Catalytic Activity of Bimetallic Cu-Ag/MgO-SiO2 Toward the Conversion of Ethanol to 1,3-Butadiene

2016 ◽  
Vol 14 (5) ◽  
pp. 945-954 ◽  
Author(s):  
Anamol Tripathi ◽  
Kajornsak Faungnawakij ◽  
Apirat Laobuthee ◽  
Suttichai Assabumrungrat ◽  
Navadol Laosiripojna
Keyword(s):  
Chemical Properties ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Monometallic Catalysts ◽  
Reaction Test ◽  
Spent Catalysts ◽  
Temperature Programmed ◽  
Preparation Techniques ◽  
Microwave Assisted Method

Abstract In the present work, the catalytic conversion of ethanol to 1,3-butadiene (1,3-BD) was studied over monometallic of Cu and Ag, and bimetallic Cu-Ag supported on MgO-SiO2 (with MgO/SiO2 ratio of 2.0) under the temperature range from 250 to 325 °C. All catalysts were prepared by 4 different techniques including (i) conventional impregnation, (ii) microwave-assisted method, (iii) polyvinyl alcohol/sodium borohydride (PVA/NaBH4) assisted method, and (iv) benzoxaxine-assisted method to elucidate the effect of catalyst preparation method on their catalytic performance. All fresh and spent catalysts were also characterized by X-ray diffraction (XRD), N2 adsorption and Temperature-programmed reduction (TPR) techniques to understand the relation between their physical/chemical properties and catalytic performance. From the reaction test, it was found that 5 %Ag/MgO-SiO2 showed greater activity towards 1,3-BD production than 5 %Cu/MgO-SiO2; nevertheless, higher deactivation after 6 h of operation was observed from 5 %Ag/MgO-SiO2. Importantly, this study revealed that bimetallic 2.5 %Cu-2.5 %Ag/MgO-SiO2 enhanced significantly higher activity and stability towards the reaction than monometallic catalysts. In addition, 2.5 %Cu-2.5 %Ag/MgO-SiO2 prepared by benzoxaxine-assisted method enhanced significantly higher reaction activity and stability than other preparation techniques, from which 1,3-BD yield of 46.40 % after 6 h of operation can be achieved. From the characterization, the good activity of this catalyst is mainly due to the dispersion improvement of metal over MgO-SiO2 support.

scholarly journals Generalized Methodology for Inserting Metal Heteroatoms into the Layered Zeolite Precursor RUB-36 by Interlayer Expansion

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 530 ◽  
Author(s):  
Chaoqun Bian ◽  
Xiao Wang ◽  
Lan Yu ◽  
Fen Zhang ◽  
Jie Zhang ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Inductively Coupled Plasma ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
Zeolite Sample ◽  
X Ray ◽  
Inductively Coupled ◽  
Temperature Programmed ◽  
First Time ◽  
N2 Sorption

The incorporation of metal heteroatoms into zeolites is an effective modification strategy for enhancing their catalytic performance. Herein, for the first time we report a generalized methodology for inserting metal heteroatoms (such as Sn, Fe, Zn, and Co) into the layered zeolite precursor RUB-36 via interlayer expansion by using the corresponding metal acetylacetate salt. Through this generalized methodology, Sn-JHP-1, Fe-JHP-1, Zn-JHP-1 and Co-JHP-1 zeolites could be successfully prepared by the reaction of RUB-36 and corresponding metal acetylacetate salt at 180 °C for 24 h in the presence of HCl solution. As a typical example, Sn-JHP-1 and calcined Sn-JHP-1 (Sn-JHP-2) zeolite is well characterized by the X-ray diffraction (XRD), diffuse reflectance ultraviolet-visible (UV-Vis), inductively coupled plasma (ICP), N2 sorption, temperature-programmed-desorption of ammonia (NH3-TPD) and X-ray photoelectron spectroscopy (XPS) techniques, which confirm the expansion of adjacent interlayers and thus the incorporation of isolated Sn sites within the zeolite structure. Notably, the obtained Sn-JHP-2 zeolite sample shows enhanced catalytic performance in the conversion of glucose to levulinic acid (LA) reaction.

