scholarly journals Catalytic Oxidation of Chlorobenzene over Pd-TiO2 /Pd-Ce/TiO2 Catalysts

Catalysts ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 347 ◽  
Author(s):  
Wenjun Liang ◽  
Xiaoyan Du ◽  
Yuxue Zhu ◽  
Sida Ren ◽  
Jian Li
Keyword(s):  
Catalytic Activity ◽  
Catalytic Oxidation ◽  
Calcination Temperature ◽  
Catalyst Activity ◽  
Space Velocity ◽  
Impregnation Method ◽  
Tio2 Catalyst ◽  
Metal Support ◽  
Oxidation Efficiency

A series of Pd-TiO2/Pd-Ce/TiO2 catalysts were prepared by an equal volume impregnation method. The effects of different Pd loadings on the catalytic activity of chlorobenzene (CB) were investigated, and the results showed that the activity of the 0.2%-0.3% Pd/TiO2 catalyst was optimal. The effect of Ce doping enhanced the catalytic activity of the 0.2% Pd-0.5% Ce/TiO2 catalyst. The characterization of the catalysts using BET, TEM, H2-TPR, and O2-TPD showed that the oxidation capacity was enhanced, and the catalytic oxidation efficiency was improved due to the addition of Ce. Ion chromatography and Gas Chromatography-Mass Spectrometer results showed that small amounts of dichlorobenzene (DCB) and trichlorobenzene (TCB) were formed during the decomposition of CB. The results also indicated that the calcination temperature greatly influenced the catalyst activity and a calcination temperature of 550 °C was the best. The concentration of CB affected its decomposition, but gas hourly space velocity had little effect. H2-TPR indicated strong metal–support interactions and increased dispersion of PdO in the presence of Ce. HRTEM data showed PdO with a characteristic spacing of 0.26 nm in both 0.2% Pd /TiO2 and 0.2% Pd-0.5% Ce/TiO2 catalysts. The average sizes of PdO nanoparticles in the 0.2% Pd/TiO2 and 0.2% Pd-0.5% Ce/TiO2 samples were 5.8 and 4.7 nm, respectively. The PdO particles were also deposited on the support and they were separated from each other in both catalysts.

scholarly journals Influences of Different Preparation Conditions on Catalytic Activity of Ag2O-Co3O4/γ-Al2O3for Hydrogenation of Coal Pyrolysis

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Lei Zhang ◽  
Sha Xiang-ling ◽  
Lei Zhang ◽  
Wang Rui ◽  
Zhang Lixin ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Catalyst Activity ◽  
Preparation Condition ◽  
Impregnation Method ◽  
Coal Pyrolysis ◽  
Calcination Time ◽  
Calcination Temperatures ◽  
Preparation Conditions ◽  
Cobalt Loading

A series of catalysts of Ag2O-Co3O4/γ-Al2O3was prepared by equivalent volume impregnation method. The effects of the metal loading, calcination time, and calcination temperatures of Ag and Co, respectively, on the catalytic activity were investigated. The optimum preparing condition of Ag2O-Co3O4/γ-Al2O3was decided, and then the influence of different preparation conditions on catalytic activity of Ag2O-Co3O4/γ-Al2O3was analyzed. The results showed the following: (1) at the same preparation condition, when silver loading was 8%, the Ag2O-Co3O4/γ-Al2O3showed higher catalyst activity, (2) the catalyst activity had obviously improved when the cobalt loading was 8%, while it was weaker at loadings 5% and 10%, (3) the catalyst activity was influenced by different calcination temperatures of silver, but the influences were not marked, (4) the catalyst activity can be influenced by calcination time of silver, (5) different calcination times of cobalt can also influence the catalyst activity of Ag2O-Co3O4/γ-Al2O3, and (6) the best preparation conditions of the Ag2O-Co3O4/γ-Al2O3were silver loading of 8%, calcination temperature of silver of 450°C, and calcinations time of silver of 4 h, while at the same time the cobalt loading was 8%, the calcination temperature of cobalt was 450°C, and calcination time of cobalt was 4 h.

