The Effect of CeO2 and Fe2O3 Dopants on Ni/ Alumina Based Catalyst for Dry Reforming of Methane to Hydrogen

2011 ◽  
Vol 364 ◽  
pp. 519-523 ◽  
Author(s):  
S. Sivasangar ◽  
Yun Hin Taufiq-Yap

Methane reforming is the most feasible techniques to produce hydrogen for commercial usage. Hence, dry reforming is the environment friendly method that uses green house gases such as CO2and methane to produce fuel gas. Catalysts play a vital role in methane conversion by enhancing the reforming process. In this study Ni/γ-Al2O3was selected as based catalyst and CeO2and Fe2O3dopants were added to investigate their effect on catalytic activity in dry reforming. The catalysts synthesized through wet impregnation method and characterized by using XRD, TEM and SEM-EDX. The catalytic tests were carried out using temperature programmed reaction (TPRn) and the products were detected by using an online mass spectrometer. The results revealed that these dopants significantly affect the catalytic activity and selectivity of the catalyst during reaction. Hence, Fe2O3doped catalyst shows higher hydrogen production with stable catalytic activity.

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3347
Author(s):  
Arslan Mazhar ◽  
Asif Hussain Khoja ◽  
Abul Kalam Azad ◽  
Faisal Mushtaq ◽  
Salman Raza Naqvi ◽  
...  

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process.


Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 242
Author(s):  
Ahmed A. Ibrahim ◽  
Ahmed S. Al-Fatesh ◽  
Nadavala Siva Kumar ◽  
Ahmed E. Abasaeed ◽  
Samsudeen O. Kasim ◽  
...  

Dry reforming of methane (DRM) was studied in the light of Ni supported on 8%PO4 + ZrO2 catalysts. Cerium was used to modify the Ni active metal. Different percentage loadings of Ce (1%, 1.5%, 2%, 2.5%, 3%, and 5%) were tested. The wet incipient impregnation method was used for the preparation of all catalysts. The catalysts were activated at 700 °C for ½ h. The reactions were performed at 800 °C using a gas hourly space velocity of 28,000 mL (h·gcat)−1. X-ray diffraction (XRD), N2 physisorption, hydrogen temperature programmed reduction (H2-TPR), temperature programmed oxidation (TPO), temperature programmed desorption (TPD), and thermogravimetric analysis (TGA) were used for characterizing the catalysts. The TGA analysis depicted minor amounts of carbon deposition. The CO2-TPD results showed that Ce enhanced the basicity of the catalysts. The 3% Ce loading possessed the highest surface area, the largest pore volume, and the greatest pore diameter. All the promoted catalysts enhanced the conversions of CH4 and CO2. Among the promoted catalysts tested, the 10Ni + 3%Ce/8%PO4 + ZrO2 catalyst system operated at 1 bar and at 800 °C gave the highest conversions of CH4 (95%) and CO2 (96%). The stability profile of Cerium-modified catalysts (10%Ni/8%PO4 + ZrO2) depicted steady CH4 and CO2 conversions during the 7.5 h time on stream.


Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1335
Author(s):  
Seol A Shin ◽  
Ali Alizadeh Eslami ◽  
Young Su Noh ◽  
Hyun-tae Song ◽  
Hyun Dong Kim ◽  
...  

Recently, the dry reforming of methane (DRM) has received much attention as a conversion technology of greenhouse gases. Ni-based catalysts supported on ternary metal oxide composite (ZrTiAlOx) were prepared to improve the coke resistance properties in the DRM (CH4:CO2 = 1) at low temperature. The ZrTiAlOx supports with different ratios of Zr/Ti were prepared through the modified Pechini sol-gel method, and then the Ni was impregnated on the synthesized support via the incipient wetness impregnation method. Considering the Zr/Ti ratios, different catalytic activity and durability in the DRM were identified. The Ni/ZrTiAlOx catalyst with Zr/Ti of 2 exhibited enhanced coke inhibition property compared to the others at low temperature DRM for 50 h. The catalysts with a high Zr/Ti ratio under the same condition were rapidly deactivated, while the catalyst with a low Zr/Ti ratio showed deficient activity. It was found from temperature-programmed surface reactions (TPSR) and DRIFTS (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) analysis that the addition of Ti has led in to higher catalytic stability at Zr/Ti = 2, which could be as a result of oxygen vacancies generated by the ternary metal oxides. Ni/ZrTiAlOx catalyst with ratio of Zr/Ti = 2 showed high stability and good catalytic activity towards DRM for the production of syngas.