Investigating the properties and performance of 3A molecular sieves as an adsorbent to prevent coke formation in olefin dehydration process

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zoya Moslempour ◽  
Sepehr Sadighi ◽  
Ali Dashti ◽  
Ali Ahmadpour
Keyword(s):  
Molecular Sieves ◽  
Molecular Sieve ◽  
Coke Formation ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Na Ions ◽  
Temperature Programmed ◽  
And Performance ◽  
Physical And Chemical

Abstract To study the affinity of 3A aluminosilicate adsorbents to prevent oligomerization of olefin molecules and forming green oil, physical and chemical properties of 3A molecular sieves are measured by using characterization techniques such as temperature-programmed desorption (TPD), nitrogen (N2) and water adsorptions, X-ray diffraction (XRD), X-ray fluorescence (XRF), crushing strength, and carbon dioxide (CO2) adsorption. Moreover, coke formation affinities of the understudy adsorbents are evaluated in a bench-scale system using 1-butene and 1,3-butadiene at temperatures of 220 and 260 °C, and outcomes are validated against the actual data gathered from an industrial scale olefin dehydration plant. Results confirm that the type of binder and the amount of ion exchange affect the performance of a 3A molecular sieve nominated for dehydrating olefinic streams. The binder with the least amount of acidity is preferred, and at least 35% of Na ions of the 4A zeolite should be exchanged with K ions to make it applicable for synthesizing an appropriate 3A molecular sieve. Furthermore, to control the oligomerization and inhibit green oil formation, the CO2 adsorption and acidity of Trisiv shape molecular sieves with the sizes of 1/4 inch should be less than 0.5 wt % and 1.7 mmol NH3/g, respectively. For extrudate shape with the sizes of 1/16 inch CO2 adsorption and acidity should be less than 0.2 wt % and 2.2 mmol NH3/g, respectively.

The Different Morphology of Co3O4 Catalysts and Application in the Abatement of Carbon Monoxide

2021 ◽  
Vol 21 (12) ◽  
pp. 6082-6087
Author(s):  
Chih-Wei Tang ◽  
Hsiang-Yu Shih ◽  
Ruei-Ci Wu ◽  
Chih-Chia Wang ◽  
Chen-Bin Wang
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Co Oxidation ◽  
Nitrogen Adsorption ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Programmed ◽  
Adsorption Desorption

The increase of harmful carbon monoxide (CO) caused by incomplete combustion can affect human health even lead to suffocation. Therefore reducing the CO discharged by vehicles or factories is urgent to improve the air quality. The spinel cobalt (II, III) oxide (Co3O4) is an active catalyst for CO abatement. In this study, we tried to fabricate dispersing Co3O4 via the dispersion-precipitation method with acetic acid, formic acid, and oxalic acid as the chelating dispersants. Then, the asprepared samples were calcined at 300 ºC for 4 h to obtain active catalysts, and assigned as Co(A), Co(F) and Co(O) respectively, the amount of the dispersants used are labeled as I (0.12 mole), II (0.03 mole) and III (0.01 mole). For comparison, another CoAP sample was prepared via alkaliinduced precipitation and calcined at 300 ºC. All samples were characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), scanning electron microscope (SEM), and nitrogen adsorption/desorption system, and the catalytic activity focused on the CO oxidation. The influence of chelating dispersant on the performance of abatement of CO was pursued in this study. Apparently, the results showed that the chelating dispersant can influence the catalytic activity of CO abatement. An optimized ratio of dispersant can improve the performance, while excess dispersant lessens the surface area and catalytic performance. The series of Co(O) samples can easily donate the active oxygen since the labile Co–O bonding and indicated the preferential performance than both Co(A) and Co(F) samples. The nanorod Co(O)-II showed preferential for CO oxidation, T50 and T90 approached 96 and 127 ºC, respectively. Also, the favorable durability of Co(O)-II sample maintains 95% conversion still for 50 h at 130 ºC and does not emerge deactivation.

Preparation and Ultra-Deep Hydrorefining Performance of Ni-P/Al2O3-ZrO2 Catalysts

2011 ◽  
Vol 236-238 ◽  
pp. 724-727
Author(s):  
Feng Li ◽  
Hua Song ◽  
Hua Yang Zhang
Keyword(s):  
Chemical Precipitation ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Thiophene Hydrodesulfurization ◽  
Composite Oxides ◽  
Temperature Programmed ◽  
Supported Ni

