Maria Goula - Academia.edu (original) (raw)
Papers by Maria Goula
Reaction Chemistry and Engineering, 2022
Climate change, greenhouse effect and fossil fuel extraction have gained a growing interest in re... more Climate change, greenhouse effect and fossil fuel extraction have gained a growing interest in research and industrial circles to provide alternative chemicals and fuel synthesis technologies. Carbon dioxide (CO2) hydrogenation to value-added chemicals using hydrogen (H2) from renewable power (solar, wind) offers a unique solution. From this aspect this review describes the various products, namely methane (C1), methanol, ethanol, dimethyl ether (DME) and hydrocarbons (HCs) originating via CO2 hydrogenation reaction. In addition, conventional reactor units for the CO2 hydrogenation process are explained, as well as different types of microreactors with key pathways to determine catalyst activity and selectivity of the value-added chemicals. Finally, limitations between conventional units and microreactors and future directions for CO2 hydrogenation are detailed and discussed. The benefits of such setups in providing platforms that could be utilized in the future for major scale-up and industrial operation are also emphasized.
Bimetallic Exsolved Heterostructures of Controlled Composition with Tunable Catalytic Properties
ACS Nano
Towards maximizing conversion of ethane and carbon dioxide into synthesis gas using highly stable Ni-perovskite catalysts
Journal of CO2 Utilization
Sustainability, 2022
The paper explores the potential for adaptive mitigation at the Montezuma Wildlife Refuge, Seneca... more The paper explores the potential for adaptive mitigation at the Montezuma Wildlife Refuge, Seneca Falls, NY, USA, and surrounds, focusing on landscapes along the historic Erie Canal that inadvertently lowered the water table and shrunk adjacent wetlands. Now the Erie Canal National Heritage Corridor (ECNHC), Montezuma, NY, USA, the canal, and surrounds lack a clear identity but have the potential to be repurposed as green infrastructure to support climate mitigation through the application of natural climate solutions, namely reforestation. Reforestation has been shown to produce the highest potential performance for carbon sequestration, along with a multitude of co-benefits. However, most studies assessing capacity for climate mitigation using nature-based approaches operate at a high level via remote data and do not test hypotheses at smaller scales that require groundtruthing data, parcel-by parcel approaches, and an understanding of landowner values. The initial research questi...
Ni/CNT/Zeolite-Y composite catalyst for efficient heptane hydrocracking: Steady-state and transient kinetic studies
Applied Catalysis A: General, 2022
Ir/Al2O3触媒上の亜酸化窒素低減に対するアルカリ助触媒(K)の効果
Topics in Catalysis, 2016
Journal of Environmental Chemical Engineering, 2016
The impact of H 2 as additional reducing agent on the SCR of NO with C 3 H 6 in excess oxygen, wa... more The impact of H 2 as additional reducing agent on the SCR of NO with C 3 H 6 in excess oxygen, was comparatively explored over low noble metal loading (0.5 wt%), Pt/g-Al 2 O 3 , Pd/g-Al 2 O 3 , Ir/g-Al 2 O 3 catalysts. To gain insight into the role of H 2 , the reactions NO + C 3 H 6 + O 2 (R#1), NO + C 3 H 6 + O 2 + H 2 (R#2), NO + H 2 + O 2 (R#3) were employed. In respect to propene oxidation, the Pd > Pt > Ir sequence was obtained under R#1, since they exhibit complete conversion at 220, 250, 325 C, respectively; all metals exhibit moderate deNOx performances (X NO, <40%). H 2 co-presence (R#2) promotes both the NO and C 3 H 6 conversions, which is valid in the whole temperature interval investigated (50-400 C), being more substantial for Pt/g-Al 2 O 3 and Ir/g-Al 2 O 3 , less beneficial for Pd/g-Al 2 O 3. A two-maxima feature is obtained on X NO pattern (at 100and100 and 100and230 C) of Pt and Pd during R#2. The low temperature maximum Àattributed to NO reduction by H 2-is substantially more pronounced on Pt than Pd, offering X NO 9090% and S N2 9085%; the high temperature maximum-attributed to NO reduction by C 3 H 6-is higher by $15% on both Pt and Pd, in respect to the values obtained during R#1, while S N2 remained unaffected. Different X NO pattern with one maximum is obtained over Ir, implying a synergistic interaction between H 2 and C 3 H 6. This synergy is accompanied by a substantial widening of the NO reduction window toward lower temperatures and a considerable increase on both X NO,max and S N2
Topics in Catalysis, 2016
The promoting impact of potassium (0-1 wt. % K) on nitrous oxide (N 2 O) catalytic decomposition ... more The promoting impact of potassium (0-1 wt. % K) on nitrous oxide (N 2 O) catalytic decomposition over Ir/Al 2 O 3 is investigated under both oxygen deficient and oxygen excess conditions. All samples were characterized by means of X-ray powder diffraction (XRD), temperature-programmed reduction (H 2-TPR), ammonia desorption (NH 3-TPD) and Fourier Transform Infrared Spectroscopy of pyridine adsorption (FTIR-Pyridine). The results reveal that the K-free Ir/Al 2 O 3 catalyst consists mainly of the IrO 2 phase, exhibiting also significant Lewis acidity, which is gradually eliminated by the addition of K. Catalytic performance results showed that the deN 2 O performance in the absence of O 2 in the feed mixture is negatively affected upon increasing potassium loading. However, under oxygen excess conditions, a pronounced effect of K is observed. Although the catalytic performance of the un-doped catalyst is drastically hindered by the presence of O 2 , the K-promotion notably prohibits the oxygen poisoning. The optimum deN 2 O performance is obtained with potassium loading of 0.5 wt. % K, which offers complete conversion of N 2 O at 580 ο C, instead of the corresponding 50% N 2 O conversion achieved with the unmodified sample.
