Effect of Fe Additives on the Catalytic Performance of Ion-Exchanged CsX Zeolites for Side-Chain Alkylation of Toluene with Methanol

The side-chain alkylation of toluene with methanol was investigated over some Fe-modified Cs ion-exchanged X zeolite (CsX) catalysts prepared via the impregnation method using different iron sources. The absorption/activation behaviors of the reactants on the surface of the catalysts were studied by in situ Fourier-transform infrared (FT-IR) spectroscopy and temperature programmed desorption (TPD) mass measurements. Modification of CsX with a small amount of FeCl3 could result in a considerable decrease in catalytic activity, due mainly to the remarkable decrease in the density of acidic and basic sites of the catalysts. Interestingly, the Fe(NO3)3-modified CsX with an optimum Fe loading of 0.15 wt.% shows improved catalytic activity and high yield compared to the side-chain alkylation products. Modification of CsX with Fe(NO3)3 could also result in a decrease in basic sites of the catalyst. However, such a change does not bring an obvious negative effect on the adsorption/activation of toluene, while it could effectively inhibit the generation of the undesired bidentate formate. Furthermore, the introduced FeOx species (derived from the decomposition of Fe(NO3)3) may also act as new Lewis acidic sites to participate in the activation of methanol and to stabilize the formed active intermediates (i.e., unidentate formate). Therefore, modification of CsX with a suitable amount of Fe(NO3)3 may adjust its adsorption/activation ability for reagents by changing the acid–base properties of the catalyst, which can finally enhance the catalytic performance for the side-chain alkylation of toluene with methanol.

Download Full-text

An efficient Fe2O3/HY catalyst for Friedel–Crafts acylation of m-xylene with benzoyl chloride

RSC Advances ◽

10.1039/c4ra04984e ◽

2014 ◽

Vol 4 (70) ◽

pp. 36951-36958 ◽

Cited By ~ 16

Author(s):

Manman Mu ◽

Ligong Chen ◽

Yunlong Liu ◽

Wangwang Fang ◽

Yang Li

Keyword(s):

Catalytic Activity ◽

Iron Oxide ◽

Benzoyl Chloride ◽

Catalytic Performance ◽

Reaction Parameters ◽

Hy Zeolite ◽

Lewis Acidic Sites ◽

Acidic Sites ◽

Excellent Catalytic Performance

Iron oxide supported on HY zeolite was prepared and exhibited excellent catalytic performance in the acylation of m-xylene with benzoyl chloride. It was characterized by XRD, BET, XPS, NH3-TPD and Py-IR. The catalytic activity of Fe2O3/HY is enhanced with the increase of Lewis acidic sites. Furthermore, the reaction parameters were optimized. Finally, the catalyst was easily separated reused for five runs without appreciable loss of catalytic activity.

Download Full-text

Research of Catalytic Performance over Transition Metal Modified MnOx-CeOx/ACF Catalysts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.1945 ◽

2011 ◽

Vol 383-390 ◽

pp. 1945-1950 ◽

Cited By ~ 1

Author(s):

Bo Xiong Shen ◽

Ting Liu ◽

Ning Zhao ◽

Juan Ma ◽

Xiao Cui Hao

Keyword(s):

Catalytic Activity ◽

Thermal Treatment ◽

Transition Metal ◽

Catalytic Reduction ◽

Surface Acidity ◽

Catalytic Performance ◽

Impregnation Method ◽

Active Components ◽

Scr Of No ◽

Negative Effect

The catalyst of MnOx-CeOx/ACF prepared by impregnation method was used for low-temperature selective catalytic reduction (SCR) of NO with NH3, and more than 90% NO conversion was obtained at 230°C. Fe、Cu or V was used respectively to prepare transition metal modified MnOx-CeOx/ ACF catalysts which had lower catalytic activity than that over MnOx-CeOx/ACF. SEM, N2 adsorption and NH3-TPD were used to analyze the catalysts. The results showed that transition metal modified catalysts had a reduced surface area, pore volume and surface acidity. SO2 had a negative effect on SCR performance of the catalysts. Fe modified catalyst exhibited SO2 tolerance in the first 6h in the presence of 100ppm SO2. Thermal treatment in N2 at 350°C was used to regenerate the deactivated catalysts by SO2. The decomposition of ammonium salts recovered the catalytic activity to some extent. The sulfated active components in deactivated catalysts after the thermal treatment enhanced the surface acidity of the catalysts.

