Effect of Ni/Co Ratio on Bimetallic Oxide Supported Silica Catalyst in CO2 Methanation

2015 ◽  
Vol 802 ◽  
pp. 431-436
Author(s):  
Siti Aminah Md Ali ◽  
Ku Halim Ku Hamid ◽  
Kamariah Noor Ismail

Five series of silica supported bimetallic oxide (NiCo/SiO2) catalysts have been synthesized through successive reverse co-precipitation and wet impregnation methods at different metal loadings (i.e. 80Ni20Co/SiO2,, 60Ni40Co/SiO2,50Ni50Co/SiO2,40Ni60Co/SiO2,20Ni80Co/SiO2). The catalytic performance of these catalysts were tested for the CO2methanation catalysis using microactivity fixed bed reactor. Nickel rich catalyst (80Ni20Co/SiO2) exhibited the highest catalytic activity in the CO2methanation with 47.1% of CO2conversion. Meanwhile, the CH4selectivity and yield was found to be at 99.9% and 27%, respectively.

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.


2013 ◽  
Vol 690-693 ◽  
pp. 1529-1534
Author(s):  
Wen Gui Gao ◽  
Hua Wang ◽  
Wen Yan Liu ◽  
Feng Jie Zhang

A series of CuO-ZnO-Al2O3catalysts modified by different promoter were prepared by co-precipitation or incipient wet impregnation and characterized by X-ray diffraction (XRD), N2physisorption, hydrogen temperature-programmed reduction (H2-TPR) and carbon dioxide temperature-programmed desorption (CO2-TPD). The modified catalysts were tested for methanol synthesis from CO/CO2co-hydrogenation in a fixed bed reactor with feed containing CO, CO2and H2(CO:CO2:H2=1.0:1.08:6.24, volume radio). It is revealed that the catalysts modified by Zr, Mg, Ca has higher activity of methanol synthesis by CO and CO2co-hydrogenation. Especially, the addition of Zr enhances the conversion of total carbon and the selectivity of methanol, which is due to the improved surface area, much more active sites, and the synergistically interaction between CuO and ZnO caused by the addition of Zr promoter.


2009 ◽  
Vol 16 (03) ◽  
pp. 343-349 ◽  
Author(s):  
YUZHOU YING ◽  
KANKA FENG ◽  
ZHIGUO LV ◽  
ZHENMEI GUO ◽  
JINSHENG GAO

Nano copper-based catalysts were prepared by co-precipitation method and the performance of catalytic hydrogenation for methyl 3-hydroxypropionate (MHP) to 1, 3-propanediol (1, 3-PDO) on the nano catalysts were studied under a high-pressure microcontinuum fixed-bed reactor. The effects of structure, texture, and composition of the catalysts on the catalytic performance were investigated by characterizing the catalysts with XRD, TG–DTG, SEM, and N 2 adsorption/desorption analysis technique. The results showed that addition of promoters enhanced the activity and selectivity of copper-based catalysts, which promoted the dispersion of the active components effectively and stabilized the active center of the catalysts. Especially, the copper-based catalyst of loaded P could restrain side-reaction effectively and improve selectivity obviously, the conversion of MHP and the selectivity of 1, 3-PDO could be 91.30% and reach 90.15%, respectively.


Catalysts ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 752 ◽  
Author(s):  
Yingquan Wu ◽  
Li Tan ◽  
Tao Zhang ◽  
Hongjuan Xie ◽  
Guohui Yang ◽  
...  

