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

To mitigate global problems related to energy and global warming, it is helpful to develop an ammonia synthesis process using catalysts that are highly active under mild conditions. Here we show that the ammonia synthesis activity of Ru/Ba/LaCeOx pre-reduced at 700 °C is the highest reported among oxide-supported Ru catalysts. Our results indicate that low crystalline oxygen-deficient composite oxides, which include Ba2+, Ce3+ and La3+, with strong electron-donating ability, accumulate on Ru particles and thus promote N≡N bond cleavage, which is the rate determining step for ammonia synthesis.

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Electron Donation by Low-Crystalline Ba-La-Ce Oxygen-Deficient Composite Oxide Accumulating on Ru Nanoparticles for Ammonia Synthesis under Mild Conditions

10.26434/chemrxiv.7763657 ◽

2019 ◽

Author(s):

Katsutoshi Sato ◽

Shin-ichiro Miyahara ◽

Yuta Ogura ◽

Kotoko Tsujimaru ◽

Yuichiro Wada ◽

...

Keyword(s):

Ammonia Synthesis ◽

Bond Cleavage ◽

Synthesis Process ◽

Strong Electron ◽

Mild Conditions ◽

Ru Nanoparticles ◽

Rate Determining Step ◽

Highly Active ◽

Composite Oxides ◽

Low Crystalline

To mitigate global problems related to energy and global warming, it is helpful to develop an ammonia synthesis process using catalysts that are highly active under mild conditions. Here we show that the ammonia synthesis activity of Ru/Ba/LaCeOx pre-reduced at 700 °C is the highest reported among oxide-supported Ru catalysts. Our results indicate that low crystalline oxygen-deficient composite oxides, which include Ba2+, Ce3+ and La3+, with strong electron-donating ability, accumulate on Ru particles and thus promote N≡N bond cleavage, which is the rate determining step for ammonia synthesis.

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Ru Nanoparticles Immobilized on Chitosan as Effective Catalysts for Boosting NH3BH3 Hydrolysis

ChemCatChem ◽

10.1002/cctc.202100781 ◽

2021 ◽

Author(s):

Jiaxin Liu ◽

Peiyun Li ◽

Renfeng Jiang ◽

Xiu-Cheng Zheng ◽

Pu Liu ◽

...

Keyword(s):

Ru Nanoparticles

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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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Ru nanoparticles loaded on tannin immobilized collagen fibers for catalytic hydrolysis of ammonia borane

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2020.12.152 ◽

2021 ◽

Author(s):

Ling Fu ◽

Li Cai

Keyword(s):

Ammonia Borane ◽

Collagen Fibers ◽

Catalytic Hydrolysis ◽

Ru Nanoparticles ◽

Hydrolysis Of

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CuAl2O4–CuO–Al2O3 catalysts prepared by flame-spray pyrolysis for glycerol hydrogenolysis

Molecular Catalysis ◽

10.1016/j.mcat.2021.111426 ◽

2021 ◽

pp. 111426

Author(s):

Naphaphan Kunthakudee ◽

Pongtanawat Khemthong ◽

Chuleeporn Luadthong ◽

Joongjai Panpranot ◽

Okorn Mekasuwandumrong ◽

...

Keyword(s):

Spray Pyrolysis ◽

Flame Spray Pyrolysis ◽

Flame Spray ◽

Glycerol Hydrogenolysis

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Oxygen-deficient TiO2 and carbon coupling synergistically boost the activity of Ru nanoparticles for the alkaline hydrogen evolution reaction

Journal of Materials Chemistry A ◽

10.1039/d0ta11986e ◽

2021 ◽

Vol 9 (16) ◽

pp. 10160-10168

Author(s):

Zhongzhe Wei ◽

Zijiang Zhao ◽

Jing Wang ◽

Qiang Zhou ◽

Chenxia Zhao ◽

...

Keyword(s):

Band Gap ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

One Pot ◽

Carbon Nanocomposites ◽

Ru Nanoparticles

Ru nanoparticles/oxygen-deficient TiO2@carbon nanocomposites are efficiently fabricated via one-pot pyrolysis. TiO2-VO and carbon narrow the band gap, optimize ΔGH2O and ΔGH* and synergistically boost the activity of Ru for the alkaline HER.

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