Download Full-text

Performance Analysis of TiO2-Modified Co/MgAl2O4 Catalyst for Dry Reforming of Methane in a Fixed Bed Reactor for Syngas (H2, CO) Production

Energies ◽

10.3390/en14113347 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3347

Author(s):

Arslan Mazhar ◽

Asif Hussain Khoja ◽

Abul Kalam Azad ◽

Faisal Mushtaq ◽

Salman Raza Naqvi ◽

...

Keyword(s):

Catalytic Activity ◽

Fixed Bed ◽

Catalytic Performance ◽

Dry Reforming ◽

Fixed Bed Reactor ◽

Dry Reforming Of Methane ◽

Catalyst Stability ◽

Feed Ratio ◽

Catalyst Loading ◽

Impregnation Method

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process.

Download Full-text

Construction of Solely Lewis acidic sites on Zr-MCM-41 and the catalytic activity for the Prins condensation of β-pinene and paraformaldehyde to nopol

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2016.05.010 ◽

2016 ◽

Vol 230 ◽

pp. 166-176 ◽

Cited By ~ 10

Author(s):

Xing Chu ◽

Dan Zhou ◽

Dan Li ◽

Kun Xia ◽

Ning Gan ◽

...

Keyword(s):

Catalytic Activity ◽

Lewis Acidic Sites ◽

Acidic Sites ◽

Mcm 41

Download Full-text

Preparation of Ni/ZrO2/SiO2 Catalyst and its Application in Hydrogenation of CO2 to Methane

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1001.79 ◽

2020 ◽

Vol 1001 ◽

pp. 79-83

Author(s):

Zhen Xing Han ◽

Si Xi Guo ◽

Kai Ming Li ◽

Bing Yao ◽

Ming Song ◽

...

Keyword(s):

Catalytic Activity ◽

Low Temperature ◽

Catalytic Performance ◽

Experimental Results ◽

Impregnation Method ◽

Energy And Environment ◽

Supported Ni ◽

Hydrogenation Of Co

The hydrogenation of CO2 to CH4 can realize the utilization of CO2, which has an important implications to both the energy and environment. As a result of the low catalytic activity of the supported Ni/SiO2 catalyst, the ZrO2 is added to improve its catalytic performance by the impregnation method. The experimental results show that ZrO2 is an effective promoter to enhance the low-temperature catalytic activity of Ni/SiO2 catalyst.

Download Full-text

Low Temperature NH3-SCR over Mn-Ce Oxides Supported on MCM-41 from Diatomite

Materials ◽

10.3390/ma12223654 ◽

2019 ◽

Vol 12 (22) ◽

pp. 3654 ◽

Cited By ~ 3

Author(s):

Mingxuan Ma ◽

Xiaoyu Ma ◽

Suping Cui ◽

Tingting Liu ◽

Yingliang Tian ◽

...

Keyword(s):

Molecular Sieves ◽

Synthesis Method ◽

Molar Ratio ◽

Impregnation Method ◽

Catalyst Carrier ◽

Nh3 Scr ◽

Catalytic Material ◽

Lewis Acidic Sites ◽

Acidic Sites ◽

Mcm 41

A series of MCM-41 molecular sieves with different molar ratio of template to silicon were synthesized through hydrothermal synthesis method by using cetyltrimethylammonium bromide (CTAB) as the template, diatomite as the silicon source. By using impregnation method, the Mn-Ce/MCM-41 SCR molecular sieve-based catalysts were prepared. The results observed that when the molar ratio of template to silicon was 0.2:1, the MCM-41 as catalyst carrier has the highest surface area and largest pore volume, it also presented typically ordered hexagonal arrays of uniform channels. The denitration catalytic material based on this carrier has a high number of Lewis acidic sites, and the denitration efficiency can reach more than 93%.

