed that Fe–Al–Cu catalyst with Fe/Al = 10 and Fe/Cu = 5 weight ratios showed the highest catalytic activity among the prepared catalysts. Moreover, the effect of calcination temperature, GHSV and steam/gas ratio on the catalytic performance of this catalyst was investigated.     

Ni–SiO2 and Ni–Fe–SiO2 catalysts for methane decomposition to prepare hydrogen and carbon filaments

Active and stable Ni–Fe–SiO₂ catalysts prepared by sol–gel method were employed for direct decomposition of undiluted methane to produce hydrogen and carbon filaments at 823 K and 923 K. The results indicated that the lifetime of Ni–Fe–SiO₂ catalysts was much longer than Ni–SiO₂ catalyst at a higher reaction temperature such as 923 K, however, a reverse trend was shown when methane decomposition took place at a lower reaction temperature such as 823 K. XRD studies suggested that iron atoms had entered into the Ni lattice and Ni–Fe alloy was formed in Ni–Fe–SiO₂ catalysts. The structure of the carbon filaments generated over Ni–SiO₂ and Ni–Fe–SiO₂ was quite different. TEM studies showed that “multi-walled” carbon filaments were formed over 75%Ni–25%SiO₂ catalyst, while “bamboo-shaped” carbon filaments generated over 35%Ni–40%Fe–25%SiO₂ catalysts at 923 K. Raman spectra of the generated carbons demonstrated that the graphitic order of the “multi-walled” carbon filaments was lower than that of the “bamboo-shaped” carbon filaments.     

Effect of copper loading on copper-ceria catalysts performance in CO selective oxidation for fuel cell applications

Copper–ceria catalysts with three different Cu loadings (1, 7 and 15 wt%) were prepared by incipient wet impregnation, dried at 120 °C and calcined in air at 500 °C. The as-prepared catalysts were characterized by XRD, BET, Diffuse Reflectance Spectroscopy (DRS–UV–visible), Raman spectroscopy, CO and H₂-TPR, CO-TPR, CO-TPD and Oxygen Storage Capacity (OSC) measurements (with CO and O₂ concentration step-changes). The results indicated a good dispersion of copper for catalysts with 1 and 7 wt% Cu; however, bulk CuO was present for catalyst with 15 wt% Cu loading. Catalyst with 7 wt% Cu was observed to have very high capacity to release lattice oxygen to oxidize CO at low temperature. Activity results for CO oxidation in the absence and in the presence of 60% H₂, demonstrated a very similar performance for catalysts with 7 and 15 wt% Cu (both with T₁₀₀ = 112 °C), and much better than that of catalyst loaded with 1 wt% Cu. Catalyst with 7 wt% of copper shows very high activity (100% in a wide temperature window) and selectivity (higher than 85%), which makes an attractive for its use in purification of hydrogen for fuel cell applications. The presence of a mixture of CO₂ and H₂O inhibited catalyst activity, with CuO/CeO₂ catalyst with 7 wt% Cu exhibiting the best performance in the overall reaction temperature range. This could be attributed to the presence of highly disperse copper, only part of it in deep interaction with ceria. The effect of O₂/CO ratio (λ) and the potential reversibility of the inhibitory effect of CO₂ and H₂O were also investigated.     

High-performance cobalt–tungsten–boron catalyst supported on Ni foam for hydrogen generation from alkaline sodium borohydride solution

Low cost and catalytically effective transition metal catalysts are highly wanted in developing on-demand hydrogen generation system for practical onboard application. By using a modified electroless plating method, we have prepared a robust Co–W–B amorphous catalyst supported on Ni foam (Co–W–B/Ni foam catalyst) that is highly effective for catalyzing hydrogen generation from alkaline NaBH₄ solution. It was found that the plating times, calcination temperature, NaBH₄ and NaOH concentrations all exert considerable influence on the catalytic effectiveness of Co–W–B/Ni foam catalyst towards the hydrolysis reaction of NaBH₄. Via optimizing these preparation and reaction conditions, a hydrogen generation rate of 15 L/min g (Co–W–B) has been achieved, which is comparable to the highest level of noble metal catalyst. In consistent with the observed pronounced catalytic activity, the activation energy of the hydrolysis reaction using Co–W–B/Ni foam catalyst was determined to be only 29 kJ/mol. Based on the phase analysis and structural characterization results, the mechanism underlying the observed dependence of catalytic effectiveness on the calcination temperature was discussed.     

