TY - GEN A1 - Baena-Moreno, Francisco Manuel A1 - González-Castaño, Miriam A1 - Navarro de Miguel, Juan Carlos A1 - Miah, Kamal Uddin Mohammad A1 - Ossenbrink, Ralf A1 - Odriozola, José Antonio A1 - Arellano-García, Harvey T1 - Stepping toward Efficient Microreactors for CO2 Methanation: 3D Printed Gyroid Geometry T2 - ACS Sustainable Chemistry & Engineering N2 - This work presents a comparative study towards the development of efficient micro-reactors based on 3D-printed structures. Thus, the study evaluates the influence of the metal substrate geometry on the performance of structured catalysts for the CO2 methanation reaction. For this purpose, 0.5%Ru–15%Ni/MgAl2O4 catalyst is wash coated over two different micro-monolithic metal substrates: a conventional parallel channel honeycomb structure and a novel 3D-printed structure with a complex gyroid geometry. The effect of the metal substrate geometry is analyzed for several CO2 sources including ideal flue gas atmospheres, the presence of residual CH4 and CO in the flue gas, as well as simulated biogas sources. The advantages of the gyroid-3D complex geometries over the honeycomb structures are shown for all evaluated conditions, providing at the best-case scenario a 14% improvement of CO2 conversion. Moreover, this contribution shows that systematically tailoring geometrical features of structured catalysts becomes an effective strategy to achieve improved catalysts performances independent of the flue gas composition. By enhancing the transport processes and the gas-catalyst interactions, the employed gyroid 3D metal substrates enable boosted CO2 conversions and greater CH4 selectivity within diffusional controlled regimes. KW - CO2 methanation KW - gyroid geometry KW - CH4 selectivity KW - gyroid-3D complex Y1 - 2021 U6 - https://doi.org/10.1021/acssuschemeng.1c01980 SN - 2168-0485 VL - 9 IS - 24 SP - 8198 EP - 8206 ER - TY - GEN A1 - González-Castaño, Miriam A1 - Navarro de Miguel, Juan Carlos A1 - Pernkova, A. A1 - Centeno, Miguel Angel A1 - Odriozola, José Antonio A1 - Arellano-García, Harvey T1 - Ni/YMnO3 perovskite catalyst for CO2 methanation T2 - Applied Materials Today N2 - Ni/YMnO3 perovskite catalyst for CO2 methanation KW - Ni catalysts KW - CO2 methanation KW - YMnO3 perovskites KW - manganites Y1 - 2021 U6 - https://doi.org/10.1016/j.apmt.2021.101055 VL - 23 ER - TY - GEN A1 - Gonzalez-Castano, Miriam A1 - Navarro de Miguel, Juan Carlos A1 - Boelte, Jens-H. A1 - Centeno, Miguel Angel A1 - Klepel, Olaf A1 - Arellano-García, Harvey T1 - Assessing the impact of textural properties in Ni–Fe catalysts for CO2 methanation performance T2 - Microporous and Mesoporous Materials N2 - In heterogeneous catalysis, the benefits of employing adequate textural properties on the catalytic performances are usually stated. Nevertheless, the quantification of the extent of improvement is not an easy task since variations on the catalysts’ specific areas and pore structures might involve modifications on a number of other surface catalytic features. This study establishes the impact of the catalyst textural properties on the CO2 methanation performance by investigating bimetallic Ni–Fe catalysts supported over carbon supports with different textural properties regarding surface area and pore structure. The comparable metal loading and dispersions attained for all systems enabled establishing forthright relationships between the catalyst textural properties and CO2 methanation rate. Once the influence of the external mass diffusions on the catalysts’ performance was experimentally discarded, the estimated Thiele modulus and internal effectiveness (φ and ηEff) values showed that the catalyst performance was majorly governed