Rationally designing mixed Cu–(μ-O)–M (M = Cu, Ag, Zn, Au) centers over zeolite materials with high catalytic activity towards methane activation

2018 ◽  
Vol 20 (41) ◽  
pp. 26522-26531 ◽  
Author(s):  
Guiru Wang ◽  
Ling Huang ◽  
Wei Chen ◽  
Jian Zhou ◽  
Anmin Zheng
Keyword(s):  
Catalytic Activity ◽  
Direct Conversion ◽  
Methane Activation ◽  
High Catalytic Activity ◽  
Conversion Of Methane ◽  
First Time ◽  
Periodic Dft

The direct conversion of methane to methanol on [Cu(μ-O)M]2+ (M = Cu, Ag, Zn, Au) bimetal centers in ZSM-5 zeolite is investigated using periodic DFT for the first time.

Catalytic activity of palladium-doped silver dilute nanoalloys for formate oxidation from a theoretical perspective

2019 ◽  
Vol 21 (40) ◽  
pp. 22598-22610 ◽  
Author(s):  
Nan Zhang ◽  
Fuyi Chen ◽  
Longfei Guo
Keyword(s):  
Catalytic Activity ◽  
Oxidation Reaction ◽  
Theoretical Perspective ◽  
Single Atom ◽  
High Catalytic Activity ◽  
Formate Oxidation ◽  
First Time ◽  
Single Atom Alloys

We demonstrate for the first time that the Pd1Ag single-atom alloys exhibit a high catalytic activity for formate oxidation reaction.

Direct Synthesis and Catalytic Reactivity of Highly Ordered Large-Pore Methylaminopropyl-Functionalized SBA-15 Materials

2005 ◽  
Vol 58 (7) ◽  
pp. 507 ◽  
Author(s):  
Xueguang Wang ◽  
Soofin Cheng
Keyword(s):  
Catalytic Activity ◽  
Inorganic Salt ◽  
Direct Synthesis ◽  
Initial Mixture ◽  
Tetraethyl Orthosilicate ◽  
High Catalytic Activity ◽  
Amino Groups ◽  
Large Pore ◽  
Catalytic Reactivity ◽  
First Time

Highly ordered large-pore SBA-15 materials functionalized with a high loading of amino groups were synthesized for the first time by co-condensation of tetraethyl orthosilicate (TEOS) and [3-(methylamino)propyl]trimethoxysilane (MAPTMS) using an amphiphilic block copolymer. Addition of inorganic salt to the initial mixture greatly enhanced the mesostructure ordering and stability of the mesoporous materials. The materials thus obtained showed high catalytic activity and selectivity for the synthesis of flavanones by means of the Claisen–Schmidt condensation in the absence of solvent.

Characterization of Modified HZSM–5 with Gallium and its Reactivity in Direct Conversion of Methane to Liquid Hydrocarbons

2012 ◽  
Author(s):  
Nor Aishah Saidina Amin ◽  
Asmadi Ali
Keyword(s):  
Catalytic Activity ◽  
Ion Exchange ◽  
Zeolite Catalyst ◽  
Nitrogen Adsorption ◽  
Direct Conversion ◽  
Liquid Hydrocarbons ◽  
Exchange Method ◽  
Conversion Of Methane ◽  
Ion Exchange Method

Mangkin zeolit HZSM–5 diubahsuai secara kaedah pertukaran ion berasid bagi menghasilkan mangkin zeolit Ga–HZSM–5. Aktiviti bermangkin bagi HZSM–5 dan Ga–HZSM–5 dikaji pada suhu tindak balas 800°C dan halaju ruang jaman masa (GHSV) 7500 jam–1. Mangkin HZSM–5 dan Ga–HZSM–5 dicirikan secara XRD, NMR, Penjerapan Nitrogen dan TPD. Hasil pencirian menunjukkan aluminium keluar dari kerangka asal. HZSM–5 yang mengandungi galium adalah mangkin yang lebih baik daripada mangkin zeolit HZSM–5 bagi menghasilkan cecair hidrokarbon. Kata kunci: Ga-HZSM-5; metana; pertukaran ion berasid; cecair hidrokarbon The HZSM–5 zeolite catalyst was modified by an acidic ion exchange method to produce the Ga–HZSM–5 zeolite catalyst. The catalytic activity of HZSM–5 and Ga–HZSM–5 were studied at reaction temperature of 800°C and gas hourly space velocities (GHSV) of 7500 hr–1. HZSM–5 and Ga–HZSM–5 catalysts were characterized by XRD, NMR, Nitrogen Adsorption and TPD. The characterization results revealed that aluminium was removed from the parent framework. Gallium loaded HZSM–5 is a better catalyst than HZSM–5 zeolite catalyst to produce liquid hydrocarbons. Key words: Ga-HZSM-5; methane; acidic ion exchange; liquid hydrocarbons