Hydrogen Production via Glycerol Steam Reforming over Ni/Al2O3: Influence of Nickel Precursors
ACS Sustainable Chemistry & Engineering, 2013
Applied Catalysis B: Environmental, 2012
In this work the activity of Ni catalysts in hydrogen production by glycerol steam reforming was ... more In this work the activity of Ni catalysts in hydrogen production by glycerol steam reforming was studied. Moreover the effect of the support (TiO 2 , SBA-15 and ZrO 2) on the catalytic performance of Ni was evaluated. A strong effect of the support on the activity of the samples was detected. The Ni/TiO 2 sample showed negligible activity mainly due to the low strength of anatase to keep nickel in the reduced state. In fact, both incorporation of Ni ions into the nanoanatase lattice and oxidation of the active phase to NiO under operating conditions were observed. A deactivation process was also found with the Ni/SBA-15 sample while the best results were achieved with the Ni/ZrO 2 catalyst, showing no deactivation. After 20 hours, the glycerol conversion was 72% and the H 2 yield was 65%. The Ni/ZrO 2 sample was even more active when tested at lower temperatures, although its performance was less stable. On the basis of the experimental results, it was evidenced that the nature of the support affects above all the stability of the active phase. In particular, strong interactions between the metal active phase and the support ensures stability, activity and selectivity of the catalyst in glycerol steam reforming reactions.
Global NEST International Conference on Environmental Science & Technology
Here we report on the effect of the support and preparation method on the activity and stability ... more Here we report on the effect of the support and preparation method on the activity and stability of Ir-based catalysts under CO oxidation. Alunina-ceria-zirconia (ACZ: 60wt%Al2O3 - 40wt%CexZr1-xO2, x=0.25, 0.5, 0.75) mixed oxide supports with high oxygen storage capacity (OSC) were synthesized via two different methods, hydrothermal (ACZ-H) and co-precipitation (ACZ-P), and used as supports of Ir nanoparticles, so as, besides the Ce/Zr composition to also deal with the effect of the preparation method on catalytic performance. ACZ supports and counterpart Ir/ACZ catalysts were thoroughly characterized using various techniques, while catalytic measurements were conducted under excess O2 conditions (1.0% CO, 5.0% O2, balance He at 1 bar) in the temperature range of 100-400oC. Both pre-reduced and pre-oxidized catalysts were evaluated, while their sintering behavior after experiencing several sequential oxidative thermal aging steps was also studied. The results demonstrated superior t...
Nanomaterials
The catalytic oxidation of CO is probably the most investigated reaction in the literature, for d... more The catalytic oxidation of CO is probably the most investigated reaction in the literature, for decades, because of its extended environmental and fundamental importance. In this paper, the oxidation of CO on La1−xSrxMnO3 perovskites (LSMx), either unloaded or loaded with dispersed Ir nanoparticles (Ir/LSMx), was studied in the temperature range 100–450 °C under excess O2 conditions (1% CO + 5% O2). The perovskites, of the type La1−xSrxMnO3 (x = 0.0, 0.3, 0.5 and 0.7), were prepared by the coprecipitation method. The physicochemical and structural properties of both the LSMx and the homologous Ir/LSMx catalysts were evaluated by various techniques (XRD, N2 sorption–desorption by BET-BJH, H2-TPR and H2-Chem), in order to better understand the structure–activity–stability correlations. The effect of preoxidation/prereduction/aging of the catalysts on their activity and stability was also investigated. Results revealed that both LSMx and Ir/LSMx are effective for CO oxidation, with the...