Two types of amorphous ZrO2 (am-ZrO2) catalysts were prepared by different co-precipitation/reflux digestion methods (with ethylenediamine and ammonia as the precipitant respectively). Then, copper and potassium were introduced for modifying ZrO2 via an impregnation method to enhance the catalytic performance. The obtained catalysts were further characterized by means of Brunauer-Emmett-Teller surface areas (BET), X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR), and In situ diffuse reflectance infrared spectroscopy (in situ DRIFTS). CO hydrogenation experiments were performed in a fixed-bed reactor for isobutanol synthesis. Great differences were observed on the distribution of alcohols over the two types of ZrO2 catalysts, which were promoted with the same content of Cu and K. The selectivity of isobutanol on K-CuZrO2 (ammonia as precipitant, A-KCZ) was three times higher than that on K-CuZrO2 (ethylenediamine as precipitant, E-KCZ). The characterization results indicated that the A-KCZ catalyst supplied more active hydroxyls (isolated hydroxyls) for anchoring and dispersing Cu. More importantly, it was found that bicarbonate species were formed, which were ascribed as important C1 species for isobutanol formation on the A-KCZ catalyst surface. These C1 intermediates had relatively stronger adsorption strength than those adsorbed on the E-KCZ catalyst, indicating that the bicarbonate species on the A-KCZ catalyst had a longer residence time for further carbon chain growth. Therefore, the selectivity of isobutanol was greatly enhanced. These findings would extend the horizontal of direct alcohols synthesis from syngas.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2017
Author(s):  
Yuliya Gulyaeva ◽  
Maria Alekseeva (Bykova) ◽  
Olga Bulavchenko ◽  
Anna Kremneva ◽  
Andrey Saraev ◽  
...  

The heightened interest in liquid organic hydrogen carriers encourages the development of catalysts suitable for multicycle use. To ensure high catalytic activity and selectivity, the structure–reactivity relationship must be extensively investigated. In this study, high-loaded Ni–Cu catalysts were considered for the dehydrogenation of methylcyclohexane. The highest conversion of 85% and toluene selectivity of 70% were achieved at 325 °C in a fixed-bed reactor using a catalyst with a Cu/Ni atomic ratio of 0.23. To shed light on the relationship between the structural features and catalytic performance, the catalysts were thoroughly studied using a wide range of advanced physicochemical tools. The activity and selectivity of the proposed catalysts are related to the uniformity of Cu distribution and its interaction with Ni via the formation of metallic solid solutions. The method of introduction of copper in the catalyst plays a crucial role in the effectiveness of the interaction between the two metals.


2019 ◽  
Vol 15 (1) ◽  
pp. 112-118
Author(s):  
Nastaran Parsafard ◽  
Mohammad Hasan Peyrovi ◽  
Zahra Mohammadian ◽  
Niloofar Atashi

CoMo-supported mesoporous catalysts were synthesized by 50 wt% of HZSM-5 and 50 wt% of FSM-16, KIT-6, and MCM-48. These catalysts were prepared by the wet-impregnation method and pre-sulfided with CS2. The catalytic performance was evaluated for HDS reaction of dibenzothiophene over a temperature range of 250-400 °C in a micro fixed-bed reactor under atmospheric pressure. The supported CoMo bimetallic catalysts were characterized by XRD, XRF, FT-IR, N2 adsorption-desorption, and SEM. The CoMo/KIT-6/HZSM-5 indicate higher activity than other catalysts at 400 °C for dibenzothiophene hydrodesulphurization. Also, the best selectivity to cyclohexylbenzene (CHB) is related to CoMo/FSM-16/HZSM-5. The activation energy was also calculated for all prepared catalysts for the conversions of less than 10%; according to which, the activation energy for CoMo/KIT-6/HZSM-5 is less than other catalysts (~21 kJ/mol) which can be related to the appropriate pore size and high surface area of the support. Copyright © 2020 BCREC Group. All rights reserved 


2010 ◽  
Vol 132 ◽  
pp. 228-235 ◽  
Author(s):  
Xu Li ◽  
Guan Zhong Lu ◽  
Yang Long Guo ◽  
Yun Guo ◽  
Yan Qin Wang

A novel solid superbase catalyst of La2O3-ZnO/ZrO2 was prepared, and its H– value (Hammett function) of surface basic strength reaches 26.5. The catalytic activity of La2O3-ZnO/ZrO2 was evaluated for the transesterification of soybean oil (SBO) with methanol to biodiesel in a fixed bed reactor under atmospheric pressure. The results show that the chemical composition of the La2O3-ZnO/ZrO2 catalyst influences both its H– value and catalytic performance, the appropriate content of ZrO2 is 60 wt.% and the La2O3/ZnO molar ratio is 4~5/1. La2O3-ZnO/ZrO2 is an effective catalyst for the transesterification of SBO, and the SBO conversion reaches 71.3% at 70°C for 12h.


