04777ntm a2200361 i 4500 0 0 lcc 0 1 REF 10000 10000 REF 2022-01-25 0 FTKKP .M89 2021 r Thesis T000001757 2022-05-18 00:00:00 1 2022-01-25 THESIS 0 0 lcc 0 1 REF 10000 10000 REF 2022-03-29 0 CD13046 T000001758 2023-01-30 00:00:00 1 2022-03-29 THESIS 96575 96581 MY-KuUP 20251125110003.0 t||||fr|||| 000 0 220329s2021 my a|||frm||| 000 0 eng d THE0009188(Local) hardback UMP eng UMP rda FTKKP .M89 2021 r Thesis Mohamad Muzakkir Tajuddin, author. Synthesis and characterization of nickel based catalyst modified with lanthanum oxide supported on silica for methane cracking / Mohamad Muzakkir Tajuddin Kuantan, Pahang : UMP, 2021 © 2021 xii, 82 pages : illustrations (some color) ; 30 cm. + 1 CD-ROM text rdacontent text rdacontent unmediated rdamedia computer rdamedia volume rdacarrier computer disc rdacarrier text file PDF rda Faculty of Chemical and Process Engineering Technology Thesis (Master of Science) -- Universiti Malaysia Pahang – 2021 Includes bibliographical references Methane cracking is an environmental friendly process to convert the main greenhouse gas; methane into hydrogen and carbon. However, catalysts prepared through the conventional methods such as impregnation and co-precipitation suffer low metal dispersion and poor control surface composition. In this work, glycine nitrate process (GNP) and in situ glycine nitrate process (in situ GNP) have been employed for preparation of Ni-La and Ni-La/SiO2 catalysts, respectively. The main aim of this work is to produce catalyst with high Ni dispersion which is ~40% thus an excellent catalytic activity in methane cracking which is ~10% hydrogen yield. In this study, Ni-La catalysts were initially synthesized using GNP at different calcination temperatures (600, 700, 800 °C) and glycine-nitrate ratios (G/N ratio= 0.5, 1.0, 1.5). The glycine-nitrate solution was heated to yield a gel-like liquid. The gel was further heated until it was self-ignited and produced an ash powder. Later, in the presence of SiO2 support, Ni-La/SiO2 catalysts were prepared via in situ GNP at different La loadings (0, 5, 20 wt%), catalyst-to-support ratios (1:2, 1:5, 1:8) and SiO2 particle sizes using SiO2(A),74 μm and SiO2(B),44 μm. The catalytic performance of Ni-La/SiO2 catalyst was investigated under methane cracking at 500 °C for 5 hrs. The catalyst was also tested for reaction gas concentration (CH4:N2 =1:2,1:4). The characterizations of Ni-La and Ni-La/SiO2 catalysts were conducted using X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM) for crystallite phase and morphology investigation. In the early study, the optimal calcination temperature and G/N ratio for Ni-La catalyst were found to be at 800 °C and 1.0, respectively. Later, during the Ni-La/SiO2 catalytic activity in methane cracking, it was observed that the presence of 5% La in the catalyst has increased the catalytic stability in hydrogen yield for 300 minutes. Meanwhile, although catalyst-to-support ratio has shown no obvious effect towards methane conversion, the catalyst-to-support ratio of 1:5 has been selected as the optimum ratio based on hydrogen yield stability. The performance of Ni-La/SiO2 catalyst of a smaller support size (44 μm), Ni-La/SiO2(B) was compared to Ni-La/SiO2(A) with a larger support size (74 μm). Ni-La/SiO2(B) is expected to have higher support surface area and this has led to high Ni dispersion as calculated which is 54.6%. Thus, a stable CH4 conversion and better H2 yield were achieved which were ~40% and ~10% using NiLa/SiO2(B) catalyst. Finally, catalyst performance with low methane concentration (CH4:N2 = 1:4) was better which is ~10% hydrogen yield compared to one with high concentration of methane ((CH4:N2 = 1:2) which is ~2%. At high methane concentration, rapid carbon accumulation is expected thus caused lower availability of active sites for further reaction. As a conclusion, the utilization of in situ GNP and the investigation of various parameters in this study has offered the synthesis of Ni-La/SiO2 catalyst with high Ni dispersion. Better Ni dispersion with 40.7% improvement has successfully resulted in a better catalyst activity and stability in methane cracking for hydrogen production. Faculty of Chemical and Process Engineering Technology Dissertations Universities and colleges Dissertations Theses lcc THESIS