Influence of Catalyst Reduction Temperature on Autogenous Glycerol Hydrogenolysis over NiAl Catalyst

It is usually necessary to first perform temperature reduction treatment to enable the catalyst to exert its catalytic activity in the subsequent process of preparing carbon nanotubes by chemical vapor deposition. In this experiment, Fe-Mo/Al2O3 catalyst was prepared based on microreactor, and the effect of reduction temperature on the microstructure of the catalyst and the morphology of carbon nanotubes was investigated. The results show that the reduction temperature has a significant effect on the microstructure of the catalyst, which in turn affects its catalytic activity and the yield and quality of carbon nanotubes. Moderately reducing the reduction temperature during the catalyst reduction process is beneficial to increase the catalytic activity of the catalyst. However, although its sintering degree could be weakened when the catalyst was reduced at an excessively low temperature of 350 °C, its catalytic efficiency was greatly reduced and the degree of defects of the catalyzed carbon nanotubes was increased. When the catalysts calcined at 450 °C and reduced at 600 °C, the catalysts show excellent catalytic activity, and catalytic efficiency can reach 74.76%. In addition, the reduction temperature also has a certain effect on carbon nanotubes. As the reduction temperature increases, the span of carbon nanotubes is relatively concentrated, but the specific gravity of the thicker outer diameter gradually increases. As for the defect degree of carbon nanotubes, the carbon nanotubes M600-600 is better and the defects are fewer when the reduction temperature is reduced from 670 °C to 600 °C.

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Reaction Pathway Study of Catalyst Ni, W, Cu/ Kieselguhr Catalyst: Effects of Catalyst Reduction Temperature, Reduction Time and Amount of Catalyst Used

Indian Journal of Science and Technology ◽

10.17485/ijst/2017/v10i31/113916 ◽

2017 ◽

Vol 10 (31) ◽

pp. 1-6

Author(s):

Sanghmitra Saxena ◽

Renu Sharma ◽

Tanuja Srivastava ◽

◽

...

Keyword(s):

Reaction Pathway ◽

Reduction Temperature ◽

Reduction Time ◽

Temperature Reduction ◽

Catalyst Reduction

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Effect of syngas conversion and catalyst reduction temperature in the synthesis of ethanol: concentration of water vapor in mesoporous Rh/MCM-41 catalyst

Catalysis Communications ◽

10.1016/j.catcom.2015.06.015 ◽

2015 ◽

Vol 69 ◽

pp. 183-187 ◽

Cited By ~ 6

Author(s):

Luis Lopez ◽

Jorge Velasco ◽

Saul Cabrera ◽

Magali Boutonnet ◽

Sven Järås

Keyword(s):

Water Vapor ◽

Ethanol Concentration ◽

Reduction Temperature ◽

Syngas Conversion ◽

Catalyst Reduction ◽

Mcm 41

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Effects of Reduction Temperature on Selective Hydrogenation of Crotonalde-hyde over Ir/ZrO2 Catalyst

CHINESE JOURNAL OF CATALYSIS (CHINESE VERSION) ◽

10.3724/sp.j.1088.2012.10919 ◽

2013 ◽

Vol 33 (2) ◽

pp. 348-353

Author(s):

Lin ZHU ◽

Jiqing LU ◽

Guanqun XIE ◽

Ping CHEN ◽

Mengfei LUO

Keyword(s):

Selective Hydrogenation ◽

Reduction Temperature

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Effects of impregnation solvent and reduction temperature on the catalytic performance of Pd/Al2O3 in the selective hydrogenation of 1,3-butadiene

Reaction Kinetics Mechanisms and Catalysis ◽

10.1007/s11144-011-0318-z ◽

2011 ◽

Vol 103 (2) ◽

pp. 405-417 ◽

Cited By ~ 6

Author(s):

Kanda Pattamakomsan ◽

Francisco Jose Cadete Santos Aires ◽

Kongkiate Suriye ◽

Joongjai Panpranot

Keyword(s):

Selective Hydrogenation ◽

Catalytic Performance ◽

Reduction Temperature

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Controlling the selectivity of supported Ru nanoparticles during glycerol hydrogenolysis: C‐O vs C‐C cleavage

ChemCatChem ◽

10.1002/cctc.202001881 ◽

2020 ◽

Author(s):

Meenakshisundaram Sankar ◽

Susana Guadix-Montero ◽

Alba Santos Hernandez ◽

Nian Lei ◽

David J. Morgan ◽

...