2007 ◽  
Vol 119 ◽  
pp. 251-254 ◽  
Author(s):  
Ji Chul Jung ◽  
Hee Soo Kim ◽  
Ahn Seop Choi ◽  
Young Min Chung ◽  
Tae Jin Kim ◽  
...  

α-Bi2Mo3O12 and γ-Bi2MoO6 catalysts were prepared by co-precipitation method, and they were applied to the oxidative dehydrogenation of n-butene into 1,3-butadiene in a continuous flow fixed-bed reactor. Formation of α-Bi2Mo3O12 and γ-Bi2MoO6 catalysts was well confirmed by XRD, Raman spectroscopy, and ICP-AES analyses. The γ-Bi2MoO6 catalyst exhibited a better catalytic performance than the α-Bi2Mo3O12 catalyst. Catalytic performance of γ-Bi2MoO6 strongly depended on the pH value used in the co-precipitation step. It was also revealed that a mixed catalyst comprising γ-Bi2MoO6 (90 wt%) and small amount of α-Bi2Mo3O12 (10 wt%) showed the best catalytic performance due to the synergy effect of two components. It is believed that the high catalytic performance of the mixed catalyst resulted from high diffusion coefficient of lattice oxygen in the γ-Bi2MoO6 and from abundant chemisorption sites for n-butene in the α-Bi2Mo3O12.


Author(s):  
Radwa A. El-Salamony ◽  
Sara A. El-Sharaky ◽  
Seham A. Al-Temtamy ◽  
Ahmed M. Al-Sabagh ◽  
Hamada M. Killa

Abstract Recently, because of the increasing demand for natural gas and the reduction of greenhouse gases, interests have focused on producing synthetic natural gas (SNG), which is suggested as an important future energy carrier. Hydrogenation of CO2, the so-called methanation reaction, is a suitable technique for the fixation of CO2. Nickel supported on yttrium oxide and promoted with cobalt were prepared by the wet-impregnation method respectively and characterized using SBET, XRD, FTIR, XPS, TPR, and HRTEM/EDX. CO2 hydrogenation over the Ni/Y2O3 catalyst was examined and compared with Co–Ni/Y2O3 catalysts, Co% = 10 and 15 wt/wt. The catalytic test was conducted with the use of a fixed-bed reactor under atmospheric pressure. The catalytic performance temperature was 350 °C with a supply of H2:CO2 molar ratio of 4 and a total flow rate of 200 mL/min. The CH4 yield was reached 67%, and CO2 conversion extended 48.5% with CO traces over 10Co–Ni/Y2O3 catalyst. This encourages the direct methanation reaction mechanism. However, the reaction mechanism over Ni/Y2O3 catalyst shows different behaviors rather than that over bi-metal catalysts, whereas the steam reforming of methane reaction was arisen associated with methane consumption besides increase in H2 and CO formation; at the same temperature reaction.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ahmad Asghari ◽  
Mohammadreza Khanmohammadi Khorrami ◽  
Sayed Habib Kazemi

AbstractThe present work introduces a good prospect for the development of hierarchical catalysts with excellent catalytic performance in the methanol to aromatic hydrocarbons conversion (MTA) process. Hierarchical H-ZSM5 zeolites, with a tailored pore size and different Si/Al ratios, were synthesized directly using natural kaolin clay as a low-cost silica and aluminium resource. Further explored for the direct synthesis of hierarchical HZSM-5 structures was the steam assisted conversion (SAC) with a cost-effective and green affordable saccharide source of high fructose corn syrup (HFCS), as a secondary mesopore agent. The fabricated zeolites exhibiting good crystallinity, 2D and 3D nanostructures, high specific surface area, tailored pore size, and tunable acidity. Finally, the catalyst performance in the conversion of methanol to aromatic hydrocarbons was tested in a fixed bed reactor. The synthesized H-ZSM5 catalysts exhibited superior methanol conversion (over 100 h up to 90%) and selectivity (over 85%) in the methanol conversion to aromatic hydrocarbon products.


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