Toward Maximizing the Selectivity of Diesel-Like Hydrocarbons from Oleic Acid Hydrodeoxygenation Using Ni/Co-Al2o3 Embedded Mesoporous Silica Nanocomposite Catalysts: An Experimental and Dft Approach
CO2 hydrogenation for the production of higher alcohols: Trends in catalyst developments, challenges and opportunities
Catalysis Today
Biogas dry reforming over Ni/LnOx-type catalysts (Ln = La, Ce, Sm or Pr)
International Journal of Hydrogen Energy
Nanomaterials
In this study, we examine the effect of integrating different carbon nanostructures (carbon nanot... more In this study, we examine the effect of integrating different carbon nanostructures (carbon nanotubes, CNTs, graphene nanoplatelets, GNPs) into Ni- and Ni-W-based bi-functional catalysts for hydrocracking of heptane performed at 400 °C. The effect of varying the SiO2/Al2O3 ratio of the zeolite Y support (between 5 and 30) on the heptane conversion is also studied. The results show that the activity, in terms of heptane conversion, followed the order CNT/Ni-ZY5 (92%) > GNP/Ni-ZY5 (89%) > CNT/Ni-W-ZY30 (86%) > GNP/Ni-W-ZY30 (85%) > CNT/Ni-ZY30 (84%) > GNP/Ni-ZY30 (83%). Thus, the CNT-based catalysts exhibited slightly higher heptane conversion as compared to the GNP-based ones. Furthermore, bimetallic (Ni-W) catalysts possessed higher BET surface areas (725 m2/g for CNT/Ni-W-ZY30 and 612 m2/g for CNT/Ni-ZY30) and exhibited enhanced hydrocracking activity as compared to the monometallic (Ni) catalyst with the same zeolite support and type of carbon structure. It was also...
Oxidative coupling of methane on Li/CeO2 based catalysts: Investigation of the effect of Mg- and La-doping of the CeO2 support
Molecular Catalysis, 2022
Journal of Environmental Chemical Engineering, 2022
Journal of CO2 Utilization, 2021
Applied Catalysis B: Environmental, 2021
Reaction Chemistry and Engineering, 2022
Climate change, greenhouse effect and fossil fuel extraction have gained a growing interest in re... more Climate change, greenhouse effect and fossil fuel extraction have gained a growing interest in research and industrial circles to provide alternative chemicals and fuel synthesis technologies. Carbon dioxide (CO2) hydrogenation to value-added chemicals using hydrogen (H2) from renewable power (solar, wind) offers a unique solution. From this aspect this review describes the various products, namely methane (C1), methanol, ethanol, dimethyl ether (DME) and hydrocarbons (HCs) originating via CO2 hydrogenation reaction. In addition, conventional reactor units for the CO2 hydrogenation process are explained, as well as different types of microreactors with key pathways to determine catalyst activity and selectivity of the value-added chemicals. Finally, limitations between conventional units and microreactors and future directions for CO2 hydrogenation are detailed and discussed. The benefits of such setups in providing platforms that could be utilized in the future for major scale-up and industrial operation are also emphasized.
Bimetallic Exsolved Heterostructures of Controlled Composition with Tunable Catalytic Properties
ACS Nano
Towards maximizing conversion of ethane and carbon dioxide into synthesis gas using highly stable Ni-perovskite catalysts
Journal of CO2 Utilization
Sustainability, 2022
The paper explores the potential for adaptive mitigation at the Montezuma Wildlife Refuge, Seneca... more The paper explores the potential for adaptive mitigation at the Montezuma Wildlife Refuge, Seneca Falls, NY, USA, and surrounds, focusing on landscapes along the historic Erie Canal that inadvertently lowered the water table and shrunk adjacent wetlands. Now the Erie Canal National Heritage Corridor (ECNHC), Montezuma, NY, USA, the canal, and surrounds lack a clear identity but have the potential to be repurposed as green infrastructure to support climate mitigation through the application of natural climate solutions, namely reforestation. Reforestation has been shown to produce the highest potential performance for carbon sequestration, along with a multitude of co-benefits. However, most studies assessing capacity for climate mitigation using nature-based approaches operate at a high level via remote data and do not test hypotheses at smaller scales that require groundtruthing data, parcel-by parcel approaches, and an understanding of landowner values. The initial research questi...