by the surface reaction rate whilst the pore size affected in no significant manner within the examined range (Dpore = 10.2 to 5.8 nm). Therefore, the rapport between the catalyst performance and surface area was quantified for the CO2 methanation reaction over Ni–Fe catalysts: increasing the surface area from 572 to 802 m2/g permit obtaining ca. 10% higher CO2 conversions. KW - Ni-Fe catalysts KW - CO2 methanation KW - Surface area KW - Pore size KW - Thiele modulus Y1 - 2021 U6 - https://doi.org/10.1016/j.micromeso.2021.111405 SN - 1387-1811 VL - 327 ER - TY - GEN A1 - Mahmood, Safdar A1 - González-Castaño, Miriam A1 - Penkova, Anna A1 - Centeno, Miguel Angel A1 - Odriozola, José Antonio A1 - Arellano-García, Harvey T1 - CO2 methanation on Ni/YMn1-xAlxO3 perovskite catalysts T2 - Applied Materials Today N2 - Seeking for advanced catalytic systems for the CO2 methanation reaction, the use of Ni supported catalysts over redox materials is often proposed. Profiting the superior redox properties described for layered perovskite systems, this work has investigated a series Ni supported YMn1-xAlxO3 (x = 0, 0.2, 0.5, 0.8, 1) perovskite catalysts. The obtained results evidenced the impact of the support nature on the systems redox properties and Ni-support interactions. Within the catalysts series, the greater methanation rates displayed by Ni/YMn0.5Al0.5O3 catalyst (0.748 mmolCO2,conv.s–1 gNi –1 at 400 ◦C and 60 L/gh) were associated to the interplay between the support redox properties and superior Ni dispersion. The improved redox behavior attained through the Al-incorporation (up to x = 0.5) was associated to the layered perovskite structures which, being distorted and constituted by smaller crystal sizes, facilitated the behavior of Mn redox couples as surface species readily interconverted. Exhibiting catalytic performances comparable to precious metals based catalysts, this work proposes the Ni/YMn0.5Al0.5O3 catalyst as an effective system for the CO2 methanation reaction. KW - CO2 methanation KW - Perovskites KW - Ni catalyst KW - Manganese KW - Aluminium Y1 - 2022 U6 - https://doi.org/10.1016/j.apmt.2022.101577 SN - 2352-9407 VL - 29 SP - 1 EP - 11 ER - TY - GEN A1 - González-Castaño, Miriam A1 - Baena-Moreno, Francisco Manuel A1 - Navarro de Miguel, Juan Carlos A1 - Miah, Kamal Uddin Mohammad A1 - Arroyo-Torralvo, Fátima A1 - Ossenbrink, Ralf A1 - Odriozola, José Antonio A1 - Benzinger, Walther A1 - Hensel, Andreas A1 - Wenka, Achim A1 - Arellano-García, Harvey T1 - 3D-printed structured catalysts for CO2 methanation reaction: Advancing of gyroid-based geometries T2 - Energy Conversion and Management N2 - This work investigates the CO2 methanation rate of structured catalysts by tuning the geometry of 3D-printed metal Fluid Guiding Elements (FGEs) structures based on periodically variable pseudo-gyroid geometries. The enhanced performance showed by the structured catalytic systems is mostly associated with the capability of the FGEs substrate geometries for efficient heat usages. Thus, variations on the channels diameter resulted in ca. 25% greater CO2 conversions values at intermediate temperature ranges. The highest void fraction evidenced in the best performing catalyst (3D-1) favored the radial heat transfer and resulted in significantly enhanced catalytic activity, achieving close to equilibrium (75%) conversions at 400 ◦C and 120 mL/min. For the 3D-1 catalyst, a mathematical model based on an experimental design was developed thus enabling the estimation of its behavior as a function of temperature, spatial velocity, hydrogen to carbon dioxide (H2/CO2) ratio, and inlet CO2 concentration. Its optimal operating conditions were established under 3 different