Operando DRIFTS-MS Study of WGS and rWGS Reaction on Biochar-Based Pt Catalysts: The Promotional Effect of Na

Biochar-based Pt catalysts, unpromoted and Na-promoted, were prepared by an incipient wetness impregnation method and characterised by Inductively coupled plasma mass spoectrometry (ICP-MS) analysis, X-ray diffraction, N2 adsorption and transmission, and scanning electron microscopy. It was demonstrated that a sodium promoter modifies the acid-base properties of the support, altering the Pt-support interaction. An operando Diffuse reflectance infrared fourier transform spectroscopy-mass spectrometry (DRIFTS-MS) study was performed to gain insights into the reaction pathways and the mechanism of the Water-Gass-Shift (WGS) and the Reverse Water-Gass-Shift (rWGS) reactions. It was demonstrated that the addition of Na enhances the catalytic performance due to the changes induced by the alkali in the electronic structure of the Pt active sites. This effect favours the activation of H2O molecules during the WGS reaction and the dissociation of CO2 during the rWGS reaction, although it may also favour the consecutive CO methanation pathway.

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Activity of yFe-10Cu/H-Sep and xCu/H-Sep for the Selective Catalytic Reduction of NO with Propylene

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.281 ◽

2012 ◽

Vol 518-523 ◽

pp. 281-284

Author(s):

Qing Ye ◽

Hai Ping Wang ◽

Hai Xia Zhao ◽

Shui Yuan Cheng ◽

Tian Fang Kang

Keyword(s):

Catalytic Reduction ◽

Catalytic Performance ◽

High Dispersion ◽

High Catalytic Activity ◽

Incipient Wetness Impregnation ◽

Impregnation Method ◽

Promotional Effect ◽

Scr Of No ◽

Metal Support Interaction ◽

Metal Support

Cu supported on acid-treated sepiolite catalysts (xCu/H-Sep, x = 0  20.0 wt%) or Cu-Fe mixed supported on acid-treated sepiolite catalysts (yFe-10Cu/H-Sep, y = 0  20.0 wt%) were prepared by the incipient wetness impregnation method. The xCu/H-Sep and yFe-10Cu/H-Sep catalysts were characterized by means of XRD, BET, XRF, XPS, and H2-TPR techniques, and their catalytic activities were evaluated for the SCR of NO with propylene. XPS and XRD results indicate that there was the co-presence of Cu+-Cu2+ and Fe2+-Fe3+ over the surfaces of yFe-10Cu/H-Sep catalysts, and there was a strong interaction between Cu, Fe and sepiolite. High promotional effect of iron additive on the catalytic performance of Cu/H-Sep catalyst were found in C3H6-SCR of NO reaction. The highest activity of 65% NO conversion was obtained over 15Fe-10Cu/H-Sep catalyst at 280 oC under the condition of 1000 ppm NO, 1000 ppm C3H6, and 5% O2. The high catalytic activity of 15Fe-10Cu/H-Sep catalyst for NO reduction was due to its high reducibility to activate C3H6 to selectively reduce NO in the presence of excess O2. The high dispersion of copper oxides and strong metal-support interaction over 15Fe-10Cu/H-Sep catalyst also improve its catalytic performance.

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Formaldehyde Total Oxidation on Manganese-Doped Hydroxyapatite: The Effect of Mn Content

Catalysts ◽

10.3390/catal10121422 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1422

Author(s):

Dayan Chlala ◽

Jean-Marc Giraudon ◽

Madona Labaki ◽

Jean-François Lamonier

Keyword(s):

