scholarly journals One-Pot Synthesis of CeO2 Modified SBA-15 With No Pore Clogging for NO Reduction by CO

2021 ◽  
Vol 2 ◽  
Author(s):  
Kaili Ma ◽  
Hongliang Zhang ◽  
Changjin Tang ◽  
Lin Dong
Keyword(s):  
Great Influence ◽  
Catalytic Performance ◽  
Mineral Acid ◽  
Silica Matrix ◽  
Soft Template ◽  
Impregnation Method ◽  
One Pot ◽  
X Ray ◽  
One Pot Synthesis ◽  
Pore Clogging

CeO2 modified SBA-15 composites have been prepared by adding cerium precursor (Ce(NO3)3·6H2O) directly into the mixture of soft template (P123), silica precursor (TEOS) and urea aqueous solution but without mineral acid. The products were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), N2 physisorption and transmission electron microscopy (TEM). Results indicated that ceria were successfully grafted onto mesoporous silica matrix and no pore clogging was observed. Both ceria content and mesoporous ordering of the final products were found to depend on urea amount. Compared to CeO2/SBA-15 from conventional impregnation method, the one-pot synthesis not only showed simple and green operation, but also superior catalytic performance in NO+CO reaction after loaded with CuO. It was revealed that both the presence and location of ceria had great influence on the reducibility of CuO, and the catalytic performances were intimately related to the redox properties of crystalline CuO. That is, higher NO conversion and N2 selectivity were achieved over catalyst with easier reduction of crystalline CuO.

Structural/Texture Evolution During Facile Substitution of Ni into ZSM-5 Nanostructure vs. its Impregnation Dispersion Used in Selective Transformation of Methanol to Ethylene and Propylene

2020 ◽  
Vol 23 ◽  
Author(s):  
Parisa Sadeghpour ◽  
Mohammad Haghighi ◽  
Mehrdad Esmaeili
Keyword(s):  
High Temperature ◽  
Physicochemical Properties ◽  
Active Sites ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Light Olefins ◽  
Isomorphous Substitution ◽  
Impregnation Method ◽  
Hydrothermal Temperature ◽  
X Ray

Aim and Objective: Effect of two different modification methods for introducing Ni into ZSM-5 framework was investigated under high temperature synthesis conditions. The nickel successfully introduced into the MFI structures at different crystallization conditions to enhance the physicochemical properties and catalytic performance. Materials and Methods: A series of impregnated Ni/ZSM-5 and isomorphous substituted NiZSM-5 nanostructure catalysts were prepared hydrothermally at different high temperatures and within short times. X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray (EDX), Brunner, Emmett and Teller-Barrett, Joyner and Halenda (BET-BJH), Fourier transform infrared (FTIR) and Temperature-programmed desorption of ammonia (TPDNH3) were applied to investigate the physicochemical properties. Results: Although all the catalysts showed pure silica MFI–type nanosheets and coffin-like morphology, using the isomorphous substitution for Ni incorporation into the ZSM-5 framework led to the formation of materials with lower crystallinity, higher pore volume and stronger acidity compared to using impregnation method. Moreover, it was found that raising the hydrothermal temperature increased the crystallinity and enhanced more uniform incorporation of Ni atoms in the crystalline structure of catalysts. TPD-NH3 analysis demonstrated that high crystallization temperature and short crystallization time of NiZSM-5(350-0.5) resulted in fewer weak acid sites and medium acid strength. The MTO catalytic performance was tested in a fixed bed reactor at 460ºC and GHSV=10500 cm3 /gcat.h. A slightly different reaction pathway was proposed for the production of light olefins over impregnated Ni/ZSM-5 catalysts based on the role of NiO species. The enhanced methanol conversion for isomorphous substituted NiZSM-5 catalysts could be related to the most accessible active sites located inside the pores. Conclusion: The impregnated Ni/ZSM-5 catalyst prepared at low hydrothermal temperature showed the best catalytic performance, while the isomorphous substituted NiZSM-5 prepared at high temperature was found to be the active molecular sieve regarding the stability performance.