Effect of calcination temperature on properties of waste alkaline battery-based catalysts for deep oxidation of toluene and o-xylene

2020 ◽  
pp. 0958305X2093255
Author(s):  
Young-Kwon Park ◽  
Min Ki Kim ◽  
Sang Chul Jung ◽  
Wang Geun Shim ◽  
Seong Ho Jang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Thermo Gravimetric Analysis ◽  
Space Velocity ◽  
Deep Oxidation ◽  
Bet Surface Area ◽  
Gravimetric Analysis ◽  
Average Pore ◽  
X Ray ◽  
Alkaline Battery

To evaluate waste alkaline battery (WB) as a catalyst for deep oxidation of toluene and o-xylene, we investigated how calcination temperature influenced the catalytic activity of WB-based catalyst for catalyst preparation. Physicochemical properties of WB-based catalysts were characterized by BET (Brunauer Emmett Teller) analysis, XRD (X-ray diffraction), SEM/EDX (scanning electron microscope/energy dispersive X-ray), TGA/DTA (thermo gravimetric analysis/differential thermal analysis), and H2-TPR (hydrogen temperature programmed reduction). Major elements of WB-based catalysts were carbon, manganese, zinc, and iron. The catalytic activity of WB-based catalyst was significantly influenced by calcination temperatures ranging from 300 °C–600°C. An increase calcination temperature resulted in a significant decrease in the BET surface area and concentrations of surface carbon and chlorine of the WB-based catalyst, while levels of other components increased. The average pore diameter of the WB-based catalyst calcined at 400 °C (WB (400) catalyst) was the smallest. The concentrations of manganese and iron in WB (400) catalyst were the highest, while those of manganese and iron in the WB-based catalyst calcined at 300 °C (WB (300) catalyst) were the lowest. Therefore, a good performance of WB (400) catalyst was likely due to its higher concentrations of manganese and iron and smaller pore size. When GHSV (gas hourly space velocity) was 40,000 h−1, toluene and o-xylene were completely oxidized on WB (400) catalyst at 430 °C and 440 °C, respectively.

Research on the Catalytic Activity of MnyCezOx/TiO2 for Ethyl Acetate Oxidation

2013 ◽  
Vol 781-784 ◽  
pp. 308-311 ◽  
Author(s):  
Xin Li ◽  
Wei Su ◽  
Qi Bin Xia ◽  
Zhi Meng Liu
Keyword(s):  
Catalytic Activity ◽  
Ethyl Acetate ◽  
High Activity ◽  
Fixed Bed ◽  
Space Velocity ◽  
Fixed Bed Reactor ◽  
Impregnation Method ◽  
Acetate Oxidation ◽  
Acetate Concentration ◽  
Molar Ratios

Manganese and cerium based catalysts with different Mn/Ce molar ratios prepared by impregnation method for ethyl acetate oxidation. The activity tests of the samples were performed in a fixed-bed reactor. The effect of gas hourly space velocity (GHSV) and ethyl acetate concentration on the catalytic activity of the catalyst were also investigated. The results showed that these catalysts had high activity for the catalytic oxidation of ethyl acetate, of which the catalyst Mn0.9Ce0.1Ox/TiO2exhibitedthe bestactivity, and the temperature required for 90% conversion of ethyl acetate was at 216 °C. The catalyst Mn0.9Ce0.1Ox/TiO2still maintained high activity in the range of GHSV (16,500 to 48,500 h-1) and ethyl acetate concentration (4526 to 7092 mg/m3). In additional, experiments for measuring stability of Mn0.9Ce0.1Ox/TiO2were carried out, and experimental results showed that the good stability of Mn0.9Ce0.1Ox/TiO2was kept after it has run for 25 hours.

Effect of Nanosized Gold Particle Addition to Supported Metal Oxide Catalyst in Methanol Oxidation

2006 ◽  
Vol 6 (11) ◽  
pp. 3589-3593
Author(s):  
Ki-Joong Kim ◽  
Young-Jae You ◽  
Min-Chul Chung ◽  
Chan-Soon Kang ◽  
Kyong-Hwan Chung ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Metal Oxide ◽  
Methanol Oxidation ◽  
Catalyst Activity ◽  
Chemical Species ◽  
Impregnation Method ◽  
Gold Particles ◽  
Transmission Electron ◽  
Supported Metal Oxide ◽  
Supported Metal

Gold has rarely been utilized as a catalytic component because of its poor affinity to chemical species. It is however known that nanosized gold particles promote the dissociation of oxygen or hydrogen. In this study, alumina-supported metal oxide catalysts were prepared by impregnation method and applied to methanol oxidation. The dispersion form and size of the gold particles were observed by transmission electron microscopy (TEM). In the results, the maximum catalytic activity was obtained over the ZnO/Al2O3 catalyst, and the optimum loading was 4 wt%. Furthermore, nanosized gold particles at various loadings were added to ZnO/Al2O3 catalyst by deposition method. The gold particles on Au/ZnO/Al2O3 catalyst were well dispersed and the catalyst activity was remarkably increased compared to ZnO/Al2O3 catalyst. The role of gold particles in the increased catalytic activity is discussed and a possible mechanism is presented.