Fourier Transform ◽

Inductively Coupled Plasma ◽

Effect Study ◽

Gravimetric Analysis ◽

Impregnation Method ◽

Total Oxidation ◽

Oh Groups ◽

Inductively Coupled ◽

Diffuse Reflectance Infrared ◽

Manganese Species

An aqueous impregnation method using manganese (II) nitrate precursor, followed by calcination at 400 °C, was carried out for the preparation of manganese doped hydroxyapatite catalysts (MnxHap; x = Mn wt.%: 2.5, 5.0, 10, 20, and 30 based on MnO2). Methods of characterization including inductively coupled plasma spectroscopy (ICP), N2 physisorption, X-ray Diffraction (XRD), Fourier-Transform Transmission Infrared (FT-IR), Raman, and Thermal gravimetric analysis (TGA/MS) analysis were used for the identification of Mn species and its surrounding environment. Raman spectroscopy indicated the presence of the ε-MnO2 phase for Mn20Hap and Mn30Hap in agreement with the XRD results and the presence of β-MnOOH species for Mn5Hap and Mn10Hap. The formaldehyde total oxidation was investigated on these catalysts and it was shown that Mn5Hap was the most active catalyst, achieving a normalized rate of formaldehyde (HCHO) conversion into CO2 per mole of Mn of 0.042 h−1 at a temperature of 145 °C. The well dispersed oxidized manganese species on Hap with a medium Mn AOS (average oxidation state) were mainly responsible for this performance. Since HCHO was retained on the surface of all catalysts during the catalytic test, the combined Diffuse Reflectance Infrared Fourier Transform spectroscopy (DRIFT) experiment at room temperature and thermodesorption (TD)-FTIR identified formate species as their oxidation consumed surface OH groups. A stability test and moisture effect study showed that the presence of water vapor has a beneficial effect on the performances of the catalyst.

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Evaluation of La-Doped CaO Derived from Cockle Shells for Photodegradation of POME

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.14.1.3318.205-218 ◽

2019 ◽

Vol 14 (1) ◽

pp. 205 ◽

Cited By ~ 4

Author(s):

Siti Shariah Ghazali ◽

Kem Ley Kem ◽

Rohayu Jusoh ◽

Sureena Abdullah ◽

Jun Haslinda Shariffuddin

Keyword(s):

Calcium Oxide ◽

Inductively Coupled Plasma ◽

Active Sites ◽

Cost Effective ◽

Bet Surface Area ◽

Impregnation Method ◽

Wastewater Remediation ◽

X Ray ◽

Inductively Coupled ◽

La Doped

Photocatalysis has merged to be one of the most promising technology in wastewater remediation. However, the application of photocatalysis in treating palm oil mill effluent (POME) is still limited. Many researches were conducted to explore simple and cost-effective alternatives to replace TiO2 for various industrial purposes. Therefore, the aim of this study is to synthesize and characterize lanthanum doped calcium oxide (La/CaO) as photocatalyst as well as to evaluate the performance of these photocatalysts in the degradation of POME. The photocatalyst used in this study was converted from cockle shells to transform into calcium oxide (CaO) through calcination process. The CaO produced was doped with 1 wt%, 3 wt%, and 5 wt% of lanthanum (La) using wet impregnation method to enhance its photocatalytic activity. The photocatalysts were characterised using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Energy-Dispersion X-ray (EDX) and Inductively Coupled Plasma Mass Spectrometry (ICPMS). Then, this photocatalyst was performed on POME under UVC in a batch system by using different La/CaO at optimum catalyst dosage of 3.0 g/L. Through this research, it was found that the POME degradation through photocatalytic reaction was increased with the incorporation of La where 3 wt% La/CaO shows the highest POME degradation compared to others. This is due to the larger BET surface area that provides more active sites resulted from the incorporation of La. The findings of this study imply that the contaminants in POME can be reduced by utilizing CaO derived from cockle shells. Copyright © 2019 BCREC Group. All rights reservedReceived: 1st October 2018; Revised: 12nd January 2019; Accepted: 17th January 2019; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Ghazali, S.S., Kem, W.L., Jusoh, R., Abdullah, S., Shariffuddin, J.H. (2019). Evaluation of La-Doped CaO Derived from Cockle Shells for Photodegradation of POME. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 205-218 (doi:10.9767/bcrec.14.1.3318.205-218)Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.3318.205-218

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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

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666200825144543 ◽

2020 ◽

Vol 23 ◽

Cited By ~ 1

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.

