Friedel-Crafts Alkylation of o-xylene over V2O5 / ZrO2 Catalysts

2012 ◽  
Vol 11 (2) ◽  
pp. 1-16
Author(s):  
Sreejarani K Pillai ◽  
O Gheevarghese ◽  
I V Tleane
Keyword(s):  
Lewis Acidity ◽  
Bet Surface Area ◽  
High Yield ◽  
Impregnation Method ◽  
Lewis Acid Catalysts ◽  
Reaction Conditions ◽  
Cumene Cracking ◽  
Wet Impregnation ◽  
Nmr Techniques ◽  
Temperature Programmed

The present study has undertaken the Friedel-Crafts benzylation of aromatics over the V2O5/ZrO2 catalysts systems. Catalysts with different V2O5 content (0-15wt %) was prepared by wet impregnation method and characterized by XRD, BET surface area, FTIR and 5’V NMR techniques. The surface acidic properties were determined by temperature programmed desorption of NH3, cumene cracking and perylene adsorption. Under the optimized reaction conditions, these catalysts are found to be very effective and considerably more selective than the conventional homogeneous Lewis acid catalysts. The investigation of vanadia systems-catalyzed benzylation of o-xylene with benzyl chloride revealed that the catalytic activity and product selectivity are sensitive to the precise reaction parameters and can be related to the Lewis acidity of the systems. The reaction is found to be very clean and produces the desired monoalkylated product with high yield.

scholarly journals Nickel-based perovskite catalysts: synthesis and catalytic tests in the production of syngas

Cerâmica ◽  
2018 ◽  
Vol 64 (371) ◽  
pp. 436-442 ◽  
Author(s):  
E. O. Moraes Júnior ◽  
J. O. Leite ◽  
A. G. Santos ◽  
M. J. B. Souza ◽  
A. M. Garrido Pedrosa
Keyword(s):  
Impregnation Method ◽  
X Ray Diffraction ◽  
Organic Precursor ◽  
Wet Impregnation ◽  
Partial Oxidation Reaction ◽  
Conversion Level ◽  
Temperature Programmed ◽  
Perovskite Type ◽  
Wet Impregnation Method ◽  
H2 Selectivity

Abstract La1-xSrxNiO3 (x= 0.0, 0.3 or 0.7) perovskite-type oxides were synthesized using the modified proteic gel method and using collagen as an organic precursor. Catalysts of La1-xSrxNiO3/Al2O3 were obtained using the wet impregnation method. The synthesized catalysts were characterized by X-ray diffraction, surface area and temperature-programmed reduction. The catalysts were evaluated in the partial oxidation reaction of methane, and the levels of selectivity to CO, CO2, H2 and H2O were determined. Among the catalysts studied, the catalyst LaNiO3/Al2O3 had the highest methane conversion level (78%) and higher H2 selectivity (55%).

scholarly journals Effect of CO2 partial pressure on dry reforming of ethanol for hydrogen production

2018 ◽  
Vol 1 (1) ◽  
pp. 6-10
Author(s):  
Fahim Fayaz ◽  
Ahmad Ziad Sulaiman ◽  
Sharanjit Singh ◽  
Sweeta Akbari
Keyword(s):  
Partial Pressure ◽  
Fixed Bed ◽  
Dry Reforming ◽  
Fixed Bed Reactor ◽  
Bet Surface Area ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Co2 Partial Pressure ◽  
Temperature Programmed ◽  
Al2o3 Catalyst

The effect of CO2 partial pressure on ethanol dry reforming was evaluated over 5%Ce-10%Co/Al2O3 catalyst at = PCO2 = 20-50 kPa, PC2H5OH = 20 kPa, reaction temperature of 973 K under atmospheric pressure. The catalyst was prepared by using impregnation method and tested in a fixed-bed reactor. X-ray diffraction measurements studied the formation of Co3O4, spinel CoAl2O4 and CeO2, phases on surface of 5%Ce-10%Co/Al2O3 catalyst. CeO2, CoO and Co3O4 oxides were obtained during temperature–programmed calcination. Ce-promoted 10%Co/Al2O3 catalyst possessed high BET surface area of 137.35 m2 g-1. C2H5OH and CO2 conversions was improved with increasing CO2 partial pressure from 20-50 kPa whilst the optimal selectivity of H2 and CO was achieved at 50 kPa.

scholarly journals An Efficient Synthesis of 1,8-Dioxo-Octahydroxanthenes Derivatives Using Heterogeneous Ce-ZSM-11 Zeolite Catalyst