scholarly journals Influence of Sulfur-Containing Sodium Salt Poisoned V2O5–WO3/TiO2 Catalysts on SO2–SO3 Conversion and NO Removal

Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 541 ◽  
Author(s):  
Haiping Xiao ◽  
Chaozong Dou ◽  
Hao Shi ◽  
Jinlin Ge ◽  
Li Cai
Keyword(s):  
Photoelectron Spectroscopy ◽  
No Reduction ◽  
Catalytic Performance ◽  
Acid Sites ◽  
Impregnation Method ◽  
So2 Oxidation ◽  
Sodium Salts ◽  
X Ray ◽  
Temperature Programmed ◽  
Physical Features

A series of poisoned catalysts with various forms and contents of sodium salts (Na2SO4 and Na2S2O7) were prepared using the wet impregnation method. The influence of sodium salts poisoned catalysts on SO2 oxidation and NO reduction was investigated. The chemical and physical features of the catalysts were characterized via NH3-temperature programmed desorption (NH3-TPD), H2-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that sodium salts poisoned catalysts led to a decrease in the denitration efficiency. The 3.6% Na2SO4 poisoned catalyst was the most severely deactivated with denitration efficiency of only 50.97% at 350 °C. The introduction of SO42− and S2O72− created new Brønsted acid sites, which facilitated the adsorption of NH3 and NO reduction. The sodium salts poisoned catalysts significantly increased the conversion of SO2–SO3. 3.6%Na2S2O7 poisoned catalyst had the strongest effect on SO2 oxidation and the catalyst achieved a maximum SO2–SO3-conversion of 1.44% at 410 °C. Characterization results showed sodium salts poisoned catalysts consumed the active ingredient and lowered the V4+/V5+ ratio, which suppressed catalytic performance. However, they increased the content of chemically adsorbed oxygen and the strength of V5+=O bonds, which promoted SO2 oxidation.

scholarly journals Synthesis of new bimetallic phosphate (Al/Ag3PO4) and study for its Catalytic performance in the synthesis of 1,2-dihydro-l-phenyl-3H-naphth [1,2-e]-[1,3] oxazin-3-one derivatives

2021 ◽  
Vol 11 (3) ◽  
pp. 215
Author(s):  
Achraf El Hallaoui ◽  
Tourya Ghailane ◽  
Soukaina Chehab ◽  
Youssef Merroun ◽  
Rachida Ghailane ◽  
...  
Keyword(s):  
Reaction Times ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Silver Sulfate ◽  
Triple Super Phosphate ◽  
Aryl Aldehyde ◽  
Ft Ir ◽  
First Time

<p>This work aims to prepare a new bimetallic phosphate catalyst using a new simple and effective method. This new catalyst was ready for the first time by a modification of Triple Super Phosphate (TSP) fertilizer with silver sulfate (AgSO<sub>4</sub>), followed by the impregnation of the aluminum atoms using aluminum nitrate (Al(NO<sub>3</sub>)<sub>3</sub>). The use of Al/Ag<sub>3</sub>PO<sub>4</sub>, for the first time as a heterogeneous catalyst in organic chemistry, offers a new, efficient, and green pathway for synthesizing 1,2-dihydro-l-phenyl-3H-naphth[1,2-e]-[1,3]oxazin-3-one derivatives by one-pot three-component cyclocondensation of b-naphthol, aryl aldehyde, and urea. The structure and the morphology of the prepared catalyst were characterized by spectroscopic methods such as X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), and dispersive X-ray spectrometry coupled with a scanning electron microscope (EDX-SEM). In addition, the optimization of the reaction parameters was carried out considering the effect of catalyst amount, the temperature, and the solvent. The procedure described herein allowed a comfortable preparation of oxazine derivatives with excellent yields, short reaction times, and in the absence of organic solvent.</p>

scholarly journals Funktionalisierte tripod-Liganden mit Neopentan-Grundgerüst: Umsetzung von HOCH2C(CH2PR2)3 mit Elektrophilen / Functionalized tripod-Ligands with N eopentane Fram ew ork: R eaction of HOCH2C(CH2PR2)3 with Electrophiles