Ni/CNT/Zeolite-Y composite catalyst for efficient heptane hydrocracking: Steady-state and transient kinetic studies
Applied Catalysis A: General, 2022
Ir/Al2O3触媒上の亜酸化窒素低減に対するアルカリ助触媒(K)の効果
Topics in Catalysis, 2016
Journal of Environmental Chemical Engineering, 2016
The impact of H 2 as additional reducing agent on the SCR of NO with C 3 H 6 in excess oxygen, wa... more The impact of H 2 as additional reducing agent on the SCR of NO with C 3 H 6 in excess oxygen, was comparatively explored over low noble metal loading (0.5 wt%), Pt/g-Al 2 O 3 , Pd/g-Al 2 O 3 , Ir/g-Al 2 O 3 catalysts. To gain insight into the role of H 2 , the reactions NO + C 3 H 6 + O 2 (R#1), NO + C 3 H 6 + O 2 + H 2 (R#2), NO + H 2 + O 2 (R#3) were employed. In respect to propene oxidation, the Pd > Pt > Ir sequence was obtained under R#1, since they exhibit complete conversion at 220, 250, 325 C, respectively; all metals exhibit moderate deNOx performances (X NO, <40%). H 2 co-presence (R#2) promotes both the NO and C 3 H 6 conversions, which is valid in the whole temperature interval investigated (50-400 C), being more substantial for Pt/g-Al 2 O 3 and Ir/g-Al 2 O 3 , less beneficial for Pd/g-Al 2 O 3. A two-maxima feature is obtained on X NO pattern (at 100and100 and 100and230 C) of Pt and Pd during R#2. The low temperature maximum Àattributed to NO reduction by H 2-is substantially more pronounced on Pt than Pd, offering X NO 9090% and S N2 9085%; the high temperature maximum-attributed to NO reduction by C 3 H 6-is higher by $15% on both Pt and Pd, in respect to the values obtained during R#1, while S N2 remained unaffected. Different X NO pattern with one maximum is obtained over Ir, implying a synergistic interaction between H 2 and C 3 H 6. This synergy is accompanied by a substantial widening of the NO reduction window toward lower temperatures and a considerable increase on both X NO,max and S N2
Topics in Catalysis, 2016
The promoting impact of potassium (0-1 wt. % K) on nitrous oxide (N 2 O) catalytic decomposition ... more The promoting impact of potassium (0-1 wt. % K) on nitrous oxide (N 2 O) catalytic decomposition over Ir/Al 2 O 3 is investigated under both oxygen deficient and oxygen excess conditions. All samples were characterized by means of X-ray powder diffraction (XRD), temperature-programmed reduction (H 2-TPR), ammonia desorption (NH 3-TPD) and Fourier Transform Infrared Spectroscopy of pyridine adsorption (FTIR-Pyridine). The results reveal that the K-free Ir/Al 2 O 3 catalyst consists mainly of the IrO 2 phase, exhibiting also significant Lewis acidity, which is gradually eliminated by the addition of K. Catalytic performance results showed that the deN 2 O performance in the absence of O 2 in the feed mixture is negatively affected upon increasing potassium loading. However, under oxygen excess conditions, a pronounced effect of K is observed. Although the catalytic performance of the un-doped catalyst is drastically hindered by the presence of O 2 , the K-promotion notably prohibits the oxygen poisoning. The optimum deN 2 O performance is obtained with potassium loading of 0.5 wt. % K, which offers complete conversion of N 2 O at 580 ο C, instead of the corresponding 50% N 2 O conversion achieved with the unmodified sample.
Hydrogen Production via Glycerol Steam Reforming over Ni/Al2O3: Influence of Nickel Precursors
ACS Sustainable Chemistry & Engineering, 2013
Applied Catalysis B: Environmental, 2012
In this work the activity of Ni catalysts in hydrogen production by glycerol steam reforming was ... more In this work the activity of Ni catalysts in hydrogen production by glycerol steam reforming was studied. Moreover the effect of the support (TiO 2 , SBA-15 and ZrO 2) on the catalytic performance of Ni was evaluated. A strong effect of the support on the activity of the samples was detected. The Ni/TiO 2 sample showed negligible activity mainly due to the low strength of anatase to keep nickel in the reduced state. In fact, both incorporation of Ni ions into the nanoanatase lattice and oxidation of the active phase to NiO under operating conditions were observed. A deactivation process was also found with the Ni/SBA-15 sample while the best results were achieved with the Ni/ZrO 2 catalyst, showing no deactivation. After 20 hours, the glycerol conversion was 72% and the H 2 yield was 65%. The Ni/ZrO 2 sample was even more active when tested at lower temperatures, although its performance was less stable. On the basis of the experimental results, it was evidenced that the nature of the support affects above all the stability of the active phase. In particular, strong interactions between the metal active phase and the support ensures stability, activity and selectivity of the catalyst in glycerol steam reforming reactions.
