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Research on nickel-based catalysts for carbon dioxide methanation combined with literature measurement. J CO2 UTIL 2022. [DOI: 10.1016/j.jcou.2022.102117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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2
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On the Optimization of Ni/A and Ni/X Synthesis Procedure toward Active and Selective Catalysts for the Production of CH4 from CO2. Catalysts 2022. [DOI: 10.3390/catal12080823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Herein, optimization of zeolite NaA/NaX synthesis conditions in order to obtain the final product with high surface area and pore volume was investigated. An optimal synthesis condition was 5 days aging time and crystallization time of 9 h with the co-addition of cetyltrimethylammonium bromide (CTAB) and heptane. All those optimal synthesis conditions provided mixed phase between zeolite NaA and NaX, and addition of those organic phases improved the surface area and pore volume of the final synthesized zeolite. The role of CTAB and heptane on increasing the surface area of zeolite was studied by in situ small-angle X-ray scattering (SAXS). The SAXS results evidenced that small nucleation precursor was formed upon the addition of organic phase, and this nucleation precursor can provide zeolite with high-characteristic XRD signals of mixed phase of zeolite A and X after the crystallization process. The synthesized zeolite obtained from optimal synthesis condition with high surface area was further used as a catalyst support by impregnating with 5, 10, 15, and 20wt%Ni for catalyzing CO2 methanation reaction. The results found that 15wt%Ni/zeolite expressed the highest catalytic activity with high CH4 selectivity and stability. This was due to high dispersion of Ni species on catalyst surface and high metal-support interaction between Ni and zeolite. These results indicated that the mixed phase zeolite support can be a potential catalyst support for this reaction.
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Mao GC, Kan XT, Xiao MX, Liu WL, Dong BX, Teng YL. Alkaline Earth Metal-Induced Hydrogenation of the CaO-Captured CO 2 to Methane at Room Temperature. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c01479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Guo-Cui Mao
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China
| | - Xiao-Tian Kan
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China
| | - Ming-Xiu Xiao
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China
| | - Wen-Long Liu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China
| | - Bao-Xia Dong
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China
| | - Yun-Lei Teng
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China
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Jiang F, Jiang F, Wang S, Xu Y, Liu B, Liu X. Catalytic Activity for CO2 Hydrogenation is Linearly Dependent on Generated Oxygen Vacancies over CeO2‐Supported Pd Catalysts. ChemCatChem 2022. [DOI: 10.1002/cctc.202200422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Feng Jiang
- Jiangnan University Department of Chemical Engineering No. 1800 Lihu Avenue 214122 Wuxi CHINA
| | - Feng Jiang
- Jiangnan University Department of Chemical Engineering CHINA
| | - Shanshan Wang
- Jiangnan University Department of Chemical Engineering CHINA
| | - Yuebing Xu
- Jiangnan University Department of Chemical Engineering CHINA
| | - Bing Liu
- Jiangnan University Department of Chemical Engineering CHINA
| | - Xiaohao Liu
- Jiangnan University School of Chemical and Material Engineering No. 1800 Lihu Avenue 214122 Wuxi CHINA
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Abstract
High-efficiency utilization of CO2 facilitates the reduction of CO2 concentration in the global atmosphere and hence the alleviation of the greenhouse effect. The catalytic hydrogenation of CO2 to produce value-added chemicals exhibits attractive prospects by potentially building energy recycling loops. Particularly, methanol is one of the practically important objective products, and the catalytic hydrogenation of CO2 to synthesize methanol has been extensively studied. In this review, we focus on some basic concepts on CO2 activation, the recent research advances in the catalytic hydrogenation of CO2 to methanol, the development of high-performance catalysts, and microscopic insight into the reaction mechanisms. Finally, some thinking on the present research and possible future trend is presented.
