Search

Your search keyword '"Hwang, Young Kyu"' showing total 637 results
Start Over Author "Hwang, Young Kyu"
637 results on '"Hwang, Young Kyu"'

15. Continuous production of 1,2-pentanediol from furfuryl alcohol over highly stable bimetallic Ni–Sn alloy catalysts.

Author

Nimbalkar, Ajaysing S., Oh, Kyung-Ryul, Hong, Do-Young, Park, Byung Gyu, Lee, Maeum, Hwang, Dong Won, Awad, Ali, Upare, Pravin P., Han, Seung Ju, and Hwang, Young Kyu

Abstract

The development of robust long-lasting catalysts with enduring activity is essential for the sustainable conversion of biomass into value-added compounds. This study demonstrates the continuous conversion of furfuryl alcohol (FAL) into 1,2-pentanediol (1,2-PDO) using economical bimetallic Ni–Sn/ZnO catalysts. Various Ni/Sn ratios were used to characterize the catalytic surface and ascertain the active sites, revealing a vital collaborative impact between Ni–Sn alloy phases and adjacent SnOx species. This synergy significantly enhances the targeted breaking of the δ-C5–O1 bond in FAL and THFA, leading to continuous and selective 1,2-PDO production. The alteration in the binding energies of Ni and Sn validates the modification in the coordination environment of Ni caused by the transfer of electrons from highly valent Sn. Density functional theory studies combined with experimental results demonstrated that the Ni3Sn2 (101) plane promoted the selective synthesis of 1,2-PDO via the THFA dehydrogenation–scission mechanism. Furthermore, the Ni3Sn2 phase exhibits superior capability in adsorbing and dissociating H2 compared with Ni3Sn and metallic Ni. The representative 3Ni–3Sn/ZnO catalyst demonstrated high efficiency in the continuous conversion of FAL into 1,2-PDO with 91% yield, and a decline in conversion and selectivity was observed after 300 h because of the accumulation of carbonaceous species on the catalytic surface. Notably, a straightforward regeneration process restored the original catalytic activity, enabling the continuous production of 1,2-PDO for a total of ∼450 h, yielding 438 g (4464 mmol) of 1,2-PDO. This advanced catalytic system demonstrates effective scalability in biomass conversion, facilitating environmentally friendly scale-up operation. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

21. Front Cover: Nickel‐Tin Nanoalloy Supported ZnO Catalysts from Mixed‐Metal Zeolitic Imidazolate Frameworks for Selective Conversion of Glycerol to 1,2‐Propanediol (ChemSusChem 3/2024)

Author

Nimbalkar, Ajaysing S., primary, Oh, Kyung‐Ryul, additional, Han, Seung Ju, additional, Yun, Gwang‐Nam, additional, Cha, Seung Hyeok, additional, Upare, Pravin P., additional, Awad, Ali, additional, Hwang, Dong Won, additional, and Hwang, Young Kyu, additional

Published
2024
Full Text
View/download PDF

32. Nickel‐Tin Nanoalloy Supported ZnO Catalysts from Mixed‐Metal Zeolitic Imidazolate Frameworks for Selective Conversion of Glycerol to 1,2‐Propanediol.

Author

Nimbalkar, Ajaysing S., Oh, Kyung‐Ryul, Han, Seung Ju, Yun, Gwang‐Nam, Cha, Seung Hyeok, Upare, Pravin P., Awad, Ali, Hwang, Dong Won, and Hwang, Young Kyu

Subjects
CATALYST supports, GLYCERIN, CATALYST selectivity, BIOMASS chemicals, LEWIS acidity, ACTIVATION energy
Abstract

The successful synthesis of finely tuned Ni1.5Sn nanoalloy phases containing ZnO catalyst with a small particle size (6.7 nm) from a mixed‐metal zeolitic imidazolate framework (MM‐ZIF) is investigated. The catalyst was evaluated for the efficient production of 1,2‐propanediol (1,2‐PDO) from crude glycerol and comprehensively characterized using several analytical techniques. Among the catalysts, 3Ni1Sn/ZnO (Ni/Sn=3/1) showed the best catalytic performance and produced the highest yield (94.2 %) of 1,2‐PDO at ~100 % conversion of glycerol; it also showed low apparent activation energy (15.4 kJ/mol) and excellent stability. The results demonstrated that the synergy between Ni−Sn alloy, finely dispersed Ni metallic sites, and the Lewis acidity of SnOx species‐loaded ZnO played a pivotal role in the high activity and selectivity of the catalyst. The confirmation of acetol intermediate and theoretical calculations verify the Ni1.5Sn phases provide the least energetic pathway for the formation of 1,2‐PDO selectively. The reusability of solvent for successive ZIF synthesis, along with the excellent recyclability of the ZIF‐derived catalyst, enables an overall sustainable process. We believe that the present synthetic protocol that uses MM‐ZIF for the conversion of various biomass‐derived platform chemicals into valuable products can be applied to various nanoalloy preparations. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

34. Room temperature reduction of nitrogen oxide on iron Metal-Organic Frameworks

Author

Daturi, Marco, primary, BLASIN-AUBE, Vanessa, additional, Yoon, Ji Wong, additional, Bazin, Philippe, additional, Vimont, Alexandre, additional, Chang, Jong-San, additional, Hwang, Young Kyu, additional, Seo, You-Kyong, additional, Jang, Seunghun, additional, Chang, Hyunju, additional, Wuttke, Stefan, additional, Horcajada, Patricia, additional, Haneda, Masaaki, additional, and Serre, Christian, additional

Published
2023
Full Text
View/download PDF

46. Single-Atom Iridium-Catalyst-Embedded Zeolitic Imidazolate Frameworks for CO2 and Glycerol Transformations

Author

Oh, Kyung-Ryul, primary, Yun, Gwang-Nam, additional, Kim, Ki-Duk, additional, Cheong, Yeon-Joo, additional, Yoo, Changho, additional, Prihatno, Fajar, additional, Jang, Hye-Young, additional, Valekar, Anil H., additional, Cha, Ga-Young, additional, Lee, Mijung, additional, Jung, Jaehoon, additional, Kwon, Young-Uk, additional, and Hwang, Young Kyu, additional

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results