Effects of preparation method and Sm2O3 promoter on CO methanation by a mesoporous NiO–Sm2O3/Al2O3 catalyst

2018 ◽  
Vol 42 (15) ◽  
pp. 13096-13106 ◽  
Author(s):  
Qing Liu ◽  
Hongyuan Yang ◽  
Hao Dong ◽  
Wei Zhang ◽  
Bing Bian ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Preparation Method ◽  
High Catalytic Activity ◽  
Co Methanation ◽  
Methanation Reaction ◽  
Ordered Mesoporous ◽  
Al2o3 Catalyst

Well-dispersed Ni and Sm2O3 nanoparticles embedded in an ordered mesoporous Al2O3 material simultaneously exhibit high catalytic activity and stability for the CO methanation reaction.

Active phase of highly active Co3O4 catalyst for synthetic natural gas production

RSC Advances ◽  
2014 ◽  
Vol 4 (100) ◽  
pp. 57185-57191 ◽  
Author(s):  
Baowei Wang ◽  
Sihan Liu ◽  
Zongyuan Hu ◽  
Zhenhua Li ◽  
Xinbin Ma
Keyword(s):  
Catalytic Activity ◽  
Low Temperature ◽  
Natural Gas ◽  
Active Phase ◽  
Gas Production ◽  
High Catalytic Activity ◽  
Co Methanation ◽  
Synthetic Natural Gas ◽  
Highly Active ◽  
Catalytic Stability

Co3O4 nanoparticles showed high catalytic activity for low temperature CO methanation. CoO is the active phase of the catalyst. Pre-reduction treatment can improve catalytic stability.

Comparison of the effects of the catalyst preparation method and CeO2 morphology on the catalytic activity of Pt/CeO2 catalysts for the water-gas shift reaction

2020 ◽  
Vol 10 (18) ◽  
pp. 6299-6308 ◽  
Author(s):  
Yeol-Lim Lee ◽  
Anush Mnoyan ◽  
Hyun-Suk Na ◽  
Seon-Yong Ahn ◽  
Kyoung-Jin Kim ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Oxygen Vacancies ◽  
Preparation Method ◽  
Catalyst Preparation ◽  
Water Gas Shift ◽  
High Catalytic Activity ◽  
Water Gas Shift Reaction ◽  
Key Factors ◽  
Shift Reaction ◽  
Water Gas

The key factors (Pt0 dispersion & oxygen vacancies) should maintain high values to attain high catalytic activity and they are directly affected by the morphology and the preparation method of the catalyst.

High Catalytic Activity of Pt/Al2O3 Catalyst in CO Oxidation at Room Temperature—A New Insight into Strong Metal–Support Interactions

Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1475
Author(s):  
Ireneusz Kocemba ◽  
Izabela Śmiechowicz ◽  
Marcin Jędrzejczyk ◽  
Jacek Rogowski ◽  
Jacek Michał Rynkowski
Keyword(s):  
Catalytic Activity ◽  
Co Oxidation ◽  
Room Temperature ◽  
Oxygen Adsorption ◽  
High Catalytic Activity ◽  
Adsorption Sites ◽  
Co Oxidation Reaction ◽  
Metal Support ◽  
Metal Support Interactions ◽  
Al2o3 Catalyst

The concept of very strong metal–support interactions (VSMSI) was defined in regard to the interactions that influence the catalytic properties of catalysts due to the creation of a new phase as a result of a solid-state chemical reaction between the metal and support. In this context, the high catalytic activity of the 1%Pt/Al2O3 catalyst in the CO oxidation reaction at room temperature was explained. The catalyst samples were reduced at different temperatures ranging from 500 °C to 800 °C and characterized using TPR, O2/H2 titration, CO chemisorption, TPD-CO, FTIR-CO, XRD, and TOF-SIMS methods. Based on the obtained results, it was claimed that with very high temperature reduction (800 °C), nonstoichiometric platinum species [Pt(Cl)Ox] strongly anchored to Al2O3 surface are formed. These species act as the oxygen adsorption sites.

Catalytic activity and mechanism of ordered mesoporous iron oxides on hydrogen peroxide for degradation of norfloxacin in water at neutral pH

2017 ◽  
Vol 14 (6) ◽  
pp. 361 ◽  
Author(s):  
Zhen Yuan ◽  
Minghao Sui ◽  
Jianrui Yang ◽  
Pan Li ◽  
Zhiran Liu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
High Specific Surface Area ◽  
High Catalytic Activity ◽  
Water And Wastewater Treatment ◽  
H2o2 Decomposition ◽  
Neutral Ph ◽  
Treatment Techniques ◽  
Ordered Mesoporous ◽  
H2o2 Oxidation ◽  
Decomposition Of H2o2