Effect of the Calcination Temperature on Ni2P/TiO2-Al2O3 Catalyst Structure and Catalytic Activity for Hydrodesulfurization

2014 ◽  
Vol 1025-1026 ◽  
pp. 419-422
Author(s):  
Feng Li ◽  
Zai Shun Jin ◽  
Hua Lin Song ◽  
Yong Sheng Li ◽  
Jian Zhong Xu
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Reaction Temperature ◽  
Space Velocity ◽  
Nickel Phosphide ◽  
Catalyst Structure ◽  
Weight Hourly Space Velocity

Nickel phosphide Ni2P catalysts supported on TiO2-Al2O3support were prepared by co-impregnation. The catalysts were characterized by XRD, BET, and XPS. The effects of calcination temperature on catalyst structure and HDS activity were studied. The results indicated that the catalyst prepared with calcination temperature of 773 K exhibited the best performance. At a reaction temperature of 606 K, a pressure of 3.0 MPa, a hydrogen/oil ratio of 500 (V/V), and a weight hourly space velocity (WHSV) of 2.0 h-1, the conversion of DBT HDS was 96.0%.

scholarly journals Synergistic Effects of Co3O4-CeO2 Nanoparticles towards Catalytic Oxidation of Aromatic Hydrocarbons: A Study in Association with Carbon Monoxide and Humidity

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Trung Dang-Bao ◽  
Hong Phuong Phan ◽  
Phung Anh Nguyen ◽  
Pham Phuong Trang Vo ◽  
Van Tien Huynh ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Catalytic Oxidation ◽  
Synergistic Effects ◽  
Active Oxygen Species ◽  
High Dispersion ◽  
High Catalytic Activity ◽  
Impregnation Method ◽  
Temperature Programmed ◽  
The Stability

In this study, a series of Co3O4-CeO2 nanocomposites with various Co3O4 loading were fabricated by the impregnation method using cobalt(II) acetate as the cobalt precursor for the treatment of benzene, toluene, ethylbenzene, and xylene (BTEX). The as-prepared Co3O4-CeO2 nanocomposites were thoroughly characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brumauer-Emmett-Teller (BET), hydrogen temperature-programmed reduction (H2-TPR), and temperature-programmed desorption (O2-TPD). The excellent reproduction of active oxygen species caused by the high dispersion of Co3O4 crystals on the CeO2 supports was established. In addition, the reduction peaks of Co3O4-CeO2 nanocomposites were found at much lower temperatures compared to pure CeO2, considering their unique redox property influencing on the high catalytic activity. Among the characterized materials, the 5.0 wt.% Co3O4 supported on CeO2 (5.0Co–Ce) was the best system for catalytic oxidation of xylene, along with excellent performances in the cases of benzene, ethylbenzene, and toluene. Its catalytic activity increased in the order: benzene < xylene < ethylbenzene < toluene . Furthermore, the addition of carbon monoxide (CO) as a coreactant permitted to improve the catalytic performances in such oxidations as well as the stability of as-prepared catalysts, even under humid conditions.

scholarly journals Study of the Metal–Support Interaction and Electronic Effect Induced by Calcination Temperature Regulation and Their Effect on the Catalytic Performance of Glycerol Steam Reforming for Hydrogen Production

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3149
Author(s):  
Songshan Zhu ◽  
Yunzhu Wang ◽  
Jichang Lu ◽  
Huihui Lu ◽  
Sufang He ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Calcination Temperature ◽  
Steam Reforming ◽  
Electronic Effect ◽  
Catalytic Performance ◽  
Tio2 Catalyst ◽  
Support Interaction ◽  
Metal Support Interaction ◽  
Metal Support ◽  
Ni Species

Steam reforming of glycerol to produce hydrogen is considered to be the very promising strategy to generate clean and renewable energy. The incipient-wetness impregnation method was used to load Ni on the reducible carrier TiO2 (P25). In the process of catalyst preparation, the interaction and electronic effect between metal Ni and support TiO2 were adjusted by changing the calcination temperature, and then the activity and hydrogen production of glycerol steam reforming reaction (GSR) was explored. A series of modern characterizations including XRD, UV-vis DRS, BET, XPS, NH3-TPD, H2-TPR, TG, and Raman have been applied to systematically characterize the catalysts. The characterization results showed that the calcination temperature can contribute to varying degrees of influences on the acidity and basicity of the Ni/TiO2 catalyst, the specific surface area, together with the interaction force between Ni and the support. When the Ni/TiO2 catalyst was calcined at 600 °C, the Ni species can be produced in the form of granular NiTiO3 spinel. Consequently, due to the moderate metal–support interaction and electronic activity formed between the Ni species and the reducible support TiO2 in the NiO/Ti-600C catalyst, the granular NiTiO3 spinel can be reduced to a smaller Ni0 at a lower temperature, and thus to exhibit the best catalytic performance.