Global NEST International Conference on Environmental Science & Technology
Here we report on the effect of the support and preparation method on the activity and stability ... more Here we report on the effect of the support and preparation method on the activity and stability of Ir-based catalysts under CO oxidation. Alunina-ceria-zirconia (ACZ: 60wt%Al2O3 - 40wt%CexZr1-xO2, x=0.25, 0.5, 0.75) mixed oxide supports with high oxygen storage capacity (OSC) were synthesized via two different methods, hydrothermal (ACZ-H) and co-precipitation (ACZ-P), and used as supports of Ir nanoparticles, so as, besides the Ce/Zr composition to also deal with the effect of the preparation method on catalytic performance. ACZ supports and counterpart Ir/ACZ catalysts were thoroughly characterized using various techniques, while catalytic measurements were conducted under excess O2 conditions (1.0% CO, 5.0% O2, balance He at 1 bar) in the temperature range of 100-400oC. Both pre-reduced and pre-oxidized catalysts were evaluated, while their sintering behavior after experiencing several sequential oxidative thermal aging steps was also studied. The results demonstrated superior t...
Nanomaterials
The catalytic oxidation of CO is probably the most investigated reaction in the literature, for d... more The catalytic oxidation of CO is probably the most investigated reaction in the literature, for decades, because of its extended environmental and fundamental importance. In this paper, the oxidation of CO on La1−xSrxMnO3 perovskites (LSMx), either unloaded or loaded with dispersed Ir nanoparticles (Ir/LSMx), was studied in the temperature range 100–450 °C under excess O2 conditions (1% CO + 5% O2). The perovskites, of the type La1−xSrxMnO3 (x = 0.0, 0.3, 0.5 and 0.7), were prepared by the coprecipitation method. The physicochemical and structural properties of both the LSMx and the homologous Ir/LSMx catalysts were evaluated by various techniques (XRD, N2 sorption–desorption by BET-BJH, H2-TPR and H2-Chem), in order to better understand the structure–activity–stability correlations. The effect of preoxidation/prereduction/aging of the catalysts on their activity and stability was also investigated. Results revealed that both LSMx and Ir/LSMx are effective for CO oxidation, with the...
Toward Maximizing the Selectivity of Diesel-Like Hydrocarbons from Oleic Acid Hydrodeoxygenation Using Ni/Co-Al2o3 Embedded Mesoporous Silica Nanocomposite Catalysts: An Experimental and Dft Approach
CO2 hydrogenation for the production of higher alcohols: Trends in catalyst developments, challenges and opportunities
Catalysis Today
Biogas dry reforming over Ni/LnOx-type catalysts (Ln = La, Ce, Sm or Pr)
International Journal of Hydrogen Energy
Nanomaterials
In this study, we examine the effect of integrating different carbon nanostructures (carbon nanot... more In this study, we examine the effect of integrating different carbon nanostructures (carbon nanotubes, CNTs, graphene nanoplatelets, GNPs) into Ni- and Ni-W-based bi-functional catalysts for hydrocracking of heptane performed at 400 °C. The effect of varying the SiO2/Al2O3 ratio of the zeolite Y support (between 5 and 30) on the heptane conversion is also studied. The results show that the activity, in terms of heptane conversion, followed the order CNT/Ni-ZY5 (92%) > GNP/Ni-ZY5 (89%) > CNT/Ni-W-ZY30 (86%) > GNP/Ni-W-ZY30 (85%) > CNT/Ni-ZY30 (84%) > GNP/Ni-ZY30 (83%). Thus, the CNT-based catalysts exhibited slightly higher heptane conversion as compared to the GNP-based ones. Furthermore, bimetallic (Ni-W) catalysts possessed higher BET surface areas (725 m2/g for CNT/Ni-W-ZY30 and 612 m2/g for CNT/Ni-ZY30) and exhibited enhanced hydrocracking activity as compared to the monometallic (Ni) catalyst with the same zeolite support and type of carbon structure. It was also...
Oxidative coupling of methane on Li/CeO2 based catalysts: Investigation of the effect of Mg- and La-doping of the CeO2 support
Molecular Catalysis, 2022
Journal of Environmental Chemical Engineering, 2022
Journal of CO2 Utilization, 2021
Applied Catalysis B: Environmental, 2021