Fullerene-Based Catalysts for Methane Activation

1994 ◽  
Vol 349 ◽  
Author(s):  
Hui-Jung Wu ◽  
Albert S. Hirschon ◽  
Ripudaman Malhotra ◽  
Robert B. Wilson
Keyword(s):  
Catalytic Activity ◽  
Aromatic Hydrocarbons ◽  
Methane Conversion ◽  
Thermal Conditions ◽  
Methane Activation ◽  
Minimal Amount ◽  
Fullerene Soot ◽  
Conversion Of Methane ◽  
Higher Hydrocarbons

ABSTRACTWe investigated fullerene based catalysts for the conversion of methane into higher hydrocarbons. Fullerene soot, CO2 activated soot, and extracted soot as well as a Norit-A carbon were examined as catalysts for methane activation. The soot was found to easily activate the C-H bond of methane, allowing methane conversion at lower temperatures (lower by 250°C) than found under purely thermal conditions. Furthermore, soot catalysis appears to produce a minimal amount of aromatic hydrocarbons. Extracted soot was found to have a lower selectivity for C2 hydrocarbons than the non-extracted soot, and the CO2 activation of the soot did not appear to dramatically alter the catalytic activity.

High catalytic activity for water oxidation based on nanostructured nickel phosphide precursors

2015 ◽  
Vol 51 (58) ◽  
pp. 11626-11629 ◽  
Author(s):  
Ali Han ◽  
Huanlin Chen ◽  
Zijun Sun ◽  
Jun Xu ◽  
Pingwu Du
Keyword(s):  
Catalytic Activity ◽  
Noble Metal ◽  
Water Oxidation ◽  
Oxidation Catalysis ◽  
High Catalytic Activity ◽  
Nickel Phosphide ◽  
Catalyst Precursor ◽  
Metal Free ◽  
Water Oxidation Catalysis ◽  
First Time

For the first time, noble-metal-free nickel phosphide (Ni2P) was used as an excellent catalyst precursor for water oxidation catalysis.

scholarly journals Active sites and mechanism of the direct conversion of methane and carbon dioxide to acetic acid over the zinc-modified H-ZSM-5 zeolite

2019 ◽  
Vol 9 (22) ◽  
pp. 6297-6307 ◽  
Author(s):  
Peng Zhang ◽  
Xuejing Yang ◽  
Xiuli Hou ◽  
Jianli Mi ◽  
Zhizhong Yuan ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Acetic Acid ◽  
Catalytic Activity ◽  
Active Sites ◽  
Direct Conversion ◽  
Conversion Of Methane ◽  
Zeolite P

The catalytic activity of the conversion of CH4 and CO2 on zinc modified H-ZSM-5 is strongly dependent on the structure of the active sites.

Heterogeneous copper-catalyzed synthesis of diaryl sulfones

2021 ◽  
Author(s):  
Xinchi Gong ◽  
Zhengqi Shen ◽  
Ganghu Wang ◽  
Lingling Qu ◽  
Chunyin Zhu
Keyword(s):  
Catalytic Activity ◽  
Copper Nanoparticles ◽  
High Catalytic Activity ◽  
First Time

A carbon-supported copper nanoparticles (Cu-NP) with high catalytic activity for the synthesis of diaryl sulfonens is reported. For the first time, this Cu-NP was proved to be able to effectively...