The Effects of Different Preparation Conditions of IR Catalyst on the Simultaneous Removal of Soot and NOx in the Presence of Rich Oxygen and H2O as Well as SO2

2012 ◽  
Vol 428 ◽  
pp. 61-64 ◽  
Author(s):  
Ting Kun Gu ◽  
Rong Shu Zhu ◽  
Feng Ouyang
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Supported Catalysts ◽  
Catalytic Performance ◽  
Simultaneous Removal ◽  
Impregnation Method ◽  
Support Material ◽  
Calcination Time ◽  
Preparation Conditions ◽  
Calcination Atmosphere

A series of Ir-supported catalysts were prepared by incipient impregnation method. The activity of Ir catalyst for the simultaneous removal of soot and NOx in the presence of rich-oxygen and H2O as well as SO2 has been studied, and the effects of calcination temperature, calcination time, calcination atmosphere, loading, carrier and precursor on its catalytic performance has also been investigated. Ir catalyst exhibits a high activity. With the calcination temperature increasing, Ir catalytic activity increases firstly and then decreases, and the optimal calcination temperature is 900°C. With the calcination time prolonged, Ir catalytic activity also increases firstly and then decreases, and the optimal calcination time is 3h. The optimal calcination atmosphere is 1.5vol.% H2/N2. Support material and precursor have a little effect on the catalytic activity, and the order is Ir/TiO2 > Ir/ZrO2 > Ir/SiO2 > Ir/Al2O3 > Ir/ZSM-5 and IrCl (CO)[P(C6H5)3]2/ZrO2 > H2IrCl6·6H2O/ZrO2 > IrCl4·4H2O/ZrO2.

Enhanced Activity of Fe-Doped Cu/H-Sep for the SCR of NO with Propylene in the Presence of Oxygen

2014 ◽  
Vol 700 ◽  
pp. 261-264
Author(s):  
Yang Li ◽  
Qing Ye ◽  
Zhi Hao Zhang ◽  
Yun Fang Qi ◽  
Li Sha Liu
Keyword(s):  
Catalytic Activity ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Copper Species ◽  
Catalytic Activities ◽  
Support Interaction ◽  
Scr Of No ◽  
Metal Support Interaction ◽  
Metal Support ◽  
Incipient Wetness

Cu/H-Sep and Cu-Fe/H-Sep samples were prepared by the incipient wetness impregnation method. These catalysts were characterized by means of XRF, XRD, BET, XPS, and H2-TPR techniques, and their catalytic activities were performed by the SCR of NO with propylene. The results show that the Cu-Fe/H-Sep catalyst exhibited the best performance in the C3H6-SCR of NO. After investigation by H2-TPR, XRD and XPS, the result showed that the higher reducibility, more amount of isolated Cu2+, higher dispersion of copper species, and stronger metal-support interaction were responsible for the excellent catalytic activity of Cu-Fe/H-Sep.

Preparation of Nano Ni2P/TiO2-Al2O3 Catalyst and Catalytic Activity for Hydrodesulfurization

2014 ◽  
Vol 983 ◽  
pp. 71-74
Author(s):  
Hua Song ◽  
Zi Dong Wang ◽  
Zai Shun Jin ◽  
Feng Li ◽  
Huai Yuan Wang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Reaction Temperature ◽  
Space Velocity ◽  
Impregnation Method ◽  
Catalyst Structure ◽  
Weight Hourly Space Velocity

nanonickel phosphide Ni2P catalysts supported on TiO2-Al2O3 support were prepared by impregnation. The catalysts were characterized by XRD, BET, and XPS. The effects of impregnation method,Ni2P loading on catalyst structure and HDS activity were studied. The results indicated that co-impregnation method is beneficial to the formation of Ni2P and can avoid the formation of Ni12P5. The catalyst prepared with co-impregnation method, Ni2P loading of 30% exhibited the best performance. At a reaction temperature of 606 K, a pressure of 3.0 MPa, a hydrogen/oil ratio of 500 (V/V), and a weight hourly space velocity (WHSV) of 2.0 h-1, the conversion of DBT HDS was 96.0%.

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