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On efficiency of vanadium-oxide promoter in cobalt Fischer – Tropsch catalysts

Kataliz v promyshlennosti ◽

10.18412/1816-0387-2021-1-2-15 ◽

2021 ◽

Vol 1 (1-2) ◽

pp. 15

Author(s):

Elham Yaghoobpour ◽

Yahya Zamani ◽

Saeed Zarrinpashne ◽

Akbar Zamaniyan

Keyword(s):

Vanadium Oxide ◽

Active Sites ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Bet Surface Area ◽

Incipient Wetness Impregnation ◽

Impregnation Method ◽

Fischer Tropsch ◽

Co Conversion ◽

Loading Amount

Promoters and their loading amount have crucial roles in cobalt Fischer – Tropsch catalysts. In this regard, the effects of vanadium oxide (V2O5) as a proposed promoter for Co catalyst supported on TiO2 have been investigated. Three catalysts with 0, 1, and 3 wt.% of V2O5 promoter loading are prepared by the incipient wetness impregnation method, and characterized by the BET surface area analyzer, XRD, H2-TPR, and TEM techniques. The fixed-bed reactor was employed for their evaluations. It was found that the catalyst containing 1 wt.% V2O5 has the best performance among the evaluated catalysts, demonstrating remarkable selectivity: 92 % C5+ and 5.7 % CH4, together with preserving the amount of CO conversion compared to the unpromoted catalyst. Furthermore, it is reported that the excess addition of V2O5 promoter (> 1 wt.%) in the introduced catalyst leads to the detrimental effect on the CO conversion and C5+ selectivity, mainly owing to diminished active sites by V2O5 loading.

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

Crystals ◽

10.3390/cryst10060530 ◽

2020 ◽

Vol 10 (6) ◽

pp. 530 ◽

Cited By ~ 2

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.

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

Progress in Reaction Kinetics and Mechanism ◽

10.1177/1468678319887931 ◽

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.

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Fe-Containing MOFs as Seeds for the Preparation of Highly Active Fe/Al-SBA-15 Catalysts in the NAlkylation of Aniline

Molecules ◽

10.3390/molecules24152695 ◽

2019 ◽

Vol 24 (15) ◽

pp. 2695 ◽

Cited By ~ 1

Author(s):

Mhadmhan ◽

Marquez-Medina ◽

Romero ◽

Reubroycharoen ◽

Luque

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Catalytic Performance ◽

Alkylation Reaction ◽

X Ray Diffraction ◽

X Ray ◽

Inductively Coupled ◽

Highly Active ◽

Milling Method ◽

Plasma Mass Spectrometry

We have successfully incorporated iron species into mesoporous aluminosilicates (AlSBA15) using a simple mechanochemical milling method. The catalysts were characterized by nitrogen physisorption, inductively coupled plasma mass spectrometry (ICP-MS), pyridine (PY) and 2,6-dimethylpyridine (DMPY) pulse chromatography titration, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). The catalysts were tested in the N-alkylation reaction of aniline with benzyl alcohol for imine production. According to the results, the iron sources, acidity of catalyst and reaction conditions were important factors influencing the reaction. The catalyst showed excellent catalytic performance, achieving 97% of aniline conversion and 96% of imine selectivity under optimized conditions.

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Fabrication of the Hierarchical HZSM-5 Membrane with Tunable Mesoporosity for Catalytic Cracking of n-Dodecane

Catalysts ◽

10.3390/catal9020155 ◽

2019 ◽

Vol 9 (2) ◽

pp. 155 ◽

Cited By ~ 8

Author(s):

Zhenheng Diao ◽

Lushi Cheng ◽

Xu Hou ◽

Di Rong ◽

Yanli Lu ◽

...

