Surface/structure functionalization of copper-based catalysts by metal-support and/or metal–metal interactions

Konsolakis, Michalis; Ioakeimidis, Zisis

doi:10.1016/j.apsusc.2014.08.114

Cited by 49 publications

(33 citation statements)

References 93 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The spectrum of the Cu/CeO 2 sample is characterized by a Cu 2p 3/2 band at 933.8 eV and shake-up satellites at ca. 944.0 eV, typical characteristics of Cu 2+ species in CuO-like phase [20,48,[66][67][68][69][70]. The above assignments are in line with the XRD findings, which revealed the formation of the corresponding metal oxides in M/CeO 2 samples (Table 2).…”

Section: Surface Characterization (Xps Analysis)supporting

confidence: 76%

“…Under these perspectives, several catalytic systems, involving mainly base (e.g., Ni, Co, Cu) and precious (e.g., Pt, Rh, Ru, Pd, and Ir) metal supported catalysts have been reported for ESR [10,12]. Although the noble metal-based catalysts demonstrate sufficient reforming activity in a wide temperature range [10,12,[14][15][16][17][18][19], their large-scale implementation in practice is limited by their significant high cost [20]. Hence, the development of active and stable non-precious metal catalysts for ESR is highly desirable.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

et al. 2016

Self Cite

View full text Add to dashboard Cite

Abstract:The aim of the present work was to investigate steam reforming of ethanol with regard to H 2 production over transition metal catalysts supported on CeO 2 . Various parameters concerning the effect of temperature (400-800˝C), steam-to-carbon (S/C) feed ratio (0.5, 1.5, 3, 6), metal entity (Fe, Co, Ni, Cu) and metal loading (15-30 wt.%) on the catalytic performance, were thoroughly studied. The optimal performance was obtained for the 20 wt.% Co/CeO 2 catalyst, achieving a H 2 yield of up to 66% at 400˝C. In addition, the Co/CeO 2 catalyst demonstrated excellent stability performance in the whole examined temperature range of 400-800˝C. In contrast, a notable stability degradation, especially at low temperatures, was observed for Ni-, Cu-, and Fe-based catalysts, ascribed mainly to carbon deposition. An extensive characterization study, involving N 2 adsorption-desorption (BET), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM/EDS), X-ray Photoelectron Spectroscopy (XPS), and Temperature Programmed Reduction (H 2 -TPR) was undertaken to gain insight into the structure-activity correlation. The excellent reforming performance of Co/CeO 2 catalysts could be attributed to their intrinsic reactivity towards ethanol reforming in combination to their high surface oxygen concentration, which hinders the deposition of carbonaceous species.

show abstract

Section: Surface Characterization (Xps Analysis)supporting

confidence: 76%

Section: Introductionmentioning

confidence: 99%

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…This result is in agreement with the literature which reported that a Cu/ CeO 2 catalyst has higher reducibility than Cu/La 2 O 3 which can be seen on the reduction peak of CuO at 150-280°C and 200-350°C for Cu/CeO 2 and Cu/La 2 O 3 catalysts, respectively. 45 The similar position of the reduction peak of NiO with Ce substitution is due to the fact that the perovskite structure can still be formed as shown in the XRD results, indicating that while Ni interacts with Cu to form bimetallic Ni-Cu particles, Ni has also a strong interaction with La while Cu has a strong interaction with Ce.…”

Section: Reduction Profile (Tpr) Of Fresh Catalystsmentioning

confidence: 70%

Sulfur resistant La_xCe_1−xNi_0.5Cu_0.5O₃ catalysts for an ultra-high temperature water gas shift reaction

Oemar

Bian

Hidajat

et al. 2016

Catal. Sci. Technol.