Environmental contextNorfloxacin is widely used as a human and veterinary medicine for its broad-spectrum antibacterial activity. It is chemically stable, rendering it difficult to remove from water using the traditional water and wastewater treatment techniques. We investigate the use of iron oxide catalysts for the degradation of norfloxacin in water prior to its release into the environment. AbstractThe catalytic activity of ordered mesoporous Fe2O3 (om-Fe2O3) on H2O2 oxidation of norfloxacin (NOR) under neutral pH conditions in water was investigated. Using non-ordered-mesoporous Fe2O3 as a reference (nom-Fe2O3), om-Fe2O3 with high specific surface area of 176.4m2g−1 and a uniform pore structure exhibited high catalytic activity in the decomposition of H2O2 as well as the degradation of NOR at neutral pH. Compared with nom-Fe2O3, om-Fe2O3 promoted the decomposition of H2O2 differently. The adsorption capacity of om-Fe2O3 for NOR was much higher than that of nom-Fe2O3. The adsorption efficiency of NOR on om-Fe2O3 accounted for 60.2–64.9% of the degradation efficiency in om-Fe2O3/H2O2. tert-Butanol (TBA), which is resistant to adsorption by om-Fe2O3, had no effect on the degradation of NOR by om-Fe2O3/H2O2. However, the presence of tromethamine (TMA), which was favourable to adsorption by om-Fe2O3, inhibited the degradation of NOR significantly. Based on the different effects of TBA and TMA on the degradation of NOR, it is proposed that the catalytic degradation of NOR may occur on the surface of om-Fe2O3. Hydroxyl radicals (·OH) generated may be bound on the surface of om-Fe2O3 without diffusing into aqueous solution. It is proposed that the adsorption of target organic pollutants must be considered when assessing the suitability of the om-Fe2O3/H2O2 process. The mechanism of om-Fe2O3 in promoting H2O2 decomposition into OH was also investigated.

Surface Functionalization of Ordered Mesoporous Hollow Carbon Spheres with Ru Organometallic Compounds as Supports of Low-Pt Content Nanocatalysts for Alkaline Hydrogen and Oxygen Evolution Reactions

MRS Advances ◽  
2020 ◽  
Vol 5 (57-58) ◽  
pp. 2973-2989
Author(s):  
J.C. Martínez-Loyola ◽  
I.L. Alonso-Lemus ◽  
M.E. Sánchez-Castro ◽  
B. Escobar-Morales ◽  
J.R. Torres-Lubián ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
High Performance ◽  
Pt Nanoparticles ◽  
Organometallic Compounds ◽  
High Catalytic Activity ◽  
Carbon Spheres ◽  
Ordered Mesoporous ◽  
Electrochemical Water Splitting ◽  
Hollow Carbon ◽  
Hollow Carbon Spheres

AbstractHerein, we report a methodology that leads to the formation of Ru metallic sites, followed by the development and anchorage of Pt-Ru alloyed nanoparticles on the surface of Ordered Mesoporous Hollow Carbon Spheres (OMHCS). Along with the Ru sites, it is demonstrated that the functionalization promotes the formation of functional groups on the surface of the OMHCS. In a first stage, OMHCS are functionalized with the [(η6-C6H5OCH2CH2OH)RuCl2]2 (Ru-dim) and [(η6-C6H4CH(CH3)2CH3)RuCl2]2 (Ru-cym) organometallic compounds. Afterwards, Pt nanoparticles are dispersed by the microwave-assisted polyol method over the functionalized supports obtaining the low-metal content 5 wt. % Pt/OMHCSRu-dim and Pt/OMHCSRu-cym nanocatalysts. The degree of Ru alloyed is found to be around 35%. The low-Pt content Pt/OMHCSRu-cym and Pt/OMHCSRu-dim exhibit a higher catalytic activity for the Oxygen (OER) and the Hydrogen (HER) Evolution Reactions than the Pt/C benchmark and the Pt/OMHCS nanocatalysts. The overpotential for the OER at 10 mA cm-2 (ηOER) is 300 mV and 210 mV smaller at Pt/OMHCSRu-cym and Pt/OMHCSRu-dim compared to Pt/C, respectively. The corresponding values of the HER at -10 mA cm-2 (ηHER) are 14 and 18 mV smaller, respectively. The high catalytic activity of Pt/OMHCSRu-cym and Pt/OMHCSRu-dim has been attributed in part to the presence of Ru0 and RuO2 species from organometallic functionalization, and the modification of the d-valence band of Pt. Their high performance for the OER and the HER opens new lines of research for the design of nanocatalysts for alkaline electrochemical water splitting.