Ni/CeO2/ZSM-5 catalysts for the production of hydrogen from the pyrolysis–gasification of polypropylene

The production of hydrogen from the two-stage pyrolysis–gasification of polypropylene using a Ni/CeO₂/ZSM-5 catalyst has been investigated. Experiments were conducted on CeO₂ loading, calcination temperature and Ni loading of the Ni/CeO₂/ZSM-5 catalyst in relation to hydrogen production. The results indicated that with increasing CeO₂ loading from 5 to 30 wt.% for the 10 wt.% Ni/CeO₂/ZSM-5 catalyst calcined at 750 °C, hydrogen concentration in the gas product and the theoretical potential hydrogen production were decreased from 63.0 to 49.8 vol.% and 50.4 to 21.6 wt.%, respectively. In addition, the amount of coke deposited on the catalyst was reduced from 9.5 to 6.2 wt.%. The calcination temperature had little influence on hydrogen production for the catalyst containing 5 wt.% of CeO₂. However, for the 10 wt.% Ni/CeO₂/ZSM-5 catalyst with a CeO₂ content of 10 or 30 wt.%, the catalytic activities reduced when the calcination temperature was increased from 500 to 750 °C. The SEM results showed that large amounts of filamentous carbons were formed on the surface of the catalysts. The investigation of different Ni content indicates that the Ni/CeO₂/ZSM-5 ((2-10)-5-500) catalyst containing 2 wt.% Ni showed poor catalytic activity in relation to the pyrolysis–gasification of polypropylene according to the theoretical potential H₂ production (7.2 wt.%). Increasing the Ni loading to 5 or 10 wt.% in the Ni/CeO₂/ZSM-5 ((2-10)-5-500) catalyst, high potential hydrogen production was obtained.     

Production of hydrogen and nanofibrous carbon by selective catalytic decomposition of propane

The process of production of highly concentrated CO_x-free hydrogen and nanofibrous carbon (NFC) by catalytic propane decomposition on Ni and Ni–Cu catalysts (different in active phase composition) at relatively low temperatures (400–700 °C) was investigated. The bimetallic Ni–Cu catalysts showed significantly higher propane conversion and longer lifetime than monometallic Ni catalyst. The Ni (50 wt.%)–Cu (40 wt.%)/SiO₂ catalyst exhibited the best activity and selectivity at 600 °C. Total hydrogen yield of 60.8 mol H₂/g_cat (during 24 h time on stream) and the total H₂:CH₄ ratio of 8.4 were obtained during propane decomposition under these optimal conditions. The possible reaction scheme of propane decomposition over Ni-based catalysts and the reasons of increasing the selectivity of hydrogen are discussed.     

Steam reforming of ethanol over copper-zirconia based catalysts doped with Mn,Ni, Ga

The activity toward hydrogen production in steam reforming of ethanol (SRE) reaction has been evaluated for CuO/ZrO₂ catalysts doped with Mn, Ni, Ga at 350 °C. The copper based catalysts were synthesised by co-precipitation method at constant pH = 7 and fixed (wt.%) CuO/ZrO = 2.3. The catalysts were characterised by means of N₂ adsorption, temperature programmed reduction (H₂-TPR), N₂O dissociative chemisorption, X-ray diffraction (XRD), CO₂ temperature programmed desorption (CO₂-TPD), and temperature programmed oxidation (TPO). It has been found that copper based catalysts exhibit high ethanol conversion in SRE (>86%) at 350 °C. Due to basic character of catalysts, the formation of acetaldehyde is observed. The CuO/ZrO₂ catalyst modification with dopants increases the hydrogen yield with maximum (52%) for CuO/ZrO₂/NiO. The addition of Ni changes the distribution of carbon-containing products. In this case, the increase in selectivity to CO, CO₂ and CH₄ is observed whereas selectivity to acetaldehyde is significantly decreased. This shows that presence of Ni facilities the C–C bond cleavage. On the other hand, the formation of acetic acid is limited upon addition of Mn and Ga. For all modified catalysts, decrease in carbon deposition rate during SRE is pronounced according to TPO experiments. The modification of Cu/Zr with Mn, Ni and Ga causes the decrease in copper particle size, which hinders the carbon deposit formation.     