A series of Al2O3-ZrO2 (AZ-X) composite oxides with different ZrO2 contents were prepared by a chemical precipitation method. Ni-P/AZ-X catalysts were prepared by temperature-programmed reduction. The supports and catalysts were extensively characterized by X-ray diffraction (XRD) and BET. The effects of support composition and P/Ni molar ratios on the catalytic performance of the catalysts were investigated by thiophene hydrodesulfurization (HDS) and pyridine hydrodenitrogenation (HDN). In comparison with Al2O3, Al2O3-ZrO2 (20 wt% ZrO2) composite oxide supported Ni-P catalyst exhibited higher activity and the activities of HDS and HDN increased by 7.5 % and 11.1 %, respectively. Studies of Ni-P/AZ-X catalysts with varying initial P/Ni molar ratios indicated that oxidic precursors with molar ratios of P/Ni = 2/1 yielded catalyst containing phase-pure Ni2P which exhibited optimal activity.

scholarly journals Effect of pore geometry of mesoporous supports on catalytic performances in methane reforming

2018 ◽  
Vol 171 ◽  
pp. 01003
Author(s):  
Joy Tannous ◽  
Leila Karam ◽  
Marie-Nour Kaydouh ◽  
Henri El Zakhem ◽  
Nissrine El Hassan ◽  
...  
Keyword(s):  
Coke Formation ◽  
Three Dimensional ◽  
Dry Reforming ◽  
Methane Reforming ◽  
X Ray Diffraction ◽  
Methane Dry Reforming ◽  
X Ray ◽  
Spent Catalysts ◽  
Temperature Programmed ◽  
Catalytic Performances

Catalysts prepared using three dimensional SBA-16 silica support (composed of micropores and cage-like mesopores) were tested in the reaction of methane dry reforming, in comparison with 2D hexagonal mesoporous SBA-15 support. The samples were evaluated by N2 sorption and X-Ray diffraction (XRD) for the assessment of their textural and structural properties. The reducibility was characterized by temperature programmed reduction (TPR). The catalytic performances were evaluated in methane dry reforming and spent catalysts (after reaction) were characterized for the evaluation of sintering and coke formation by TPH/MS, XRD and HR-TEM.

Effect of zinc introduction on catalytic performance of ZSM-5 in conversion of methanol to light olefins

2014 ◽  
Vol 68 (9) ◽  
Author(s):  
Su-Hong Zhang ◽  
Zhi-Xian Gao ◽  
Shao-Jun Qing ◽  
Sheng-Yu Liu ◽  
Yan Qiao
Keyword(s):  
Methanol Conversion ◽  
Catalytic Performance ◽  
Light Olefins ◽  
Acidic Property ◽  
X Ray Diffraction ◽  
Light Olefin ◽  
X Ray ◽  
Olefin Conversion ◽  
Methanol To Olefin ◽  
Temperature Programmed

AbstractThe effect of Zn on the catalytic performance of ZSM-5 in the methanol-to-olefin conversion was investigated. The samples were characterised by X-ray diffraction, N2 adsorption, FTIR, temperature-programmed desorption of ammonia and water, and Py-IR. The experimental results revealed Znmodified ZSM-5 to show a lower selectivity to light olefin at the higher reaction temperature of 520°C but a higher selectivity to light olefin at lower temperatures. As a comparison, the catalytic performance of Ca-modified ZSM-5 for the methanol conversion is also given. From the above results, it is concluded that Zn may play another role in the methanol conversion in addition to tuning the surface acidic property after modification.

scholarly journals Revisiting Oxidative Dehydrogenation of Ethane by W Doping into MoVMn Mixed Oxides at Low Temperature

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Mohammed H. Al-Hazmi ◽  
Taiwo Odedairo ◽  
Adel S. Al-Dossari ◽  
YongMan Choi
Keyword(s):  
Oxidative Dehydrogenation ◽  
Oxide Catalyst ◽  
Mixed Oxides ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxidative Dehydrogenation Of Ethane ◽  
Mixed Oxide Catalyst ◽  
Ethylene Selectivity ◽  
Temperature Programmed

The catalytic performance of MoVMnW mixed oxides was investigated in the oxidative dehydrogenation of ethane at three different reaction temperatures (235, 255, and 275°C) using oxygen as an oxidant. The catalysts were characterized by using X-ray diffraction, temperature-programmed reduction, and scanning electron microscopy. The MoVMnW mixed oxide catalyst showed the 70–90% of ethylene selectivity at the reaction temperatures. However, a significant decrease in the selectivity of ethylene was observed by increasing the reaction temperature from 235°C to 275°C.

scholarly journals Catalytic Dry Reforming and Cracking of Ethylene for Carbon Nanofilaments and Hydrogen Production Using a Catalyst Derived from a Mining Residue

Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1069 ◽  
Author(s):  
Abir Azara ◽  
El-Hadi Benyoussef ◽  
Faroudja Mohellebi ◽  
Mostafa Chamoumi ◽  
François Gitzhofer ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Fixed Bed ◽  
Dry Reforming ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Spent Catalysts ◽  
Temperature Programmed

In this study, iron-rich mining residue (UGSO) was used as a support to prepare a new Ni-based catalyst via a solid-state reaction protocol. Ni-UGSO with different Ni weight percentages wt.% (5, 10, and 13) were tested for C2H4 dry reforming (DR) and catalytic cracking (CC) after activation with H2. The reactions were conducted in a differential fixed-bed reactor at 550–750 °C and standard atmospheric pressure, using 0.5 g of catalyst. Pure gases were fed at a molar ratio of C2H4/CO2 = 3 for the DR reaction and C2H4/Ar = 3 for the CC reaction. The flow rate is defined by a GHSV = 4800 mLSTP/h.gcat. The catalyst performance is evaluated by calculating the C2H4 conversion as well as carbon and H2 yields. All fresh, activated, and spent catalysts, as well as deposited carbon, were characterized by Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), temperature programmed reduction (TPR), and thermogravimetric analysis (TGA). The results so far show that the highest carbon and H2 yields are obtained with Ni-UGSO 13% at 750 °C for the CC reaction and at 650 °C for the DR reaction. The deposited carbon was found to be filamentous and of various sizes (i.e., diameters and lengths). The analyses of the results show that iron is responsible for the growth of carbon nanofilaments (CNF) and nickel is responsible for the split of C–C bonds. In terms of conversion and yield efficiencies, the performance of the catalytic formulations tested is proven at least equivalent to other Ni-based catalyst performances described by the literature.

scholarly journals Purification of fuel ethanol engine exhaust with platinum-loaded Ce0.5Zr0.5O2 catalyst

2019 ◽  
Vol 9 ◽  
pp. 184798041988667
Author(s):  
Fei Zhao ◽  
Chunyu Wang ◽  
Xianjing Liu ◽  
Qingyue Luo ◽  
Ling Zhu
Keyword(s):  
Catalytic Performance ◽  
Fuel Ethanol ◽  
Photoelectron Spectra ◽  
Exhaust Gas ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Engine Exhaust ◽  
X Ray ◽  
Temperature Programmed ◽  
Three Way Catalyst

This work aimed at exploring a new kind of purification catalysts for fuel ethanol engine exhaust. Platinum loaded on Ce0.5Zr0.5O2 was prepared by impregnation method and characterized by X-ray diffraction, Brunner–Emmet–Teller measurements (BET), temperature-programmed reduction of hydrogen, scanning electron microscope, and X-ray photoelectron spectra. The three-way catalyst platinum/ceria–zirconia/fw is prepared with the paste ball mill coating technique. And the catalytic performance is evaluated under simulated fuel ethanol engine exhaust gas condition. The catalysts not only show excellent low-temperature performances and several-way catalytic activities for carbon monoxide, hydrocarbons, nitrogen oxides, and acetaldehyde but also have better high-temperature resistance. The addition of sulfur dioxide to feedstream degrades the performances of the catalysts.

Oxidation of thiophene over copper-manganese mixed oxides

2009 ◽  
Vol 63 (2) ◽  
Author(s):  
Małgorzata Szynkowska ◽  
Aneta Węglińska ◽  
Elżbieta Wojciechowska ◽  
Tadeusz Paryjczak
Keyword(s):  
Noble Metals ◽  
Mixed Oxides ◽  
Diffraction Method ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Copper Manganese ◽  
Different Temperatures ◽  
Temperature Programmed ◽  
Lower Temperature

AbstractCommercial hopcalite calcined at different temperatures and hopcalite modified with noble metals (Pt, Pd, and Au) were studied in oxidation of thiophene. Surface and bulk properties of catalysts were studied using temperature-programmed reduction (TPRH2), X-ray diffraction method (XRD) and thermal analysis (TG-DTA-MS). It was shown that calcined samples displayed higher activity in comparison with commercial untreated hopcalite; however, a lower temperature of calcination was favourable. High temperature of thermal treatment induced an increase in the crystallinity and a decrease in the surface area of the samples, and, as a consequence, the loss of catalysts activity. Moreover, marked improvement in the catalytic performance of platinum and palladium modified catalysts in relation to base hopcalite was observed. The obtained results indicate that the higher activity of samples containing Pt and Pd was accompanied by better reducibility of the catalysts.

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