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6
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Research Progress and Reaction Mechanism of CO2 Methanation over Ni-Based Catalysts at Low Temperature: A Review. Catalysts 2022. [DOI: 10.3390/catal12020244] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The combustion of fossil fuels has led to a large amount of carbon dioxide emissions and increased greenhouse effect. Methanation of carbon dioxide can not only mitigate the greenhouse effect, but also utilize the hydrogen generated by renewable electricity such as wind, solar, tidal energy, and others, which could ameliorate the energy crisis to some extent. Highly efficient catalysts and processes are important to make CO2 methanation practical. Although noble metal catalysts exhibit higher catalytic activity and CH4 selectivity at low temperature, their large-scale industrial applications are limited by the high costs. Ni-based catalysts have attracted extensive attention due to their high activity, low cost, and abundance. At the same time, it is of great importance to study the mechanism of CO2 methanation on Ni-based catalysts in designing high-activity and stability catalysts. Herein, the present review focused on the recent progress of CO2 methanation and the key parameters of catalysts including the essential nature of nickel active sites, supports, promoters, and preparation methods, and elucidated the reaction mechanism on Ni-based catalysts. The design and preparation of catalysts with high activity and stability at low temperature as well as the investigation of the reaction mechanism are important areas that deserve further study.
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7
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Evaluation of novel ZnO–Ag cathode for CO2 electroreduction in solid oxide electrolyser. J Solid State Electrochem 2022. [DOI: 10.1007/s10008-021-05103-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
AbstractCO2 and steam/CO2 electroreduction to CO and methane in solid oxide electrolytic cells (SOEC) has gained major attention in the past few years. This work evaluates, for the very first time, the performance of two different ZnO–Ag cathodes: one where ZnO nanopowder was mixed with Ag powder for preparing the cathode ink (ZnOmix–Ag cathode) and the other one where Ag cathode was infiltrated with a zinc nitrate solution (ZnOinf –Ag cathode). ZnOmix–Ag cathode had a better distribution of ZnO particles throughout the cathode, resulting in almost double CO generation while electrolysing both dry CO2 and H2/CO2 (4:1 v/v). A maximum overall CO2 conversion of 48% (in H2/CO2) at 1.7 V and 700 °C clearly indicated that as low as 5 wt% zinc loading is capable of CO2 electroreduction. It was further revealed that for ZnOinf –Ag cathode, most of CO generation took place through RWGS reaction, but for ZnOmix–Ag cathode, it was the synergistic effect of both RWGS reaction and CO2 electrolysis. Although ZnOinf –Ag cathode produced trace amount of methane at higher voltages, with ZnOmix–Ag cathode, there was absolutely no methane. This seems to be due to strong electronic interaction between Zn and Ag that might have suppressed the catalytic activity of the cathode towards methanation.
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9
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Summa P, Świrk K, Wierzbicki D, Motak M, Alxneit I, Rønning M, Da Costa P. Co-Precipitated Ni-Mg-Al Hydrotalcite-Derived Catalyst Promoted with Vanadium for CO 2 Methanation. Molecules 2021; 26:molecules26216506. [PMID: 34770915 PMCID: PMC8588090 DOI: 10.3390/molecules26216506] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/21/2021] [Accepted: 10/25/2021] [Indexed: 11/16/2022] Open
Abstract
Co-precipitated Ni-Mg-Al hydrotalcite-derived catalyst promoted with vanadium were synthesized with different V loadings (0–4 wt%) and studied in CO2 methanation. The promotion with V significantly changes textural properties (specific surface area and mesoporosity) and improves the dispersion of nickel. Moreover, the vanadium promotion strongly influences the surface basicity by increasing the total number of basic sites. An optimal loading of 2 wt% leads to the highest activity in CO2 methanation, which is directly correlated with specific surface area, as well as the basic properties of the studied catalysts.
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Affiliation(s)
- Paulina Summa
- Institut Jean Le Rond d’Alembert, Sorbonne Université, CNRS UMR 7190, 78210 Saint-Cyr-L’Ecole, France
- Faculty of Energy and Fuels, AGH University of Science and Technology, 30-059 Kraków, Poland; (D.W.); (M.M.)