Keyword(s):

Ru Nanoparticles ◽

Glycerol Hydrogenolysis

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Experimental and computational study on roles of WOx promoting strong metal support promoter interaction in Pt catalysts during glycerol hydrogenolysis

Scientific Reports ◽

10.1038/s41598-020-79764-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tinnakorn Saelee ◽

Poonnapa Limsoonthakul ◽

Phakaorn Aphichoksiri ◽

Meena Rittiruam ◽

Mongkol Lerdpongsiripaisarn ◽

...

Keyword(s):

Density Of States ◽

Design Guidelines ◽

Total Density ◽

High Electron ◽

Metal Support Interaction ◽

Metal Support ◽

Glycerol Hydrogenolysis ◽

The Stability ◽

Total Density Of States ◽

Promoter Interaction

AbstractBiodiesel is of high interest due to increased demand for energy with the concern regarding more sustainable production processes. However, an inevitable by-product is glycerol. Hence, the conversion of this by-product to higher-value chemicals, especially 1,3-propanediol (1,3-PDO) via glycerol hydrogenolysis reaction, is one of the most effective pathways towards a profitable process. In general, this process is catalyzed by a highly active Pt-based catalyst supported on γ-Al2O3. However, its low 1,3-PDO selectivity and stability due to surface deactivation of such catalysts remained. This led to the surface modification by WOx to improve both the selectivity by means of the increased Brønsted acidity and the stability in terms of Pt leaching-resistance. Hence, we applied experimental and density functional theory (DFT)-based techniques to study the fundamentals of how WOx modified the catalytic performance in the Pt/γ-Al2O3 catalyst and provided design guidelines. The effects of WOx promoter on improved activity were due to the shifting of the total density of states towards the antibonding region evident by the total density of states (TDOS) profile. On the improved 1,3-PDO selectivity, the main reason was the increasing number of Brønsted acid sites due to the added WOx promoter. Interestingly, the stability improvement was due to the strong metal-support interaction (SMSI) that occurred in the catalyst, like typical high leaching-resistant catalysts. Also, the observed strong metal-support-promoter interaction (SMSPI) is an additional effect preventing leaching. The SMSPI stemmed from additional bonding between the WOx species and the Pt active site, which significantly strengthened Pt adsorption to support and a high electron transfer from both Pt and Al2O3 to WOx promoter. This suggested that the promising promoter for our reaction performed in the liquid phase would improve the stability if SMSI occurred, where the special case of the WOx promoter would even highly improve the stability through SMSPI. Nevertheless, various promoters that can promote SMSPI need investigations.

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Glycerol Hydrogenolysis with In Situ Hydrogen Produced via Methanol Steam Reforming: The Promoting Effect of Pd on a Cu/ZnO/Al2O3 Catalyst

Catalysts ◽

10.3390/catal11010110 ◽

2021 ◽

Vol 11 (1) ◽

pp. 110

Author(s):

Yuanqing Liu ◽

Chau T. Q. Mai ◽

Flora T. T. Ng

Keyword(s):

Steam Reforming ◽

Catalyst Activity ◽

Promoting Effect ◽

Glycerol Conversion ◽

Glycerol Hydrogenolysis ◽

Glycerol Dehydration ◽

Effect Of Pd ◽

Al2o3 Catalyst ◽

Reaction Equilibrium

The glycerol hydrogenolysis to produce 1,2-propanediol without using externally supplied hydrogen was investigated using methanol present in crude glycerol to provide in situ hydrogen via its steam reforming reaction. This paper focuses on the promoting effect of Pd on the reactivity of a Cu/Zn/Al2O3 catalyst. Adding 2 wt% Pd onto a Cu/ZnO/Al2O3 catalyst significantly improved the selectivity to 1,2-propanediol from 63.0% to 82.4% and the glycerol conversion from 70.2% to 99.4%. This enhancement on the catalytic activity by Pd is mainly due to the improved hydrogenation of acetol, which is the intermediate formed during the glycerol dehydration. The rapid hydrogenation of acetol can shift the reaction equilibrium of glycerol dehydration forward resulting in a higher glycerol conversion. The improved reducibility of the catalyst by Pd allows the catalyst to be reduced in situ during the reaction preventing any loss of catalyst activity due to any potential oxidation of the catalyst. The catalyst was slightly deactivated when it was firstly recycled resulting in a 5.4% loss of glycerol conversion due to the aggregation of Cu and the deactivation became less noticeable upon further recycling.

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