Catalytic steam reforming of acetic acid in a fluidized bed reactor with oxygen addition

Catalytic steam reforming of bio-oil is a promising process for producing hydrogen in a sustainable environmentally friendly way that can improve the utilization of local resources (natural sources or wastes). However, there remain drawbacks such as coke formation that produce operational problems and deactivation of the catalysts. Coprecipitated Ni/Al catalysts are here used in a fluidized bed for reforming at 650 °C of acetic acid as a model compound of bio-oil–aqueous fraction. Different strategies are applied in order to study their effects on the catalytic steam reforming process: modification of the catalyst by increasing the calcination temperature or adding promoters such as calcium. The addition of small quantities of oxygen is also tested resulting in an optimum percentage to achieve a high carbon conversion process with less coke and without a hydrogen yield penalty production. The results for catalytic steam reforming are compared with other ones from literature.     

Biogas dry reforming over Ni-Al catalyst: Suppression of carbon deposition by catalyst preparation and activation

Biogas dry reforming is as an alternative renewable route for the hydrogen production. However, the major drawback of this process is the catalyst deactivation by carbon deposition and sintering. In this work, Ni-Al catalysts were studied aiming to suppress the carbon deposition in the dry reforming of biogas. The catalysts were prepared by coprecipitation and evaluated the washing step. The reactions were carried out with unreduced and reduced catalysts in a fixed bed tubular reactor using a synthetic biogas (60% CH₄ and 40% CO₂). The washing and activation steps influenced the characteristics of the catalysts and the catalytic properties in the biogas reforming. The unwashed sample resulted in an oxide containing potassium nickelate with high basicity and low surface area. Both washed samples, reduced and unreduced, showed a high amount of carbon formation, whereas no carbon formation was observed in the unwashed samples for the reactions in the temperature range of 500–750 °C. The unwashed and unreduced sample was the only one that maintained the activity during all the reaction time at 700 °C (40% CH₄ conversion and 75% CO₂ conversion), low coke amount and no evidence of sintering, which was confirmed by XRD, TPO, and SEM analyses. The carbon suppression was related to the nickelate phase and to the Ni carbide formation in the unwashed and unreduced catalyst. In summary, the carbon deposition in biogas dry reforming was completely controlled between 600 and 750 °C using the unwashed and unreduced Ni-Al catalyst.     

Oleic acid gasification over supported metal catalysts in supercritical water: Hydrogen production and product distribution

Oleic acid was examined as a model compound for lipids, which was gasified in supercritical water (SCW) using a batch reactor from 400 to 500 °C at 28 MPa. The influence of operating temperature and several commercial catalysts on the gasification efficiency, hydrogen gas yield, and residual liquid product quality was examined and discussed. The main gaseous components measured were carbon dioxide (CO₂), hydrogen (H₂), methane (CH₄), and traces of carbon monoxide (CO). The residual liquid after reaction was characterized by analyzing the chemical oxygen demand (COD), total organic carbon (TOC), volatile fatty acids (VFAs), and the long chain fatty acids (LCFAs), namely, palmitic, myristic, stearic, linoleic, and oleic acids. The results showed that an increase of temperature coupled with the use of catalyst enhanced the gas yield dramatically. The H₂ yield was 15 mol/mol oleic acid converted using both the pelletized Ru/Al₂O₃ and powder Ni/Silica-alumina catalysts which gave 4 times higher than the equilibrium yield. The COD reduction efficiency ranged from 31% at 400 °C without catalyst to 96 % at 500 °C in the presence of Ni/Silica-alumina catalyst. The composition of residual liquid products was studied using gas chromatography/mass spectrometry (GC-MS), with a generalized reaction pathway for oleic acid decomposition in SCW reported.     

Experimental study of Ni/CeO2 catalytic properties and performance for hydrogen production in sulfur–iodine cycle

The Ni/CeO₂ catalysts with different calcination temperatures have been tested for hydrogen production in sulfur–iodine (SI or IS) cycle. TG-FTIR, BET, XRD, HRTEM and TPR were performed for catalyst characterization. It was found that the Ni²⁺ ions could be inserted into the ceria lattice. This brought about the strong interaction between Ni and CeO₂ and the generation of oxygen vacancies. Perfect crystallites were formed in the catalysts. It was evident that there was a change in particle size and morphology as the calcination temperature increased from 300 to 900 °C. The Ni/CeO₂ catalysts with different calcination temperatures showed better catalytic activity by comparison with blank yield, especially Ni/Ce700. A hypothetic mechanism of HI catalytic decomposition on Ni/CeO₂ has been constructed. The two important reactive sites were assumed for HI catalytic decomposition.     