2018 ◽  
Vol 13 (3) ◽  
pp. 436 ◽  
Author(s):  
Rameshwar R. Magar ◽  
Ganesh T. Pawar ◽  
Sachin P. Gadekar ◽  
Machhindra Karbhari Lande
Keyword(s):  
Zeolite Catalyst ◽  
Bet Surface Area ◽  
High Yield ◽  
Efficient Synthesis ◽  
X Ray Diffraction ◽  
One Pot ◽  
Efficient Catalyst ◽  
Temperature Programmed ◽  
The One ◽  
Work Up

The Ce-ZSM-11 zeolite has been used as an efficient catalyst for the one pot synthesis of 1,8-dioxo-octahydroxanthene derivatives from aromatic aldehyde and 5,5-dimethyl-cyclohexane-1,3-dione under reflux condition. The catalyst was characterized by Powder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmer-Teller (BET) surface area analysis, and Temperature Programmed Desorption (TPD) techniques. This method provides several advantageous such as use of inexpensive catalyst, simple work-up procedure, high yield of desired product and reusability of catalyst. Copyright © 2018 BCREC Group. All rights reservedReceived: 5th January 2018; Revised: 25th May 2018; Accepted: 27th May 2018How to Cite: Magar, R.R., Pawar, G.T., Gadekar, S.P., Lande, M.K. (2018). An Efficient Synthesis of  1,8-Dioxo-Octahydroxanthenes Derivatives Using Heterogeneous Ce-ZSM-11 Zeolite Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 436-446 (doi:10.9767/bcrec.13.3.2062.436-446)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2062.436-446 

scholarly journals Oxidized Palladium Supported on Ceria Nanorods for Catalytic Aerobic Oxidation of Benzyl Alcohol to Benzaldehyde in Protic Solvents

Catalysts ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 847 ◽  
Author(s):  
Seyed Moeini ◽  
Chiara Battocchio ◽  
Stefano Casciardi ◽  
Igor Luisetto ◽  
Paolo Lupattelli ◽  
...  
Keyword(s):  
Benzyl Alcohol ◽  
Surface Area ◽  
Photoelectron Spectroscopy ◽  
Aerobic Oxidation ◽  
Bet Surface Area ◽  
Impregnation Method ◽  
X Ray ◽  
Protic Solvents ◽  
Oxidation Of Benzyl Alcohol ◽  
Temperature Programmed

In the present study, the catalytic activity of palladium oxide (PdOx) supported on ceria nanorods (CeO2-NR) for aerobic selective oxidation of benzyl alcohol (BnOH) to benzaldehyde (PhCHO) was evaluated. The CeO2-NR was synthesized hydrothermally and the Pd(NO3)2 was deposited by a wet impregnation method, followed by calcination to acquire PdOx/CeO2-NR. The catalysts were characterized by X-ray diffraction (XRD), temperature programmed reduction (TPR), transmission electron microscopy (TEM), Brunauer–Emmet–Teller (BET) surface area analysis, and X-ray photoelectron spectroscopy (XPS). In addition, the TPR-reduced PdOx/CeO2-NR (PdOx/CeO2-NR-Red) was studied by XRD, BET, and XPS. Characterizations showed the formation of CeO2-NR with (111) exposed plane and relatively high BET surface area. PdOx (x > 1) was detected to be the major oxide species on the PdOx/CeO2-NR. The activities of the catalysts in BnOH oxidation were evaluated using air, as an environmentally friendly oxidant, and various solvents. Effects of temperature, solvent nature and palladium oxidation state were investigated. The PdOx/CeO2-NR showed remarkable activity when protic solvents were utilized. The best result was achieved using PdOx/CeO2-NR and boiling ethanol as solvent, leading to 93% BnOH conversion and 96% selectivity toward PhCHO. A mechanistic hypothesis for BnOH oxidation with PdOx/CeO2-NR in ethanol is presented.

Study on CO2 Hydrogenation to Ethylene with Iron-Based Catalyst

2013 ◽  
Vol 791-793 ◽  
pp. 112-115
Author(s):  
Chun Yan Su ◽  
Jian Qun Tan ◽  
Cheng Xue Wang
Keyword(s):  
Carbon Dioxide ◽  
Temperature Programmed Desorption ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Active Components ◽  
Reaction Conditions ◽  
Reaction Pressure ◽  
Carbon Dioxide Hydrogenation ◽  
Iron Based ◽  
Temperature Programmed

Carbon dioxide hydrogenation to ethylene was investigated on Fe-Cu-K-Ce loading catalysts. These catalysts were prepared by impregnation method, and studied on the CO2conversion and the selectivity of ethylene. The proper carrier was obtained comparing with their catalytic activity. The loading contents of active components on carriers and reaction conditions were studied. Results show that the MgO-ZSM-5 are the best carrier, the content of Fe at 15% and the molar ratio of Fe: Cu: K: Ce with 100: 20: 8: 8 is better under the condition of reaction temperature and reaction pressure are 623K and 1.0Mpa respectively with CO2conversion of more than 60% and the selectivity of ethylene of more than 20%. The catalysts were characterized by CO2temperature-programmed desorption (CO2-TPD).