High-efficiency photo-oxidation of thioethers over C60@PCN-222 under air

2019 ◽  
Vol 7 (38) ◽  
pp. 22084-22091 ◽  
Author(s):  
Deng-Yue Zheng ◽  
En-Xuan Chen ◽  
Chun-Rong Ye ◽  
Xiao-Chun Huang
Keyword(s):  
Catalytic Activity ◽  
Photocatalytic Oxidation ◽  
High Efficiency ◽  
Photogenerated Electron ◽  
High Catalytic Activity ◽  
Electron Hole ◽  
Photo Oxidation ◽  
First Time

For the first time, fullerene (C60) was used to enhance the photogenerated electron–hole separation of MOFs as a catalyst and showed high catalytic activity in the photocatalytic oxidation of thioether in air.

scholarly journals Copper-Modified Zeolites and Silica for Conversion of Methane to Methanol

Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 545 ◽  
Author(s):  
Xueting Wang ◽  
Natalia Martin ◽  
Johan Nilsson ◽  
Stefan Carlson ◽  
Johan Gustafson ◽  
...  
Keyword(s):  
Active Sites ◽  
Copper Ions ◽  
Ambient Pressure ◽  
Direct Conversion ◽  
Minor Amount ◽  
Powder Materials ◽  
Methanol Production ◽  
Conversion Of Methane ◽  
First Time

Powder materials containing copper ions supported on ZSM-5 (Cu-Zeolite Socony Mobil-5) and SSZ-13 (Cu-Standard Oil synthesised zeolite-13), and predominantly CuO nanoparticles on amorphous SiO 2 were synthesised, characterised, wash-coated onto ceramic monoliths and, for the first time, compared as catalysts for direct conversion of methane to methanol (DCMM) at ambient pressure (1 atm) using O 2 , N 2 O and NO as oxidants. Methanol production was monitored and quantified using Fourier transform infrared spectroscopy. Methanol is formed over all monolith samples, though the formation is considerably higher for the copper-exchanged zeolites. Hence, copper ions are the main active sites for DCMM. The minor amount of methanol produced over the Cu/SiO 2 sample, however, suggests that zeolites are not the sole substrate that can host those active copper sites but also silica. Further, we present the first ambient pressure in situ infrared spectroscopic measurements revealing the formation and consumption of surface methoxy species, which are considered to be key intermediates in the DCMM reaction.

Enhanced catalytic activity of low-Pt content nanocatalysts supported on hollow carbon spheres for the ORR in alkaline media

MRS Advances ◽  
2020 ◽  
Vol 5 (57-58) ◽  
pp. 2961-2972
Author(s):  
P.C. Meléndez-González ◽  
E. Garza-Duran ◽  
J.C. Martínez-Loyola ◽  
P. Quintana-Owen ◽  
I.L. Alonso-Lemus ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Anion Exchange ◽  
Average Particle Size ◽  
Synthesis Method ◽  
Alkaline Media ◽  
High Catalytic Activity ◽  
Average Particle ◽  
Carbon Spheres ◽  
Hollow Carbon ◽  
Hollow Carbon Spheres

In this work, low-Pt content nanocatalysts (≈ 5 wt. %) supported on Hollow Carbon Spheres (HCS) were synthesized by two routes: i) colloidal conventional polyol, and ii) surfactant-free Bromide Anion Exchange (BAE). The nanocatalysts were labelled as Pt/HCS-P and Pt/HCS-B for polyol and BAE, respectively. The physicochemical characterization of the nanocatalysts showed that by following both methods, a good control of chemical composition was achieved, obtaining in addition well dispersed nanoparticles of less than 3 nm TEM average particle size (d) on the HCS. Pt/HCS-B contained more Pt0 species than Pt/HCS-P, an effect of the synthesis method. In addition, the structure of the HCS remains more ordered after BAE synthesis, compared to polyol. Regarding the catalytic activity for the Oxygen Reduction Reaction (ORR) in 0.5 M KOH, Pt/HCS-P and Pt/HCS-B showed a similar performance in terms of current density (j) at 0.9 V vs. RHE than the benchmark commercial 20 wt. % Pt/C. However, Pt/HCS-P and Pt/HCS-B demonstrated a 6 and 5-fold increase in mass catalytic activity compared to Pt/C, respectively. A positive effect of the high specific surface area of the HCS and its interactions with metal nanoparticles and electrolyte, which promoted the mass transfer, increased the performance of Pt/HCS-P and Pt/HCS-B. The high catalytic activity showed by Pt/HCS-B and Pt/HCS-P for the ORR, even with a low-Pt content, make them promising cathode nanocatalysts for Anion Exchange Membrane Fuel Cells (AEMFC).

Sign in / Sign up

Export Citation Format

Share Document