Download Full-text

Catalytic Properties of Ni/CNTs and Ca-Promoted Ni/CNTs for Methanation Reaction of Carbon Dioxide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.924.217 ◽

2014 ◽

Vol 924 ◽

pp. 217-226 ◽

Cited By ~ 5

Author(s):

Xiang Feng Hu ◽

Wen Yang ◽

Ning Wang ◽

Shi Zhong Luo ◽

Wei Chu

Keyword(s):

Carbon Dioxide ◽

Carbon Nanotubes ◽

Catalytic Activity ◽

Catalytic Properties ◽

Supported Catalyst ◽

Catalytic Performance ◽

Impregnation Method ◽

Methanation Reaction ◽

Ni Species ◽

Nickel Species

Nickel/carbon nanotubes (Ni/CNTs), Nickel/alumina (Ni/Al2O3), calcium-promoted Ni/CNTs and calcium-promoted Ni/Al2O3 were synthesized by impregnation method. Methanation of carbon dioxide was used as a probe to evaluate their catalytic performance. The features of these Ni-based catalysts were investigated via XRD, H2-TPR, H2-TPD and the N2 adsorptiondesorption isotherms. H2-TPR showed that nickel species on Ni/CNTs was reduced more easily with respect to that on Ni/Al2O3, and addition of Ca can increase the content of easily reducible Ni species for Ni/CNTs. XRD and H2-TPD indicated that addition of Ca promoted dispersion for CNTs-supported catalyst. These finding ultimately enhanced catalytic activity and stability for Ni/CNTs catalyst modified with Ca.

Download Full-text

The Roles of the Structure and Basic Sites of Sodium Titanates on Transesterification Reactions to Obtain Biodiesel

Catalysts ◽

10.3390/catal9120989 ◽

2019 ◽

Vol 9 (12) ◽

pp. 989

Author(s):

Josue J. Machorro ◽

Ana L. Lazaro ◽

Fabricio Espejel-Ayala ◽

Eduardo Coutiño-Gonzalez ◽

Juan C. Chavarria-Hernandez ◽

...

Keyword(s):

Catalytic Activity ◽

Heterogeneous Catalysts ◽

Catalytic Performance ◽

Influential Factor ◽

Biodiesel Production ◽

Materials Characterization ◽

Basic Sites ◽

Calcination Temperatures ◽

Input Variables ◽

Associated Species

Sodium titanates were evaluated as heterogeneous catalysts for biodiesel production. Materials were prepared using an experimental design considering NaOH and TiO2 concentrations and hydrothermal and calcination temperatures as input variables. Materials characterization was carried out by DRX-Rietveld refinement, CO2-TPD, and XPS. Statistical analysis of the experimental results indicates that the calcination temperature is the most influential factor in the formation of sodium titanates with high catalytic performance in transesterification reactions. Further analysis of the oil-to-biodiesel conversion revealed that the catalytic activity of sodium titanates is directly correlated to the catalyst associated species and to the density of medium-strong basic sites on the surface of the material, obtaining up to 95% conversion to biodiesel at 60 °C using 3.6% weight catalyst with respect to oil.

Download Full-text

Properties and catalytic performance of sulphate-vanadia impregnated fumed silica as oxidative catalyst

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v11n2.372 ◽

2015 ◽

Vol 11 (2) ◽

Author(s):

Nor Masdiana Zulkeple ◽

Norhasyimah Mohd Kamal ◽

Jamilah Mohd Ekhsan ◽

Salasiah Che Me ◽

Swee Ean Lim ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Catalytic Activity ◽

Charge Transfer ◽

Surface Area ◽

Sulphuric Acid ◽

Fumed Silica ◽

Catalytic Performance ◽

Support Surface ◽

High Catalytic Activity ◽

Impregnation Method

A series of sulphate-vanadia impregnated fumed silica oxidative catalysts were synthesized via impregnation method. The samples were prepared by impregnation of 1 wt% of vanadium and 0.2 M of sulphuric acid onto fumed silica as support. Surface area of the silica supported samples were similar of 118 m2/g. UV-Vis DRS results showed existence of o supported V species and the charge transfer bands associated with O2- to V5+ in tetrahedral environments. Catalytic performance were evaluated via epoxidation of 1-octene to 1,2-epoxyoctane using hydrogen peroxide as an oxidant. It had been demonstrated that sulphate-vanadia impregnated fumed silica had high catalytic activity of 626 ± 0.2 mmol epoxide was produced after 24 h reaction. This may indicate that more oxidative sites were generated after the impregnation of V and sulphate onto the SiO2 matrixes.

Download Full-text