- Correspondence: (P.S.); (P.D.C.)
| | - Katarzyna Świrk
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (K.Ś.); (M.R.)
| | - Dominik Wierzbicki
- Faculty of Energy and Fuels, AGH University of Science and Technology, 30-059 Kraków, Poland; (D.W.); (M.M.)
- Paul Scherrer Institut (PSI), 5232 Villigen, Switzerland;
| | - Monika Motak
- Faculty of Energy and Fuels, AGH University of Science and Technology, 30-059 Kraków, Poland; (D.W.); (M.M.)
| | - Ivo Alxneit
- Paul Scherrer Institut (PSI), 5232 Villigen, Switzerland;
| | - Magnus Rønning
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (K.Ś.); (M.R.)
| | - Patrick Da Costa
- Institut Jean Le Rond d’Alembert, Sorbonne Université, CNRS UMR 7190, 78210 Saint-Cyr-L’Ecole, France
- Correspondence: (P.S.); (P.D.C.)
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Alam MI, Cheula R, Moroni G, Nardi L, Maestri M. Mechanistic and multiscale aspects of thermo-catalytic CO 2 conversion to C 1 products. Catal Sci Technol 2021; 11:6601-6629. [PMID: 34745556 PMCID: PMC8521205 DOI: 10.1039/d1cy00922b] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 08/26/2021] [Indexed: 12/04/2022]
Abstract
The increasing environmental concerns due to anthropogenic CO2 emissions have called for an alternate sustainable source to fulfill rising chemical and energy demands and reduce environmental problems. The thermo-catalytic activation and conversion of abundantly available CO2, a thermodynamically stable and kinetically inert molecule, can significantly pave the way to sustainably produce chemicals and fuels and mitigate the additional CO2 load. This can be done through comprehensive knowledge and understanding of catalyst behavior, reaction kinetics, and reactor design. This review aims to catalog and summarize the advances in the experimental and theoretical approaches for CO2 activation and conversion to C1 products via heterogeneous catalytic routes. To this aim, we analyze the current literature works describing experimental analyses (e.g., catalyst characterization and kinetics measurement) as well as computational studies (e.g., microkinetic modeling and first-principles calculations). The catalytic reactions of CO2 activation and conversion reviewed in detail are: (i) reverse water-gas shift (RWGS), (ii) CO2 methanation, (iii) CO2 hydrogenation to methanol, and (iv) dry reforming of methane (DRM). This review is divided into six sections. The first section provides an overview of the energy and environmental problems of our society, in which promising strategies and possible pathways to utilize anthropogenic CO2 are highlighted. In the second section, the discussion follows with the description of materials and mechanisms of the available thermo-catalytic processes for CO2 utilization. In the third section, the process of catalyst deactivation by coking is presented, and possible solutions to the problem are recommended based on experimental and theoretical literature works. In the fourth section, kinetic models are reviewed. In the fifth section, reaction technologies associated with the conversion of CO2 are described, and, finally, in the sixth section, concluding remarks and future directions are provided.