scenarios: 1) no restrictions, 2) minimum H2:CO2 ratios, and 3) minimum temperatures and H2/CO2 ratio. For instance, for the lattest scenario, the best CO2 methanation conditions require operating at 431 ◦C, 200 mL/min, H2/CO2 = 3 M ratio, and inlet CO2 concentration = 10 %. KW - 3D-printing KW - Triply periodic minimal surfaces KW - Fluid guiding elements KW - CO2 methanation KW - Structured catalysts KW - Experiment design Y1 - 2022 U6 - https://doi.org/10.1016/j.enconman.2022.115464 SN - 2590-1745 VL - 258 ER - TY - GEN A1 - Arellano-García, Harvey A1 - Safdar, Muddasar A1 - Shezad, Nasir A1 - Akhtar, Farid T1 - Development of Ni-doped A-site lanthanides-based perovskite-type oxide catalysts for CO2 methanation by auto-combustion method T2 - RSC Advances N2 - Engineering the interfacial interaction between the active metal element and support material is a promising strategy for improving the performance of catalysts toward CO2 methanation. Herein, the Ni-doped rare-earth metal-based A-site substituted perovskite-type oxide catalysts (Ni/AMnO3; A = Sm, La, Nd, Ce, Pr) were synthesized by auto-combustion method, thoroughly characterized, and evaluated for CO2 methanation reaction. The XRD analysis confirmed the perovskite structure and the formation of nano-size particles with crystallite sizes ranging from 18 to 47 nm. The Ni/CeMnO3 catalyst exhibited a higher CO2 conversion rate of 6.6 × 10−5 molCO2 gcat−1 s−1 and high selectivity towards CH4 formation due to the surface composition of the active sites and capability to activate CO2 molecules under redox property adopted associative and dissociative mechanisms. The higher activity of the catalyst could be attributed to the strong metal–support interface, available active sites, surface basicity, and higher surface area. XRD analysis of spent catalysts showed enlarged crystallite size, indicating particle aggregation during the reaction; nevertheless, the cerium-containing catalyst displayed the least increase, demonstrating resilience, structural stability, and potential for CO2 methanation reaction. KW - perovskite KW - CO2 methanation KW - lanthanide KW - auto-combustion method Y1 - 2024 UR - https://pubs.rsc.org/en/content/articlelanding/2024/ra/d4ra02106a U6 - https://doi.org/10.1039/d4ra02106a VL - 2024 IS - 14 SP - 20240 EP - 20253 ER - TY - GEN A1 - Arellano-García, Harvey A1 - Safdar, Muddasar A1 - Lewis, Allana A1 - Radacsi, Norbert A1 - Fan, Xianfeng A1 - Huang, Yi T1 - Superhydrophobic ZIF-67 with exceptional hydrostability T2 - Materials Today Advances N2 - In this work, cosolvent-stabilized superhydrophobic, highly hydrostable ZIF-67 was synthesized at room temperature using a facile, one-pot hydrothermal synthesis route, and the effect of cosolvent concentration on ZIF-67 crystal structure properties and hydrostability was studied systematically. The underlying mechanism for the cosolvent-supported hydrostability improvement was also proposed. Furthermore, the influence of hydrotreatment on the resultant ZIF-67s' catalytic performance was studied in the ‘Sabatier reaction’ for CO2 to synthetic natural gas (CH4) conversion. KW - ZIF-67 KW - Superhydrophobicity KW - Hydrostability KW - Cosolvent-stabilization KW - CO2 methanation Y1 - 2023 U6 - https://doi.org/10.1016/j.mtadv.2023.100448 SN - 2590-0498 VL - Vol. 20 ER - TY - GEN A1 - Gonzalez-Castãno, Miriam A1 - Morales, Carlos A1 - Navarro de Miguel, Juan Carlos A1 - Boelte, Jens-H. A1 - Klepel, Olaf A1 - Flege, Jan Ingo A1 - Arellano-García, Harvey T1 - Are Ni/ and Ni5Fe1/biochar catalysts suitable for synthetic natural gas production? A comparison with γ-Al2O3 supported catalysts T2 - Green Energy & Environment N2 - Among challenges implicit in the