Catalytic activity of CaO-based catalyst in transesterification of microalgae oil with methanol

2018 ◽  
Vol 30 (1) ◽  
pp. 176-187 ◽  
Author(s):  
Emine E Çakırca ◽  
Gizem N Tekin ◽  
Oğuzhan İlgen ◽  
Ayşe N Akın
Keyword(s):  
Fatty Acid Methyl Esters ◽  
Methyl Esters ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Reaction Conditions ◽  
Wet Impregnation ◽  
Work Activities ◽  
Catalyst Type ◽  
Microalgae Oil ◽  
Wet Impregnation Method

In this work, activities of modified dolomite catalysts using calcium acetate in the heterogeneously catalyzed transesterification of microalgae oil with methanol were investigated. Modified catalysts were prepared via wet impregnation method and calcined 850°C for 2 h. Reaction conditions were examined as the catalyst type, amount of catalyst, methanol/microalgae oil molar ratio, and reusability of the catalyst using the dolomite and modified dolomite catalysts. When investigated reusability of the modified dolomite catalyst in the transesterification of microalgae oil with methanol, catalyst was reused three times with a small loss of activity. After fourth run, reused catalyst was calcined again and got similar activity to the first run. The highest fatty acid methyl esters (FAME) yield of 90% was obtained when the reaction was performed with methanol/microalgae oil molar ratio of 6:1, catalyst amount of 3%, and reaction temperature at 65°C for 3 h by using the 30% CaO/dolomite catalyst.

scholarly journals SYNTHESIS, CHARACTERIZATION, AND APPLICATION OF ZnO/ZSM-5 AS CATALYST IN THE CRACKING PROCESS OF PALM METHYL ESTERS

2021 ◽  
pp. 1-8
Author(s):  
Nina Haryani ◽  
Taslim Taslim ◽  
Irvan ◽  
Renita Manurung ◽  
Rondang Tambun
Keyword(s):  
Alternative Fuels ◽  
Methyl Esters ◽  
Environmentally Friendly ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Wet Impregnation ◽  
X Ray ◽  
Temperature Programmed ◽  
Cracking Process ◽  
Adsorption Desorption

Biofuels as environmentally friendly alternative fuels such as biogasoline, biokerosene and others are generally obtained through a cracking process and take place more effectively to attend a catalyst. In this study, the synthesis of ZnO/ZSM-5 aims to obtain a catalyst that can be used in the cracking process of Palm Methyl Esters (PME) into hydrocarbon fuels especially biogasoline. This catalyst is environmentally friendly, easy to separate, has good selectivity, and can increase the conversion of cracking products. The wet impregnation method followed by drying and calcination is the method used to synthesize the catalyst. Furthermore, several analyzes were carried out to determine the characteristics of the catalyst. The analysis is the Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX), X-Ray Diffraction (XRD), N2 adsorption-desorption with BET-BJH, Temperature Programmed Desorption-NH3 (TPD-NH3) and the Temperature Programmed Reduction (TPR). Based on synthesis results obtained ZnO/ZSM-5 catalyst with ZnO content of 11.77 wt%, 13.61 wt% and 18.22 wt%. The use of this catalyst in the cracking process can result in the conversion of liquid fuel by 88.57%, heavy hydrocarbon (8.57%) and gas product (2.86%).