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Affiliation(s)
- Md Imteyaz Alam
- Laboratory of Catalysis and Catalytic Processes, Dipartimento di Energia, Politecnico di Milano Via La Masa 34 20156 Milano Italy
| | - Raffaele Cheula
- Laboratory of Catalysis and Catalytic Processes, Dipartimento di Energia, Politecnico di Milano Via La Masa 34 20156 Milano Italy
| | - Gianluca Moroni
- Laboratory of Catalysis and Catalytic Processes, Dipartimento di Energia, Politecnico di Milano Via La Masa 34 20156 Milano Italy
| | - Luca Nardi
- Laboratory of Catalysis and Catalytic Processes, Dipartimento di Energia, Politecnico di Milano Via La Masa 34 20156 Milano Italy
| | - Matteo Maestri
- Laboratory of Catalysis and Catalytic Processes, Dipartimento di Energia, Politecnico di Milano Via La Masa 34 20156 Milano Italy
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11
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Biswas S, Kundu C, Kulkarni AP, Kattel S, Giddey S, Bhattacharya S. A Study on CO 2 Hydrogenation Using a Ceria–Zirconia Mixed Oxide (Ce xZr 1–xO 2)-Supported Fe Catalyst. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c03044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Saheli Biswas
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - Chandan Kundu
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - Aniruddha P. Kulkarni
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - Shyam Kattel
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, United States
| | - Sarbjit Giddey
- CSIRO Energy, Private Bag 10, Clayton South, Melbourne, Victoria 3169, Australia
| | - Sankar Bhattacharya
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
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12
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Chu M, Liu Y, Gong J, Zhang C, Wang X, Zhong Q, Wu L, Xu Y. Suppressing Dehydroisomerization Boosts n-Butane Dehydrogenation with High Butadiene Selectivity. Chemistry 2021; 27:11643-11648. [PMID: 34089282 DOI: 10.1002/chem.202101087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Indexed: 11/12/2022]
Abstract
Butadiene (BD) is a critical raw material in chemical industry, which is conventionally produced from naphtha cracking. The fast-growing demand of BD and the limited oil reserve motivate chemists to develop alternative methods for BD production. Shale gas, which mainly consists of light alkanes, has been considered as cheap raw materials to replace oil for BD production via n-butane direct dehydrogenation (n-BDH). However, the quest for highly-efficient catalysts for n-BDH is driven by the current drawback of low BD selectivity. Here, we demonstrate a strategy for boosting the selectivity of BD by suppressing dehydroisomerization, an inevitable step in the conventional n-BDH process which largely reduces the selectivity of BD. Detailed investigations show that the addition of alkali-earth metals (e. g., Mg and Ca) into Pt-Ga2 O3 /S10 catalysts increases Pt dispersity, suppresses coke deposition and dehydroisomerization, and thus leads to the significant increase of BD selectivity. The optimized catalyst displays an initial BD selectivity of 34.7 % at a n-butane conversion of 82.1 % at 625 °C, which outperforms the reported catalysts in literatures. This work not only provides efficient catalysts for BD production via n-BDH, but also promotes the researches on catalyst design in heterogeneous catalysis.
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Affiliation(s)
- Mingyu Chu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Yu Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Jin Gong
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Congyang Zhang
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario, N6 A 5B7, Canada
| | - Xuchun Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Qixuan Zhong
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Linzhong Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Yong Xu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, No. 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China.,Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage Devices, Collaborative Innovation Center of Advanced Energy Materials, School of Materials and Energy, Guangdong University of Technology, Guangzhou, 510006, Guangdong, P. R. China
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Sholeha NA, Mohamad S, Bahruji H, Prasetyoko D, Widiastuti N, Abdul Fatah NA, Jalil AA, Taufiq-Yap YH. Enhanced CO 2 methanation at mild temperature on Ni/zeolite from kaolin: effect of metal-support interface. RSC Adv 2021; 11:16376-16387. [PMID: 35479131 PMCID: PMC9031409 DOI: 10.1039/d1ra01014j] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 04/26/2021] [Indexed: 11/25/2022] Open