transition to the post–fossil fuel energetic model, the finite amount of resources available for the technological implementation of CO2 revalorizing processes arises as a central issue. The development of fully renewable catalytic systems with easier metal recovery strategies would promote the viability and sustainability of synthetic natural gas production circular routes. Taking Ni and NiFe catalysts supported over γ-Al2O3 oxide as reference materials, this work evaluates the potentiality of Ni and NiFe supported biochar catalysts for CO2 methanation. The development of competitive biochar catalysts was found dependent on the creation of basic sites on the catalyst surface. Displaying lower Turn Over Frequencies than Ni/Al catalyst, the absence of basic sites achieved over Ni/C catalyst was related to the depleted catalyst performances. For NiFe catalysts, analogous Ni5Fe1 alloys were constituted over both alumina and biochar supports. The highest specific activity of the catalyst series, exhibited by the NiFe/C catalyst, was related to the development of surface basic sites along with weaker NiFe–C interactions, which resulted in increased Ni0:NiO surface populations under reaction conditions. In summary, the present work establishes biochar supports as a competitive material to consider within the future low-carbon energetic panorama. KW - Biochar catalysts KW - Carbon catalysts KW - Ni catalysts KW - NiFe alloy KW - Bimetallic catalysts KW - Synthetic natural gas KW - CO2 methanation Y1 - 2023 U6 - https://doi.org/10.1016/j.gee.2021.05.007 SN - 2468-0257 VL - 8 IS - 3 SP - 744 EP - 756 ER - TY - GEN A1 - Shezad, Nasir A1 - Safdar, Muddasar A1 - Arellano-Garcia, Harvey A1 - Tai, Cheuk-Wai A1 - Chen, Shaojiang A1 - Seo, Dong-Kyun A1 - You, Shujie A1 - Vomiero, Alberto A1 - Akhtar, Farid T1 - Deciphering the role of APTES in tuning the metal support interaction of NiO nanolayers over hierarchical zeolite 13X for CO2 methanation T2 - Carbon Capture Science & Technology N2 - The development of robust nickel catalysts on porous substrates offers great potential for converting carbon dioxide (CO2) into methane, thereby helping to address the global warming and sustainability challenges. This study investigates the dispersion and stability of Ni nanolayers by grafting bifunctional groups over the hierarchical zeolite 13X (h13X) support using (3-aminopropyl)triethoxysilane (APTES). The Ni nanolayers, with a thickness of 1.5-7 nm, were deposited around the edges of h13X and analyzed using STEM imaging. A clear shift in the binding energies was observed by XPS analysis, substantiating the enhanced metalsupport interaction (MSI) between NiO and h13X. The influence of reaction temperature on APTES incorporation into h13X was revealed by H2-TPR and CO2-TPD, with notable variations in the reducibility and surface basicity profiles of the catalysts. The optimized catalyst exhibited CO2 conversion of 61% with CH4 selectivity of 97% under GHSV of 60,000 mlgCat-1h-1 at 400 oC and 1 bar and demonstrated robust stability over a period of 150 h without discernible degradation. The enhanced performance could be attributed to the strengthened MSI and reduced size of Ni nanolayers over h13X. These findings highlight the development of robust heterogeneous catalysts by changing the surface chemistry of support material for various catalytic applications. KW - CO2 methanation KW - Catalyst stability KW - Metal-support interaction KW - APTES functionalization KW - Nickel nanolayers KW - Hierarchical zeolite Y1 - 2025 UR - https://www.sciencedirect.com/science/article/pii/S2772656825000636 U6 - https://doi.org/10.1016/j.ccst.2025.100424 VL - 15 SP - 1 EP - 11 PB - Elsevier CY - Amsterdam ER -