scholarly journals PROMETHEUS: A Copper-Based Polymetallic Catalyst for Automotive Applications. Part II: Catalytic Efficiency an Endurance as Compared with Original Catalysts

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2226
Author(s):  
Iakovos Yakoumis ◽  
Εkaterini Polyzou ◽  
Anastasia Maria Moschovi

PROMETHEUS catalyst, a copper-based polymetallic nano-catalyst has been proven to be suitable for automotive emission control applications. This novel catalyst consists of copper, palladium and rhodium nanoparticles as active phases, impregnated on an inorganic oxide substrate, CeO2/ZrO2 (75%, 25%). The aim of PROMETHEUS catalyst’s development is the substitution of a significant amount (85%) of Platinum Group Metals (PGMs) with copper nanoparticles while, at the same time, presenting high catalytic efficiency with respect to the commercial catalysts. In this work, an extensive investigation of the catalytic activity of full scale PROMETHEUS fresh and aged catalyst deposited on ceramic cordierites is presented and discussed. The catalytic activity was tested on an Synthetic Gas Bench (SGB) towards the oxidation of CO and CH4 and the reduction of NO. The loading of the washcoat was 2 wt% (metal content) on Cu, Pd, Rh with the corresponding metal ratio at 21:7:1. The concentration of the full-scale monolithic catalysts to be 0.032% total PGM loading for meeting Euro III standard and 0.089% for meeting Euro IV to Euro VIb standards. The catalytic activity of all catalysts was tested both in rich-burn (λ = 0.99) and lean-burn conditions (λ = 1.03).

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohammad Hossein Abdollahi-Basir ◽  
Boshra Mirhosseini-Eshkevari ◽  
Farzad Zamani ◽  
Mohammad Ali Ghasemzadeh

AbstractA one-pot three component reaction of benzaldehydes, 1H-tetrazole-5-amine, and 3-cyanoacetyl indole in the presence of a new hexamethylenetetramine-based ionic liquid/MIL-101(Cr) metal–organic framework as a recyclable catalyst was explored. This novel catalyst, which was fully characterized by XRD, FE-SEM, EDX, FT-IR, TGA, BET, and TEM exhibited outstanding catalytic activity for the preparation of a range of pharmaceutically important tetrazolo[1,5-a]pyrimidine-6-carbonitriles with good to excellent yields in short reaction time.


Author(s):  
Mi Yoo ◽  
Eunji Kang ◽  
Hyuk Choi ◽  
Hyunwoo Ha ◽  
Han Seul Choi ◽  
...  

Single-atoms Single-atoms (SAs) with atomically coordinated reaction centers are considered the next generation catalyst that can reveal exceptional catalytic efficiency. However, the general concern about thermodynamic vulnerabilities of the SAs...


2004 ◽  
Vol 30/31 ◽  
pp. 27-30 ◽  
Author(s):  
F. Klingstedt ◽  
K. Eränen ◽  
L.-E. Lindfors ◽  
S. Andersson ◽  
L. Cider ◽  
...  

RSC Advances ◽  
2017 ◽  
Vol 7 (67) ◽  
pp. 42000-42012 ◽  
Author(s):  
Pramod K. Sahu

A green synthesis of hydrotalcite (a double layered catalyst) by a grinding method using Al/Mg molar ratios of 1.0–3.0 at room temperature is described.


2010 ◽  
Vol 24 (31) ◽  
pp. 6115-6127 ◽  
Author(s):  
MARYAMOSSADAT BOZORGTABAR ◽  
MEHDI SALEHI ◽  
MOHAMMADREZA RAHIMIPOUR ◽  
MOHAMMADREZA JAFARPOUR

Titanium dioxide coatings were deposited by utilizing atmospheric plasma-spraying system. The agglomerated P25/20 nano-powder and different spraying parameters (e.g., Argon flow rate and spray distance) were used to determine their influences on the microstructure, crystalline structure, photo-absorption, and photo-catalytic performance of the coatings. The microstructure and phases of as-sprayed TiO 2 coatings were characterized by scanning electron microscope SEM and X-ray diffraction, respectively. Surface characteristics were investigated by Fourier Transform Infrared. Photo-catalytic efficiency of the elaborated samples was also determined in an environmental test chamber set-up and evaluated from the conversion rate of ethanol. The photo-absorption was determined by UV–Vis spectrophotometer. The as-sprayed TiO2 coating was photo-catalytically reactive for the degradation of ethanol. The photo-catalytic activity was influenced by spray conditions. It is found that the photo-catalytic activity is significantly influenced by anatase content, surface area, and surface state. The results showed that the argon flow rate has an influence on the microstructure, anatase content, and photo-catalytic activity of the TiO 2 coatings.


2012 ◽  
Vol 549 ◽  
pp. 445-448
Author(s):  
Li Dan Fan ◽  
Gang Qin ◽  
Xin Xin Cao ◽  
Shao Kui Cao

A novel catalyst for the copolymerization of CO2 and cyclohexene oxide(CHO) was prepared by using BTE and ZnCl2. The zinc complex showed catalytic activity for the copolymerization. The obtained copolymer was characterized by IR and NMR. Effect of reaction time on copolymerization was investigated.


2019 ◽  
Vol 6 (2) ◽  
pp. 171-176
Author(s):  
Rajasekhar Dodda ◽  
Sampak Samanta ◽  
Matthew Su ◽  
John Cong-Gui Zhao

Background: While proline can catalyze the asymmetric direct aldol reactions, its catalytic activity and catalyst turnover are both low. To improve the catalytic efficiency, many prolinebased organocatalysts have been developed. In this regard, prolinamide-based bifunctional catalysts have been demonstrated by us and others to be highly efficient catalysts for the direct aldol reactions. Results: Using the β-acetamido- and β-tosylamidoprolinamide catalysts, the highly enantio- and diastereoselective direct aldol reactions between enolizable ketones and aldehydes were achieved (up to >99% ee, 98:2 dr). A low catalyst loading of only 2-5 mol % of the β-tosylamidoprolinamide catalyst was needed to obtain the desired aldol products in good to high yields and high stereoselectivities. Methods: By carefully adjusting the hydrogen bonding ability of the remote β-amide hydrogen of the 1,2-diamine-based prolinamide bifunctional catalysts, the catalytic activity and the asymmetric induction of these catalysts were significantly improved for the direct aldol reaction between aldehydes and enolizable ketones. Conclusion: Some highly efficient 1,2-diamine-based bifunctional prolinamide catalysts have been developed through probing the remote β-amide hydrogen for its hydrogen bonding capability. These catalysts are easy to synthesize and high enantioselectivities may be achieved at very low catalyst loadings.


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