Abstract
Catalytic CO2 hydrogenation to CH4 offers a viable route for CO2 conversion into carbon feedstock. The research aimed to enhance CO2 conversion at low temperature and to increase the stability of Ni catalysts using zeolite as a support. NaZSM-5 (MFI), NaA (LTA), NaY (FAU), and NaBEA (BEA) synthesized from kaolin were impregnated with 15% Ni nanoparticles in order to elucidate the effect of surface area, porosity and basicity of the zeolite in increasing Ni activity at mild temperature of ∼200 °C. A highly dispersed Ni catalyst was produced on high surface area NaY meanwhile the mesoporosity of ZSM-5 has no significant effect in improving Ni dispersion. However, the important role of zeolite mesoporosity was observed on the stability of the catalyst. Premature deactivation of Ni/NaA within 10 h was due to the relatively small micropore size that restricted the CO2 diffusion, meanwhile Ni/NaZSM-5 with a large mesopore size exhibited catalytic stability for 40 h of reaction. Zeolite NaY enhanced Ni activity at 200 °C to give 21% conversion with 100% CH4 selectivity. In situ FTIR analysis showed the formation of hydrogen carbonate species and formate intermediates at low temperatures on Ni/NaY, which implied the efficiency of electron transfer from the basic sites of NaY during CO2 reduction. The combination of Ni/NaY interfacial interaction and NaY surface basicity promoted CO2 methanation reaction at low temperature. Different Na-zeolites as supports of Ni metal were successfully synthesized from kaolin-based material. Combination of interfacial interaction Ni-support and surface basicity promoted CO2 methanation reaction at a low temperature of ∼200 °C.![]()
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Affiliation(s)
- Novia Amalia Sholeha
- Department of Chemistry, Faculty of Science and Data Analytics, Institut Teknologi Sepuluh Nopember ITS, Keputih, Sukolilo Surabaya 60111 Indonesia
| | - Surahim Mohamad
- Departement of Chemistry, Faculty of Science, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
| | - Hasliza Bahruji
- Centre of Advanced Material and Energy Science, Universiti Brunei Darussalam Jalan Tungku Link BE 1410 Brunei Darussalam
| | - Didik Prasetyoko
- Department of Chemistry, Faculty of Science and Data Analytics, Institut Teknologi Sepuluh Nopember ITS, Keputih, Sukolilo Surabaya 60111 Indonesia
| | - Nurul Widiastuti
- Department of Chemistry, Faculty of Science and Data Analytics, Institut Teknologi Sepuluh Nopember ITS, Keputih, Sukolilo Surabaya 60111 Indonesia
| | - Nor Aiza Abdul Fatah
- Department of Chemical Engineering, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia 81310 UTM, Skudai Johor Bahru Malaysia
| | - Aishah Abdul Jalil
- Department of Chemical Engineering, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia 81310 UTM, Skudai Johor Bahru Malaysia.,Centre of Hydrogen Energy, Institute of Future Energy, Universiti Teknologi Malaysia 81310 UTM, Skudai Johor Bahru Malaysia
| | - Yun Hin Taufiq-Yap
- Departement of Chemistry, Faculty of Science, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
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CO2 Methanation of Biogas over 20 wt% Ni-Mg-Al Catalyst: on the Effect of N2, CH4, and O2 on CO2 Conversion Rate. Catalysts 2020. [DOI: 10.3390/catal10101201] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Biogas contains more than 40% CO2 that can be removed to produce high quality CH4. Recently, CH4 production from CO2 methanation has been reported in several studies. In this study, CO2 methanation of biogas was performed over a 20 wt% Ni-Mg-Al catalyst, and the effects of CO2 conversion rate and CH4 selectivity were investigated as a function of CH4, O2, H2O, and N2 compositions of the biogas. At a gas hourly space velocity (GHSV) of 30,000 h−1, the CO2 conversion rate was ~79.3% with a CH4 selectivity of 95%. In addition, the effects of the reaction temperature (200–450 °C), GHSV (21,000–50,000 h−1), and H2/CO2 molar ratio (3–5) on the CO2 conversion rate and CH4 selectivity over the 20 wt% Ni-Mg-Al catalyst were evaluated. The characteristics of the catalyst were analyzed using Brunauer–Emmett–Teller surface area analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The catalyst was stable for approximately 200 h at a GHSV of 30,000 h−1 and a reaction temperature of 350 °C. CO2 conversion and CH4 selectivity were maintained at 75% and 93%, respectively, and the catalyst was therefore concluded to exhibit stable activity.
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