Keyword(s):

Catalytic Cracking ◽

Inductively Coupled Plasma ◽

Catalytic Performance ◽

X Ray Diffraction ◽

Inductively Coupled ◽

Swelling Agent ◽

Ft Ir ◽

Temperature Programmed ◽

Adsorption Desorption

Hierarchical HZSM-5 membranes were prepared on the inner wall of stainless steel tubes, using amphiphilic organosilane (TPOAC) and mesitylene (TMB) as a meso-porogen and a swelling agent, respectively. The mesoporosity of the HZSM-5 membranes were tailored via formulating the TPOAC/Tetraethylorthosilicate (TPOAC/TEOS) ratio and TMB/TPOAC ratio, in synthesis gel, and the prepared membranes were systematically characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), N2 adsorption–desorption, N2 permeation, inductively coupled plasma (ICP), in situ fourier transform infrared (FT-IR), ammonia temperature-programmed desorption (NH3-TPD), etc. It was found that the increase of the TPOAC/TEOS ratio promoted a specific surface area and diffusivity of the HZSM-5 membranes, as well as decreased acidity; the increase of the TMB/TPOAC ratios led to an enlargement of the mesopore size and diffusivity of the membranes, but with constant acid properties. The catalytic performance of the prepared HZSM-5 membranes was tested using the catalytic cracking of supercritical n-dodecane (500 °C, 4 MPa) as a model reaction. The hierarchical membrane with the TPOAC/TEOS ratio of 0.1 and TMB/TPOAC ratio of 2, exhibited superior catalytic performances with the highest activity of up to 13% improvement and the lowest deactivation rate (nearly a half), compared with the microporous HZSM-5 membrane, due to the benefits of suitable acidity, together with enhanced diffusivity of n-dodecane and cracking products.

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Effect of Preparation Mode on the Properties of Mn-Na-W/SiO2 Catalysts for Oxidative Coupling of Methane: Conventional Methods vs. POSS Nanotechnology

Eurasian Chemico-Technological Journal ◽

10.18321/ectj430 ◽

2016 ◽

Vol 18 (2) ◽

pp. 93 ◽

Cited By ~ 10

Author(s):

I.Z. Ismagilov ◽

E.V. Matus ◽

V.V. Kuznetsov ◽

M.A. Kerzhentsev ◽

S.A. Yashnik ◽

...

Keyword(s):

Catalytic Performance ◽

Oxidative Coupling Of Methane ◽

Molar Ratio ◽

High Dispersion ◽

Incipient Wetness Impregnation ◽

Impregnation Method ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Preparation Mode ◽

Slurry Method ◽

Conventional Methods

Reflectance spectroscopic methods the electronic, redox and structural properties of Mn-Na-W/SiO2 catalysts prepared by the incipient wetness impregnation method and mixture slurry method were studied in detail. Since POSS nanotechnology (POSS = polyhedral oligomeric silsesquioxanes) has attracted attention as tooling for synthesis of catalysts with novel properties and functionalities, we expanded this method for the preparation of Mn-Na-W/SiO2 catalyst. The physicochemical and catalytic properties of Mn-Na-W/SiO2 catalysts prepared by conventional methods and POSS nanotechnology were examined comparatively. In all studied Mn-Na-W/SiO2 catalysts both individual oxides (MnOx, WO3) and bimetal oxide phases (Na2WO4, MnWO4) are found in addition to oxide particles of high dispersion. The UV-Vis Diffuse Reflectance indicates that Na+ cations facilitates stabilization of octahedrally coordinated Mn3+Oh cations in the isolated state, while Mn3+Oh promote the disordering of W6+ cations in the supported system. The Mn-Na-W/SiO2 prepared using metal-POSS precursors marks out presence of unglobular SiO2 particles, higher dispersion of MnOx and MnWO4 particles and more easily reducible metal-oxide species. The catalysts prepared by incipient impregnation method and mixture slurry method have practically similar catalytic performance while the catalyst prepared by POSS nanotechnology method shows lower activity and selectivity. At 800‒850 °C the increase of C2 hydrocarbons yield from 4 to 15% and the rise of molar ratio С2Н4/C2H6 from 0.2 to 1 are observed when impregnation or mixture slurry method are used for catalyst preparation instead of POSS nanotechnology method.

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