Ni–Cu–Zn/MCM-22 catalysts for simultaneous production of hydrogen and multiwall carbon nanotubes via thermo-catalytic decomposition of methane

Pure hydrogen and carbon nanotubes were produced via thermo-catalytic decomposition (TCD) of methane over Ni-loaded MCM-22 catalysts in a vertical fixed-bed reactor. The effect of reaction temperature, gas hourly space velocity (GHSV), Cu/Zn promoter and time on stream on the methane conversion, hydrogen and carbon yields were studied over the synthesized catalysts. The catalytic performance of the 50%Ni–5%Cu–5%Zn/MCM-22 catalyst was found to be highly stable compared to other catalysts. The highest conversion of methane over 50%Ni–5%Cu–5%Zn/MCM-22 catalyst reached 85% with 947% carbon yield. Methane conversion increased on increasing the reaction temperature up to 750 °C and decreased thereafter at higher temperatures. XRD and TEM analysis of the carbon byproduct revealed that graphitic carbon appeared as a major crystalline phase during the reaction. HRTEM results revealed that most of the Ni particles were located on the tip of the carbon nanofibers/nanotubes formed on the spent catalysts. The carbon nanofibres have an average outer diameter of approximately 20–40 nm with an average length of 450–500 nm. Four types of carbon nanofibers were detected and their formation strongly depended on the reaction temperature, time on stream and degree of the interaction between the metallic Ni particle and support. The optimum conditions for CNT production within the experimental ranges were found at a reaction temperature of 750 °C.     

Carbon-supported cobalt catalyst for hydrogen generation from alkaline sodium borohydride solution

Low cost transition metal catalysts with high performance are attractive for the development of on-board hydrogen generation systems by catalytic hydrolysis of sodium borohydride (NaBH₄) in fuel cell fields. In this study, hydrogen production from alkaline NaBH₄ via hydrolysis process over carbon-supported cobalt catalysts was studied. The catalytic activity of the supported cobalt catalyst was found to be highly dependent on the calcination temperatures. The hydrogen generation rate increases with calcination temperatures in the range of 200–400 °C, but a high calcination temperature above 500 °C led to markedly decreased activity. X-ray diffraction patterns reveal that the catalysts experience phase transition from amorphous Co–B to crystalline cobalt hydroxide with increase in calcination temperatures. The reaction performance is also dependent on the concentration of NaBH₄, and the hydrogen generation rate increases for lower NaBH₄ concentrations and decreases after reaching a maximum at 10 wt.% of NaBH₄.     

Hydrogen production by auto-thermal reforming of ethanol over nickel catalyst supported on mesoporous yttria-stabilized zirconia

Mesoporous yttria-stabilized zirconia (YSZ-X) supports with different Y/Zr molar ratio (X) were prepared by a sol–gel method. 20 wt% Ni catalysts supported on YSZ-X (X = 0, 0.1, 0.2, and 0.3) were then prepared by an incipient wetness impregnation method for use in hydrogen production by auto-thermal reforming of ethanol. The effect of Y/Zr molar ratio (X) on the catalytic performance of Ni/YSZ-X (X = 0, 0.1, 0.2, and 0.3) catalysts was investigated. Hydrogen selectivity and by-product distributions over the catalysts were different depending on the Y/Zr molar ratio (X). Hydrogen selectivity over Ni/YSZ-X (X = 0, 0.1, 0.2, and 0.3) catalysts showed a volcano-shaped curve with respect to Y/Zr molar ratio (X). Among the catalysts tested, Ni/YSZ-0.1 showed the best catalytic performance and the lowest carbon deposition in hydrogen production by auto-thermal reforming of ethanol. High reducibility and excellent structural stability of Ni/YSZ-0.1 catalyst were responsible for its superior catalytic performance.     

High temperature iron-based catalysts for hydrogen and nanostructured carbon production by methane decomposition

The production of hydrogen and filamentous carbon by means of methane decomposition was investigated in a fixed-bed reactor using iron-based catalysts. The effect of the textural promoter and the addition of Mo as a dopant affects the catalysts performance substantially: iron catalyst prepared with Al₂O₃ showed slightly higher catalytic performance as compared to those prepared with MgO; Mo addition was found to improve the catalytic performance of the catalyst prepared with MgO, whereas in the catalyst prepared with Al₂O₃ displayed similar or slightly poorer results. Additionally, the influence of the catalyst reduction temperature, the reaction temperature and the space velocity on the hydrogen yield was thoroughly investigated. The study reveals that iron catalysts allow achieving high methane conversions at operating temperatures higher than 800 °C, yielding simultaneously carbon nanofilaments with interesting properties. Thus, at 900 °C reaction temperature and 1 l g⁻¹_cat h⁻¹ space velocity, ca. 93 vol% hydrogen concentration was obtained, which corresponds to a methane conversion of 87%. Additionally, it was found that at temperatures higher than 700 °C, carbon co-product is deposited mainly as multi walled carbon nanotubes. The textural and structural properties of the carbonaceous structures obtained are also presented.     

