scholarly journals Oxidative Dehydrogenation of n-Butane over LaV Catalysts Supported on TiO2

2013 ◽  
Vol 2013 ◽  
pp. 1-9
Author(s):  
Le Minh Cam ◽  
Ngo Duc Huyen ◽  
Nguyen Ngoc Ha
Keyword(s):  
Oxidative Dehydrogenation ◽  
Catalytic Performance ◽  
Slight Improvement ◽  
La Doping ◽  
Negative Effect ◽  
La Doped ◽  
Vanadia Catalysts

The catalytic performance of vanadia catalysts with 15 wt% V supported on TiO2and (15 wt% V + 4.6 wt% La) supported on TiO2in oxidative dehydrogenation (ODH) of n-butane was investigated. The catalysts were characterized by means of TPD-NH3, TPR-H2, UV-Vis, and BET. Testing of samples showed that vanadia catalysts were active for the reaction. It was found that La doping of V/TiO2catalyst had a negative effect on the dispersion of V species and led to formation of V2O5clusters. This resulted in a loss of activity. Although slight improvement of selectivity was observed in comparison to undoped V/TiO2samples due to lower acidity of La-doped –V/TiO2, this could not compensate the loss of activity and finally did not lead to higher butene yields.

Valence variation of phase-pure M1 MoVNbTe oxide by plasma treatment for improved catalytic performance in oxidative dehydrogenation of ethane

RSC Advances ◽  
2015 ◽  
Vol 5 (111) ◽  
pp. 91295-91301 ◽  
Author(s):  
Xin Chen ◽  
Qianli Yang ◽  
Bozhao Chu ◽  
Hang An ◽  
Yi Cheng
Keyword(s):  
Surface Modification ◽  
Metal Oxide ◽  
Plasma Treatment ◽  
Oxidative Dehydrogenation ◽  
Oxidation State ◽  
Active Sites ◽  
Oxygen Plasma ◽  
Catalyst Surface ◽  
Catalytic Performance ◽  
Phase Pure

This work presents a new method of catalyst surface modification by using oxygen plasma to change the oxidation state of active sites in metal oxide catalysts.

Effect of calcination temperature on the catalytic performance of Co9Fe3Bi1Mo12O51 in the oxidative dehydrogenation of n-butene to 1,3-butadiene

2008 ◽  
Vol 9 (10) ◽  
pp. 2059-2062 ◽  
Author(s):  
Ji Chul Jung ◽  
Howon Lee ◽  
Heesoo Kim ◽  
Sunyoung Park ◽  
Young-Min Chung ◽  
...  
Keyword(s):  
Calcination Temperature ◽  
Oxidative Dehydrogenation ◽  
Catalytic Performance

scholarly journals A Robust Two-Step Process for the Efficient Conversion of Acidic Soybean Oil for Biodiesel Production

Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 527 ◽  
Author(s):  
Gaojian Ma ◽  
Lingmei Dai ◽  
Dehua Liu ◽  
Wei Du
Keyword(s):  
Fatty Acid ◽  
Soybean Oil ◽  
Lower Cost ◽  
Immobilized Lipase ◽  
Acid Methyl Ester ◽  
Acid Value ◽  
Catalytic Performance ◽  
Raw Material ◽  
Biodiesel Production ◽  
Negative Effect

Acidic oil, which is easily obtained and with lower cost, is a potential raw material for biodiesel production. Apart from containing large quantity of FFAs (free fatty acids), acidic oil usually contains some amount of inorganic acid, glycerides and some other complex components, leading to complicated effect on lipase’s catalytic performance. Exploring the efficient process of converting acidic oil for biodiesel production is of great significance to promote the use of acidic oil. A two-step conversion process for acidic soybean oil was proposed in this paper, where sulfuric acid-mediated hydrolysis was adopted first, then the hydrolyzed free fatty acid, collected from the upper oil layer was further subject to the second-step esterification catalyzed by immobilized lipase Novozym435. Through this novel process, the negative effect caused by harmful impurities and by-product glycerol on lipase was eliminated. A fatty acid methyl ester (FAME) yield of 95% could be obtained with the acid value decreased to 4 mgKOH/g from 188 mgKOH/g. There was no obvious loss in lipase’s activity and a FAME yield of 90% could be maintained with the lipase being repeatedly used for 10 batches. This process was found to have a good applicability to different acidic oils, indicating it has great prospect for converting low quality oil sources for biodiesel preparation.

Effect of Bi on catalytic performance and stability of MoVTeNbO catalysts in oxidative dehydrogenation of ethane

2017 ◽  
Vol 534 ◽  
pp. 58-69 ◽  
Author(s):  
E.V. Ishchenko ◽  
R.V. Gulyaev ◽  
T.Yu. Kardash ◽  
A.V. Ishchenko ◽  
E.Yu. Gerasimov ◽  
...  
Keyword(s):  
Oxidative Dehydrogenation ◽  
Catalytic Performance ◽  
Oxidative Dehydrogenation Of Ethane

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

Catalysts ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 829 ◽  
Author(s):  
Zhang ◽  
Yuan ◽  
Miao ◽  
Li ◽  
Shan ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Catalytic Performance ◽  
High Yield ◽  
Side Chain ◽  
Impregnation Method ◽  
Basic Sites ◽  
Lewis Acidic Sites ◽  
X Zeolite ◽  
Acidic Sites ◽  
Negative Effect

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.

scholarly journals Influence of incorporating a small amount of silica on the catalytic performance of a MoO3/Al2O3 catalyst in ethanol oxidative dehydrogenation

2018 ◽  
Vol 16 (6) ◽  
Author(s):  
Aline Villarreal ◽  
Gabriella Garbarino ◽  
Paola Riani ◽  
Aida Gutiérrez Alejandre ◽  
Jorge Ramírez ◽  
...  
Keyword(s):  
Oxidative Dehydrogenation ◽  
Active Sites ◽  
Catalytic Performance ◽  
Redox Behavior ◽  
Acid Base ◽  
Pure Alumina ◽  
Molybdenum Catalyst ◽  
Al2o3 Catalyst ◽  
Dehydrogenation Of Ethanol

The influence of incorporating a small amount of silica on the catalytic performance of MoO3/Al2O3 catalyst was studied. Molybdenum supported on pure alumina and 5% SiO2-Al2O3 supports were synthesized. The catalysts were characterized by XRD, Raman, UV-Vis and IR spectroscopies, FE-SEM microscopy, and their activity was evaluated in the oxidative dehydrogenation of ethanol to acetaldehyde. Molybdenum supported on pure alumina gives a 74% yield to acetaldehyde (at 573 K) due to the generation of oxy-dehydrogenation active sites by molybdenum and to the decrement of the alumina dehydration sites. For the molybdenum catalyst supported on silica-containing alumina, the molybdenum species were displaced from the strongest alumina’s acid-base couples, located on nanoparticles edges, corners and defects, to weaker ones located on plane faces causing the rise of weakly bonded species with less active redox behavior.  

Catalytic performance of sucrose-derived CMK-3 in oxidative dehydrogenation of propane to propene

2012 ◽  
Vol 445-446 ◽  
pp. 321-328 ◽  
Author(s):  
Piotr Michorczyk ◽  
Piotr Kuśtrowski ◽  
Paula Niebrzydowska ◽  
Anna Wach
Keyword(s):  
Oxidative Dehydrogenation ◽  
Catalytic Performance ◽  
Oxidative Dehydrogenation Of Propane
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