The Relation between Catalytic Activity of CO Oxidation and Support Structure in Oxidation Catalysts using Gold Nanoparticles

2005 ◽  
Vol 900 ◽  
Author(s):  
Shiho Nagano ◽  
Koji Tajiri ◽  
Yutaka Tai
Keyword(s):  
Gold Nanoparticles ◽  
Catalytic Activity ◽  
Co Oxidation ◽  
Preparation Method ◽  
Surface Condition ◽  
Silica Aerogels ◽  
High Catalytic Activity ◽  
Support Materials ◽  
Co Oxidation Reaction ◽  
The Difference

ABSTRACTThiol-passivated gold nanoparticles were adsorbed on several kinds of support materials such as titania-coated silica aerogels and xerogels etc., and then the thiol was removed by heat treatment. The catalytic activity of the prepared composites for CO oxidation reaction was measured, and the effects of the support on the catalytic activity were investigated. Density of the supports, namely, whether aerogel supports or xerogel ones, hardly affected the catalytic activity. It was found that the catalysts having high catalytic activity could be obtained by this preparation method, even using the xerogels as the support. Calcination of the supports before adsorption of the gold nanoparticles affected the activity. The difference of the catalytic activity was observed between the composites with same gold nanoparticle size, so it was considered that the surface condition of the support materials affects the state of gold nanoparticles in composite.

Highly stable Ni/SiC catalyst modified by Al2O3 for CO methanation reaction

RSC Advances ◽  
2016 ◽  
Vol 6 (12) ◽  
pp. 9631-9639 ◽  
Author(s):  
Guojing Jin ◽  
Fangna Gu ◽  
Qing Liu ◽  
Xiaoyan Wang ◽  
Lihua Jia ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Heat Conductivity ◽  
Co Methanation ◽  
Methanation Reaction ◽  
Good Catalytic Activity

Ni/Al2O3–SiC exhibits good catalytic activity and stability due to excellent heat conductivity of SiC and enhanced interactions between Ni and support by alumina modification, thus inhibiting the migration of Ni particles.

scholarly journals Ni-Mo Sulfide Semiconductor Catalyst with High Catalytic Activity for One-Step Conversion of CO2 and H2S to Syngas in Non-Thermal Plasma

Catalysts ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 525 ◽  
Author(s):  
Xiaozhan Liu ◽  
Lu Zhao ◽  
Ying Li ◽  
Kegong Fang ◽  
Minghong Wu
Keyword(s):  
Catalytic Activity ◽  
Thermal Plasma ◽  
Economic Benefits ◽  
High Catalytic Activity ◽  
Ambient Conditions ◽  
Syngas Production ◽  
One Step ◽  
Non Thermal Plasma ◽  
Al2o3 Catalyst ◽  
Mo Sulfide

Carbon dioxide (CO2) and hydrogen sulfide (H2S) ordinarily coexist in many industries, being considered as harmful waste gases. Simultaneously converting CO2 and H2S into syngas (a mixture of CO and H2) will be a promising economic strategy for enhancing their recycling value. Herein, a novel one-step conversion of CO2 and H2S to syngas induced by non-thermal plasma with the aid of Ni-Mo sulfide/Al2O3 catalyst under ambient conditions was designed. The as-synthesized catalysts were characterized by using XRD, nitrogen sorption, UV-vis, TEM, SEM, ICP, and XPS techniques. Ni-Mo sulfide/Al2O3 catalysts with various Ni/Mo molar ratios possessed significantly improved catalytic performances, compared to the single-component catalysts. Based on the modifications of the physical and chemical properties of the Ni-Mo sulfide/Al2O3 catalysts, the variations in catalytic activity are carefully discussed. In particular, among all the catalysts, the 5Ni-3Mo/Al2O3 catalyst exhibited the best catalytic behavior with high CO2 and H2S conversion at reasonably low-energy input in non-thermal plasma. This method provides an alternative route for syngas production with added environmental and economic benefits.

Highly Ordered Mesoporous WO3 with Excellent Catalytic Performance and Reusability for Deep Oxidative Desulfurization

NANO ◽  
2015 ◽  
Vol 10 (05) ◽  
pp. 1550075 ◽  
Author(s):  
Zhenghua Li ◽  
Heon Jong Jeong ◽  
Kumarsrinivasan Sivaranjani ◽  
Byung Jin Song ◽  
Su Bin Park ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Oxidative Desulfurization ◽  
High Catalytic Activity ◽  
Ordered Mesoporous ◽  
Model Oil ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Highly ordered mesoporous tungsten trioxide ( WO 3) with high surface area (75 m2/g) and well-defined mesopores were successfully prepared through a hard templating method using a mesoporous silica KIT-6 as a template and ( NH 4)6 H 2 W 12 O 40 ⋅ x H 2 O as a tungsten precursor. Oxidative desulfurization of a model oil with H 2 O 2 as the oxidant was carried out at 50°C under atmospheric pressure in order to analyze the catalytic activity. The desulfurization reactions were optimized by various kinds of reaction parameters such as H 2 O 2/ S molar ratio, reaction temperatures and series of sulfur-containing compounds [dibenzothiophene (DBT), benzothiophene (BT) and 4,6-dimethyl dibenzothiophene (4,6-DMBT)]. Excellent catalytic activity for the removal of the sulfur-containing compounds from the model oil was observed with mesoporous WO 3 catalyst, where the activity was maintained during 5 recycle tests without any regeneration process. The high catalytic activity and durability is mainly attributed to well-defined mesopores and high surface area of mesoporous WO 3 catalyst.

Sign in / Sign up

Export Citation Format

Share Document