Thunyathon KludpantanapanPaveenuch NantapongRaminda RattanaamonkulchaiAtthapon SrifaWanida Koo-AmornpattanaWeerawut ChaiwatChularat SakdaronnarongTawatchai CharinpanitkulSuttichai AssabumrungratSuwimol WongsakulphasatchMasao SudohRyo WatanabeChoji FukuharaSakhon RatchahatShizuoka UniversityKing Mongkut's University of Technology North BangkokChulalongkorn UniversityMahidol UniversityAmano Institute of Technology2022-08-042022-08-042021-11-08International Journal of Hydrogen Energy. Vol.46, No.77 (2021), 38175-38190036031992-s2.0-85116017216https://repository.li.mahidol.ac.th/handle/123456789/76891In this study, hydrogen and carbon nanotubes (CNTs) are simultaneously produced via a synergistic combined process of CO2 methanation (METH) and chemical vapor deposition (CVD) processes using biogas as a feedstock. METH process could upgrade CO2 containing biogas into CH4-rich gas which then decomposed into H2 and forming CNTs over CoMo/MgO catalyst by CVD process. The effects of Ce addition to CoMo/MgO were investigated. Comprehensive characterization confirms that all as-synthesized samples composed of well-aligned multi-walled carbon nanotubes (MWCNTs) with a narrow size distribution. The Ce addition improved CoMo dispersion on MgO, resulting in smaller and uniform CNTs. The small addition of Ce into CoMo/MgO catalyst could enhance the production CNTs yield. The higher Ce addition would, however, result in the CNTs yield decreased, attributed to a high basicity of CeO2 surface and a large coverage of CeO2 on the catalyst surface. The IG/ID increased with increased Ce addition, while the surface area monotonically decreased, attributed to a decrease in defects of nanotubes. In addition, this wisely combined process could result in a remarkable 100%CO2 elimination, while high CH4 conversion of 90% was obtained. The H2 production yield could gain more than 30 vol% with respect to H2 in the feed stream. The H2 yield and purity in the effluent gas stream were approximately 90%.Mahidol UniversityEnergyPhysics and AstronomyArticleSCOPUS10.1016/j.ijhydene.2021.09.068