Direct borohydride fuel cell using Ni-based composite anodes

In this study, nickel-based composite anode catalysts consisting of Ni with either Pd on carbon or Pt on carbon (the ratio of Ni:Pd or Ni:Pt being 25:1) were prepared for use in direct borohydride fuel cells (DBFCs). Cathode catalysts used were 1 mg cm⁻² Pt/C or Pd electrodeposited on activated carbon cloth. The oxidants were oxygen, oxygen in air, or acidified hydrogen peroxide. Alkaline solution of sodium borohydride was used as fuel in the cell. High power performance has been achieved by DBFC using non-precious metal, Ni-based composite anodes with relatively low anodic loading (e.g., 270 mW cm⁻² for NaBH₄/O₂ fuel cell at 60 °C, 665 mW cm⁻² for NaBH₄/H₂O₂ fuel cell at 60 °C). Effects of temperature, oxidant, and anode catalyst loading on the DBFC performance were investigated. The cell was operated for about 100 h and its performance stability was recorded.     

Effect of SiO2-ZrO2 supports prepared by a grafting method on hydrogen production by steam reforming of liquefied natural gas over Ni/SiO2-ZrO2 catalysts

SiO₂-ZrO₂ supports with various zirconium contents are prepared by grafting a zirconium precursor onto the surface of commercial Carbosil silica. Ni(20 wt.%)/SiO₂-ZrO₂ catalysts are then prepared by an impregnation method, and are applied to hydrogen production by steam reforming of liquefied natural gas (LNG). The effect of SiO₂-ZrO₂ supports on the performance of the Ni(20 wt.%)/SiO₂-ZrO₂ catalysts is investigated. SiO₂-ZrO₂ prepared by a grafting method serves as an efficient support for the nickel catalyst in the steam reforming of LNG. Zirconia enhances the resistance of silica to steam significantly and increases the interaction between nickel and the support, and furthermore, prevents the growth of nickel oxide species during the calcination process through the formation of a ZrO₂-SiO₂ composite structure. The crystalline structures and catalytic activities of the Ni(20 wt.%)/SiO₂-ZrO₂ catalysts are strongly influenced by the amount of zirconium grafted. The conversion of LNG and the yield of hydrogen show volcano-shaped curves with respect to zirconium content. Among the catalysts tested, the Ni(20 wt.%)/SiO₂-ZrO₂ (Zr/Si = 0.54) sample shows the best catalytic performance in terms of both LNG conversion and hydrogen yield. The well-developed and pure tetragonal phase of ZrO₂-SiO₂ (Zr/Si = 0.54) appears to play an important role in the adsorption of steam and subsequent spillover of steam from the support to the active nickel. The small particle size of the metallic nickel in the Ni(20 wt.%)/SiO₂-ZrO₂ (Zr/Si = 0.54) catalyst is also responsible for its high performance.     

Continuous liquid-phase valorization of bio-ethanol towards bio-butanol over metal modified alumina

Commercial mixed-phase aluminum oxide was used as a heterogeneous catalyst support, providing slightly basic properties which are well-suited for the condensation of bio-ethanol to C₄ hydrocarbons, such as 1-butanol. Different metals (Cu, Ni and Co), at various metal loadings were deposited on the support. Consequently, the catalytic reactions were carried out in a continuous laboratory-scale fixed bed reactor operated at 240 °C and 70 bar. The catalysts were characterized by means of XRD, TEM, FT-IR, XPS and ICP-OES. Different metals were found to give entirely different product distributions. With the best catalysts, the selectivities towards 1-butanol close to 70% were reached, while the ethanol conversion typically varied between 10 and 30% – strongly depending on the metal applied. It was observed that low loading of copper and high loading of nickel were responsible for the formation of 1-butanol, whereas cobalt and high loading of copper resulted in the production of ethyl acetate. The reaction was found to be extremely sensitive to catalyst preparation conditions and procedures such as metal loading, calcination/reduction temperature and, thereby, to the formation of corresponding crystallite structure.