View full text Add to dashboard Cite

A series of La x Ce 1−x Ni 0.5 Cu 0.5 O 3 catalysts was synthesized to study the effect of Ce substitution for La. XRD results show that only a small amount of Ce (10%) is allowable to substitute La to maintain the perovskite structure. The La 0.9 Ce 0.1 Ni 0.5 Cu 0.5 O 3 catalyst has the smallest metal particle size and the highest oxygen mobility among all tested catalysts as observed from the XRD, TPD-O 2 , and XPS results of reduced catalysts. These two factors are very important in achieving the highest catalytic activity of the La 0.9 Ce 0.1 Ni 0.5 Cu 0.5 O 3 catalyst in a water gas shift reaction at 450-650°C. In the presence of H 2 S, the catalytic activity at lower temperature was suppressed due to the formation of stable SO 4 2− species on the metal. However, since the amounts of surface oxygen species and adsorbed H 2 S are much lower at high temperature, the formation of SO 4 2− species is not observed, resulting in higher catalytic activity. The presence of H 2 S at high temperature enhances the formation of formate species, which can decompose to produce methane as the side product of the water gas shift reaction. IntroductionThe Water Gas Shift (WGS) reaction is one of the key reactions for hydrogen production in industry. The reaction is favorable at a low reaction temperature due to exothermicity. However, the reaction rate is lower at lower temperatures. Hence, the WGS reaction is industrially performed in two stages, i.e. high temperature WGS at 350-450°C to increase the reaction rate using an Fe-Cr catalyst, followed by low temperature WGS at 200-250°C to convert the remaining CO in the system using a Cu-Zn catalyst. With current growing interest in hydrogen production via biomass gasification technology which produces sulfur containing syngas, it is important to develop a new catalyst having high activity and stability not only at low (200-250°C) and high temperature (350-450°C) WGS reactions but also at ultra high temperatures (500-650°C) in the presence of a wide range of sulfur concentration. It is understood that biomass gasification is usually performed at high temperatures of 700-900°C. The syngas produced from the biomass gasification has a temperature of 700°C while the conventional WGS reaction requires lower reaction temperatures (200-450°C ). Hence, the syngas needs cooling for the reaction to take place, which means energy loss. The ultra high temperature WGS reaction can minimize the energy loss due to cooling of syngas. The consequences of having a sulphur resistant WGS catalyst is that the downstream hydrogen separation process should have sulphur resistant properties as well. Hence, there is growing interest in sulphur resistant H 2 separation membranes. 1 Various types of sulfur-resistant catalysts have been reported in the literature, such as W-based catalysts, 2,3 Mobased catalysts 4-7 lanthanide oxysulfide La 2 O 2 S, 8,9 noble metal catalysts (Rh,10,(11)(12)(13)), and phosphide catalysts. 14 Sulphided CoMo catalysts in promoted and unpromoted systems have been extensively...

show abstract

“…CoCe-MA As shown in Figure 6, three reduction peaks were observed in the temperature range of 50-900 • C. According to the literature [39,41], the first reduction peak (P H2 -I) was attributed to the reduction of Co 3 O 4 to CoO, while the second peak (P H2 -II) was due to the further reduction of CoO to metallic cobalt [42]. In addition, the weak reduction peaks around 480 • C (P H2 -III) could be ascribed to the reduction of surface oxygen species of CeO 2 [43,44]. As listed in Table 5, the peak area ratios of P H2 -II/P H2 -I were in the range of 2.90−3.07, which was close to the theoretical values (the theoretical H 2 consumption ratio of P H2 -II/P H2 -I should be 3:1).…”

Section: Ph2-i Ph2-ii Ph2-iii Total Ratio Of Ph2-ii /Ph2-i T50 (°C) Tmentioning

confidence: 89%

Effect of Small Molecular Organic Acids on the Structure and Catalytic Performance of Sol–Gel Prepared Cobalt Cerium Oxides towards Toluene Combustion

et al. 2019

View full text Add to dashboard Cite

Cobalt cerium oxide catalysts with small molecular organic acids (SOAs) as chelating agents were prepared via the sol–gel method and investigated for the complete oxidation of toluene. Four kinds of natural SOAs, i.e. malic acid (MA), citric acid (CA), glycolic acid (GA), and tartaric acid (TA), were selected. The effect of organic acids on the composition, structure, morphology and catalytic performance of metal oxides is discussed in details. The cobalt cerium oxides catalysts were characterized by various techniques, including TG–DSC, XRD, SEM–EDS, N2–adsorption and desorption, XPS, and H2–TPR analyses. The results show that the nature of organic acids influenced the hydrolysis, condensation and calcination processes, as well as strongly affected the textural and physicochemical properties of the metal oxides synthesized. The best catalytic activity was obtained with the CoCe–MA catalyst, and the toluene conversion reached 90% at 242 °C. This outstanding catalytic activity could be related to its textural, redox properties and unique surface compositions and oxidation states. In addition, the CoCe–MA catalyst also showed excellent stability in long–time activity test.

show abstract

Surface/structure functionalization of copper-based catalysts by metal-support and/or metal–metal interactions

Cited by 49 publications

References 93 publications

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

Sulfur resistant La_xCe_1−xNi_0.5Cu_0.5O₃ catalysts for an ultra-high temperature water gas shift reaction

Effect of Small Molecular Organic Acids on the Structure and Catalytic Performance of Sol–Gel Prepared Cobalt Cerium Oxides towards Toluene Combustion

Contact Info

Product

Resources

About

Surface/structure functionalization of copper-based catalysts by metal-support and/or metal–metal interactions

Cited by 49 publications

References 93 publications

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

Sulfur resistant LaxCe1−xNi0.5Cu0.5O3 catalysts for an ultra-high temperature water gas shift reaction

Effect of Small Molecular Organic Acids on the Structure and Catalytic Performance of Sol–Gel Prepared Cobalt Cerium Oxides towards Toluene Combustion

Contact Info

Product

Resources

About

Sulfur resistant La_xCe_1−xNi_0.5Cu_0.5O₃ catalysts for an ultra-high temperature water gas shift reaction