Ni/x%Nb2O5/Al2O3 Catalysts Prepared via Coprecipitation-Wet Impregnation Method for Methane Steam Reforming

2020 ◽  
Vol 9 (1) ◽  
pp. 80-89
Author(s):  
Juliana F. Gonçalves ◽  
Mariana M.V.M. Souza
Keyword(s):  
Steam Reforming ◽  
Methane Conversion ◽  
Coke Formation ◽  
Methane Steam Reforming ◽  
Impregnation Method ◽  
Wet Impregnation ◽  
X Ray ◽  
Methane Steam ◽  
Temperature Programmed ◽  
Wet Impregnation Method

Background: Hydrogen has been considered the energy source of the future and one of the processes for its production is the methane steam reforming. The catalyst used industrially is Ni/Al2O3 and the addition of promoter oxides can be an alternative to improve the performance of this catalyst, which suffers from coke formation and sintering. Objective: Evaluate the role of niobia on catalytic activity and stability. Methods: Ni/x%Nb2O5/Al2O3 (x = 5, 10 and 20) catalysts were synthesized via coprecipitation-wet impregnation method and characterized by X-ray fluorescence (XRF), N2 adsorption-desorption, X-ray diffraction (XRD), temperature- programmed reduction (TPR), temperature-programmed desorption of ammonia (TPD-NH3), etc. Finally, the catalysts were tested for methane steam reforming reaction. Results: All niobia-doped catalysts presented similar values of methane conversion and when comparing with Ni-Al, the addition of niobia slightly improved the methane conversion. In the stability test at 800oC, all doped and non-doped catalysts did not deactivate during the 24 h of reaction. Conclusion: The addition of 10 and 20 wt.% of niobia had a significant promoter effect over Ni/Al2O3 catalyst in terms of activity and stability at 800 oC and the sample with 20 wt.% of niobia presented lower coke formation.

scholarly journals Improved CO-PROX Performance of CuO/CeO2 Catalysts by Using Nanometric Ceria as Support

Catalysts ◽  
2018 ◽  
Vol 8 (5) ◽  
pp. 209 ◽  
Author(s):  
Almerinda Di Benedetto ◽  
Gianluca Landi ◽  
Luciana Lisi
Keyword(s):  
High Activity ◽  
Catalytic Performance ◽  
Oxidation Of Co ◽  
High Concentration ◽  
Reaction Conditions ◽  
Wet Impregnation ◽  
Preferential Oxidation Of Co ◽  
Icp Ms ◽  
Copper Sites ◽  
Temperature Programmed

Despite of the huge number of papers about the catalytic preferential oxidation of CO (CO-PROX) for the purification of H2 streams, there is still a need for more effective catalysts in order to reduce the large required catalyst volume of CO-PROX unity. In this work, large surface area nanometric ceria was used as support for CuO/CeO2 catalysts with CuO load up to 10 wt % easily dispersed by wet impregnation. Catalysts were characterized by ICP-MS, XRD, SEM/EDS, N2 physisorption, H2 temperature programmed reduction (TPR), and CO2 temperature programmed desorption (TPD) and tested under different reaction conditions (including under feed containing inhibiting species such as CO2 and H2O). Catalytic tests revealed that our samples show high activity and selectivity even under stringent reaction conditions; moreover, they result among the most active catalysts when compared to those reported in the scientific literature. The high activity can be related to the enhanced amount of highly dispersed copper sites in strong interaction with ceria related to the nature of the nanometric support, as evidenced by the characterization techniques. Despite the high concentration of active copper sites, catalytic performance is limited by CO2 desorption from ceria in the neighborhood of copper sites, which prevents a further improvement. This suggests that new catalyst formulations should also provide a lower affinity towards CO2.

scholarly journals Structured Pd/γ-Al2O3 Prepared by Washcoated Deposition on a Ceramic Honeycomb for Compressed Natural Gas Applications

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Małgorzata Adamowska ◽  
Patrick Da Costa
Keyword(s):  
Bet Surface Area ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Sem Images ◽  
Alumina Layer ◽  
Incipient Wetness ◽  
Temperature Programmed ◽  
The One ◽  
Ceramic Honeycomb ◽  
Monolith Catalyst

The preparation of a coating procedure was studied, from the washcoating with γ-alumina to the deposition of palladium by excess solvent or incipient wetness impregnation. The powder and the washcoat layers were studied by different characterisation techniques such as SEM, BET surface area, and XRD. Vibration-resistance and heat-resistance were also evaluated. It was shown that the alumina layer is quite well deposited on the channel walls (SEM images). However, a detachment of the washcoat layer was observed after ultrasound treatment. It was proved that the monolith Pd impregnation method by incipient wetness impregnation is more efficient. The presence of palladium was confirmed using HRTEM, the palladium was present under the Pd (II) oxidation state, and the size of PdO particles varies between 2.5 and 3.1 nm. The catalytic properties of the monolith catalyst were carried out using temperature programmed surface reaction (TPSR). The efficiency of the procedure of the monolith catalyst preparation was confirmed by comparing the activity of the prepared catalyst with the one of a model catalyst.

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