1995 ◽  
Vol 50 (9) ◽  
pp. 1287-1306 ◽  
Author(s):  
Thomas Seitz ◽  
Alexander Asam ◽  
Gottfried Hüttner ◽  
Olaf Walter ◽  
Laszlo Zsolnai
Keyword(s):  
Hydroxy Group ◽  
Analytical Techniques ◽  
One Pot ◽  
X Ray ◽  
One Pot Synthesis ◽  
Tripod Ligands ◽  
Esterification Reactions ◽  
New Compounds

AbstractSeveral ways to functionalize hydroxy-tripod-ligands (HOCH2C(CH2PR2)3) by activation with electrophiles are presented. The use of carboxylic halides and anhydrides is shown to be generally successful for esterification reactions in a one-pot synthesis starting from the oxetanes O(CH2)2C(CH2PR2)2. Facial coordinaton of the related esters towards iron(II) and molybdenum(O) can be achieved depending on the nature of the phosphane donor groups. If methyliodide or trimethylsilylchloride are used as electrophiles in order to functionalize the hydroxy group in HOCH2C(CH2PR2)3, it is necessary to proctect the phosphane groups by formation of the tris-borane adduct. All new compounds have been fully characterized by the usual analytical techniques as well as by X-ray analyses on selected examples.

scholarly journals FeNiCeOx ternary catalyst prepared by ultrasonic impregnation method for diclofenac removal in Fenton-like system

2019 ◽  
Vol 79 (9) ◽  
pp. 1675-1684 ◽  
Author(s):  
Guang Xian ◽  
Nan Zhang ◽  
Guangming Zhang ◽  
Yi Zhang ◽  
Zhiguo Zou
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Hot Spot ◽  
Catalytic Performance ◽  
Synthesis Process ◽  
Impregnation Method ◽  
Lattice Contraction ◽  
X Ray ◽  
Ultrasonic Synthesis ◽  
Cavitation Effect

Abstract FeNiCeOx was firstly prepared by ultrasonic impregnation method and used to remove diclofenac in a Fenton-like system. The catalytic activity was improved successfully by doping Ni into FeCeOx. The diclofenac removal efficiency reached 97.9% after 30 min reaction. The surface morphology and properties of FeNiCeOx were characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Raman and X-ray photoelectron spectroscopy (XPS) analyses. FeNiCeOx in this paper had larger specific surface area than those prepared by other methods, which was attributed to the cavitation effect and hot-spot effect during the ultrasonic synthesis process. Low crystallinity of Fe2O3 and NiO showed by characterization could lead to high interaction of Fe and Ni ions with support of CeO2. They substituted Ce in CeO2, caused lattice contraction and formed more oxygen vacancies, which favoured the catalytic reaction. Meanwhile, Fe and Ce ions both had redox cycles of Fe3+/Fe2+ and Ce4+/Ce3+, which facilitated the electron transfer in the reaction. The synergistic effect among Fe, Ni and Ce might lead to better catalytic performance of FeNiCeOx than any binary metal oxides constituted from the above three elements. Finally, the potential mechanism of diclofenac removal in FeNiCeOx-H2O2 system is proposed.

scholarly journals Preparation of Ni-IL/SiO2 and its catalytic performance for one-pot sequential synthesis of 2-propylheptanol from n-valeraldehyde

RSC Advances ◽  
2020 ◽  
Vol 10 (47) ◽  
pp. 28100-28105
Author(s):  
Hualiang An ◽  
Di Wang ◽  
Shuang Miao ◽  
Qiusheng Yang ◽  
Xinqiang Zhao ◽  
...  
Keyword(s):  
Catalytic Performance ◽  
One Pot ◽  
One Pot Synthesis ◽  
The One ◽  
Excellent Catalytic Performance

The prepared Ni-IL/SiO2 catalyst exhibits an excellent catalytic performance in the one-pot synthesis of 2-propylheptanol: the yield of 2-propylheptanol attained 75.4%.