2013 ◽  
Vol 634-638 ◽  
pp. 563-566
Author(s):  
Fu Chen Ding ◽  
Cui Tao Ren ◽  
Bin Li ◽  
Hong Wang ◽  
Cui Qing Li

The LaBO3/HZSM-5 samples were prepared by the impregnation method. The structure of catalysts was examined by XRD. The catalytic activity for the combustion of soot particulate was evaluated by a technique of the temperature-programmed reaction. In the LaBO3/HZSM-5 catalyst, the Mn as B-site ion, the catalyst was the good candidate catalyst for the soot catalytic combustion. In the LaMnO3/HZSM-5 catalyst, the catalytic activity was tunable by changing the metal components of the perovskite-type oxide at B-site, the Fe partial substitution for Mn of LaMnO3/HZSM-5 enhanced the catalytic activity, and the combustion temperature of soot particle was lower than LaMnO3/HZSM-5 sample without substitution, corresponding Tm of 401oC and the selectivity of CO2 77.0%.


Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1777 ◽  
Author(s):  
Anis Hamza Fakeeha ◽  
Samsudeen Olajide Kasim ◽  
Ahmed Aidid Ibrahim ◽  
Ahmed Elhag Abasaeed ◽  
Ahmed Sadeq Al-Fatesh

A promising method to reduce global warming has been methane reforming with CO2, as it combines two greenhouse gases to obtain useful products. In this study, Ni-supported catalysts were synthesized using the wet impregnation method to obtain 5%Ni/Al2O3(SA-5239), 5%Ni/Al2O3(SA-6175), 5%Ni/SiO2, 5%Ni/MCM41, and 5%Ni/SBA15. The catalysts were tested in dry reforming of methane at 700 °C, 1 atm, and a space velocity of 39,000 mL/gcat h, to study the interaction of Ni with the supports, and evaluation was based on CH4 and CO2 conversions. 5%Ni/Al2O3(SA-6175) and 5%Ni/SiO2 gave the highest conversion of CH4 (78 and 75%, respectively) and CO2 (84 and 82%, respectively). The catalysts were characterized by some techniques. Ni phases were identified by X-ray diffraction patterns. Brunauer–Emmett–Teller analysis showed different surface areas of the catalysts with the least being 4 m2/g and the highest 668 m2/g belonging to 5%Ni/Al2O3(SA-5239) and 5%Ni/SBA15, respectively. The reduction profiles revealed weak NiO-supports interaction for 5%Ni/Al2O3(SA-5239), 5%Ni/MCM41, and 5%Ni/SBA15; while strong interaction was observed in 5%Ni/Al2O3(SA-6175) and 5%Ni/SiO2. The 5%Ni/Al2O3(SA-6175) and 5%Ni/SiO2 were close with respect to performance; however, the former had a higher amount of carbon deposit, which is mostly graphitic, according to the conducted thermal analysis. Carbon deposits on 5%Ni/SiO2 were mainly atomic in nature.


Catalysts ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1174
Author(s):  
Magdalena Mosinska ◽  
Waldemar Maniukiewicz ◽  
Malgorzata I. Szynkowska-Jozwik ◽  
Pawel Mierczynski

The oxy-steam reforming of liquefied natural gas reaction (OSR-LNG) is promising process for syngas generation. In this paper, the catalytic properties of NiO/La2O3 systems prepared by wet impregnation and co-precipitation methods were extensively investigated in OSR-LNG reaction. The physicochemical properties of the studied catalytic materials were determined using various techniques including Temperature programmed reduction (TPR-H2), Temperature programmed desorption (TPD-NH3), Brunauer, Emmett and Teller (BET), X-ray diffraction (XRD) and Scanning electron microscopy (SEM) with an energy dispersive X-Ray spectrometer (EDS). Reactivity measurements performed in the OSR-LNG process showed that the catalyst preparation method and the calcination temperature significantly affected the activity of NiO/La2O3 catalysts in the OSR-LNG reaction. The catalytic activity tests showed that NiO/La2O3 system prepared by a wet impregnation method and calcined at 700 °C showed the total conversion of the LNG component at 900 °C and the highest H2 yield at 700 and 900 °C. The phase composition studies confirmed the formation of the LaNiO3 structure in the case of the NiO/La2O3 catalyst prepared by wet impregnation, calcined at the temperature of 700 °C. Catalytic activity measurements showed that the reactivity of the catalysts was related to their phase composition and acidity. SEM images of spent catalysts showed that the smallest amount of carbon deposit was detected on the surface of the most active systems.


Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1220
Author(s):  
Linghui Lyu ◽  
Yunxing Han ◽  
Qingxiang Ma ◽  
Shengene Makpal ◽  
Jian Sun ◽  
...  

Dry reforming of methane (DRM) can effectively convert two greenhouse gases into high-valued chemicals, in which the syngas produced by the reaction can be directly used as raw gases for Fischer–Tropsch synthesis and methanol synthesis. Ni-based catalysts for the DRM reaction with comparable initial activity to noble metals are the focus of most researchers, but their poor carbon deposition resistance easily causes their low stability. More importantly, the nickel loading will affect the catalytic activity and carbon deposition resistance of the catalyst. Herein, a series of Ni/Al2O3 catalysts with bimodal pores was prepared and characterized by X-ray diffraction (XRD), N2 physical adsorption–desorption, H2-temperature programmed reduction (H2-TPR), temperature programmed hydrogenation (TPH), Raman, and thermogravimetric analysis (TG). The results show that the interesting bimodal structure catalysts could provide a high surface area and contribute to the mass transfer. Besides, the catalytic performance of the DRM reaction is sensitive to nickel loadings. In this study, the Ni/Al2O3 catalyst with nickel loadings of 6% and 8% exhibited excellent catalytic activity and carbon deposition resistance. These findings will provide a new strategy to design a highly efficient and stable heterogeneous catalyst for industry.


2020 ◽  
Vol 72 (4) ◽  
pp. 99-109
Author(s):  
Xiaofeng Zhu ◽  
Teng Zhao ◽  
Yufan Huang ◽  
Zijun Wang

Layered porous SiO2 (V-SiO2) was designed and prepared from vermiculite by expansion-acidification method, and then used as a catalyst support to prepare Ni/V-SiO2 for dry reforming of methane. It is well known that sintering and carbon deposition of metal particles are two main problems in deactivation of nickel-based catalysts for methane dry reforming. It is reported that strong metal support interaction is a possible solution. Here, a Ni/V-SiO2-H catalyst derived from Ni-phyllosilicate was developed, and compared with the catalyst Ni/V-SiO2-IM by impregnation method. The results showed that the Ni/V-SiO2-H catalyst had high catalytic activity and stability, and the CH4 conversion reached 71.7% at 700 �C. The reason is that on the one hand, the active metal particles in the catalyst are small (8.3 nm) and relatively evenly dispersed; on the other hand, the catalyst has strong metal support interaction, which improves the anti sintering ability of the catalyst and affects the catalytic activity. It is considered that V-SiO2 as a catalyst support for the preparation of Ni-phyllosilicate may have wide application.


2011 ◽  
Vol 8 (s1) ◽  
pp. S349-S357 ◽  
Author(s):  
Mingxin Guo ◽  
Rongshu Zhu ◽  
Minhua Dong ◽  
Feng Ouyang

The behaviour of a series of Ir-based catalysts supported on SiO2, ZSM-5 and γ-Al2O3 with various Ir loadings prepared by impregnation method was conducted by temperature programmed reaction (TPR) technique. The result implies that NO is oxidized to NO2while simultaneously being reduced to N2or N2O in the NO reactions over iridium catalysts. The surface active phase over iridium catalysts that promote the NO reactions is IrO2. The catalytic activity increases with the increase of the Ir loading and support materials have a little effect on the catalytic activity. When the loading is less than 0.1%, the catalytic activity was found to be dependent on the nature of support materials and in order: Ir/ZSM-5>Ir/γ-Al2O3>Ir/SiO2. When the loading is higher than 0.1%, the catalytic activity for NO oxidation is in order: Ir/ZSM-5>Ir/SiO2>Ir/γ -Al2O3, which is correlated with Ir dispersion on the surface of support materials and the catalytic activity for NO reduction is in sequence: Ir/γ -Al2O3>Ir/SiO2>Ir/ZSM-5, which is attributed to the adsorbed-dissociation of NO2. Compared to Pt/γ-Al2O3, Ir/γ-Al2O3catalyst is more benefit for the NO reduction.


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