One-pot synthesis of carbon-coated Fe3O4 nanoparticles with tunable size for production of gasoline fuels

2018 ◽  
Vol 42 (13) ◽  
pp. 10861-10867 ◽  
Author(s):  
Junling Tu ◽  
Jiaojiao Yuan ◽  
Shimin Kang ◽  
Yongjun Xu ◽  
Tiejun Wang
Keyword(s):  
Fe3o4 Nanoparticles ◽  
Direct Synthesis ◽  
Catalytic Performance ◽  
One Pot ◽  
One Pot Synthesis ◽  
Carbon Coated ◽  
Excellent Catalytic Performance

Fe3O4@C nanoparticles with tunable size exhibit excellent catalytic performance in the direct synthesis of gasoline fuels.

scholarly journals Preparation, characterization and catalytic performance of Pt supported on porous carbonaceous materials in the oxidation of toluene as a volatile organic compound

2019 ◽  
Vol 45 ◽  
pp. 146867831988793
Author(s):  
Niloofar Atashi ◽  
Mohammad Hasan Peyrovi ◽  
Nastaran Parsafard
Keyword(s):  
Carbon Nanotube ◽  
Organic Compound ◽  
Power Law ◽  
Volatile Organic Compound ◽  
Inductively Coupled Plasma ◽  
Textural Properties ◽  
Catalytic Performance ◽  
Impregnation Method ◽  
X Ray ◽  
Volatile Organic

Platinum-carbonaceous catalysts were prepared by the wet impregnation method and tested for catalytic oxidation of toluene as a volatile organic compound. The textural properties of the constructed catalysts were considered by X-ray diffraction, X-ray fluorescence, inductively coupled plasma – optical emission spectroscopy, Fourier transform infrared, scanning electron microscope and N2 adsorption–desorption analysis. The catalytic assessments showed that the best activity (>99%) and high stability and selectivity to CO2 (>99%) are related to platinum-supported carbon nanotube. The curves of the conversion and selectivity demonstrate that the performance of catalysts to eliminate the volatile organic compound and turn it into CO2 conforms to the following descending order: platinum-supported carbon nanotube >platinum-supported graphene >platinum-supported activated carbon >platinum-supported carbon nanofibre. The kinetic of toluene oxidation has been evaluated as a function of toluene and oxygen partial pressures in different temperatures. Two kinetic models (Power Law and Mars–van Krevelen mechanisms) were applied to the reaction and compared with the experimental data. Mars–van Krevelen model is more appropriate than the Power Law model for this reaction as Mars–van Krevelen model showed better prediction of the behaviour of the reaction.

Preparation of a ternary Pd–Rh–P amorphous alloy and its catalytic performance in selective hydrogenation of alkynes

2014 ◽  
Vol 4 (7) ◽  
pp. 1920-1924 ◽  
Author(s):  
Mengrui Ren ◽  
Changming Li ◽  
Jiale Chen ◽  
Min Wei ◽  
Shuxian Shi
Keyword(s):  
Amorphous Alloy ◽  
Selective Hydrogenation ◽  
Synthesis Method ◽  
Catalytic Performance ◽  
Alloy Nanoparticles ◽  
One Pot ◽  
One Pot Synthesis ◽  
Catalytic Behaviour

Palladium–rhodium–phosphorus amorphous alloy nanoparticles were prepared via a facile one-pot synthesis method, exhibiting excellent catalytic behaviour in selective hydrogenation of alkynes.

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