(382bg) Versatile Ga-Zeolites for Industrial Applications: From Biomass Upgrading to Hydrocarbon Dehydrogenation

The production of para-xylene (p-xylene) from renewable resources is a promising route to sustainable aromatic chemicals. One such pathway involves the cycloaddition of biomass-derived dimethylfuran (DMF) with ethylene, and subsequent dehydration of the formed Diels–Alder adduct to p-xylene. we demonstrate that Ga,Al-*BEA zeolites are effective bifunctional catalysts for p-xylene production from bio-derived 2,5-dimethylfuran (DMF) through tandem Diels–Alder/dehydration reactions. A series of catalysts was synthesized via direct (one-pot) and post-synthesis techniques to introduce Brønsted and Lewis acid sites. Our findings reveal that Ga,Al-*BEA catalysts enhance DMF conversion and p-xylene selectivity in comparison to Al-*BEA zeolite. The pairing of Ga and Al in a single catalyst yields fewer byproducts, such as 2,5-hexanedione, alkylated products, and oligomers. Comparisons of zeolites prepared with different Ga content reveal a higher turnover frequency for DMF conversion to p-xylene over Ga,Al-*BEA catalysts prepared by a one-pot synthesis compared to Al-*BEA catalysts. We observed a correlation between Ga content and p-xylene selectivity and yield, which is attributed to the Brønsted acidity of Ga framework sites (with reduced acid strength compared to Al sites) and to the Lewis acidity of extra-framework Ga species.

Alongside the series of Ga,Al-*BEA zeolite, we developed a pure gallosilicate zeolite Beta via one-pot synthesis without the use of an inorganic structure directing agent (ISDA). These catalysts were applied to another biomass upgrading reaction, the deoxygenation of glycerol, to enhance the yield of acetol (hydroxyacetone). Through systematic screening of reaction conditions to control product distribution across various zeolite catalysts, including Ga,Al-*BEA, Ga-*BEA, Ga-MFI, we observed higher selectivity toward acetol against acrolein.

In a separate study, we developed a novel in situ method to generate extra-framework gallium nitride (GaN) within the micropores of Ga-chabazite (Ga-CHA) zeolites through high-temperature treatment with ammonia (NH₃). This process simultaneously induces demetallation of framework Ga and nitridation, resulting in a GaN formation within the cha cages, eliminating the need for post-synthesis impregnation. Characterization via color change, powder X-ray diffraction (PXRD), and X-ray photoelectron spectroscopy (XPS) confirms the formation and increasing concentration of GaN with higher Ga content. In ethane dehydrogenation (EDH) testing, these in situ-generated [GaN]-Ga-CHA catalysts exhibit enhanced activity compared to the parent H-Ga-CHA, demonstrating the catalytic potential of confined GaN species. Collectively, this study is a proof of principle for the method of scavenging metals in zeolites frameworks to generate multifunctional catalysts in situ, thereby circumventing the difficulties associated with encapsulating large active sites in small pores of zeolite catalysts.

Together, these studies highlight the versatility of Ga-zeolites as multifunctional catalysts for both renewable chemical production and light alkane conversion, offering scalable solutions for industrial catalytic processes. [1-3]

[1] Jaeyul Kim, Sunkyu Kim, Seungwan Seo, Raul F. Lobo, Jeffrey D. Rimer: “Formation of GaN in Chabazite by Scavenging Framework Gallium”, In Preparation.

[2] Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer: “Selective Production of Para-Xylene from Biomass-derived 2,5-Dimethylfuran through Tandem Diels Alder/Dehydration Reactions with a Bifunctional Ga,Al Zeolite Catalyst”, Invited for special issue: Celebration of Klavs Jensen’s 70th Birthday, React. Chem. Eng., 9 (2024) 3277-3284.

[3] Amir Abutalib, Deependra Parma, Jaeyul Kim, Jeffrey D. Rimer: “Pairing Ga/Al-Zeolites with Tailored Acidity as Tandem Catalysts for the Conversion of Alcohols to Olefins”, J. Catal., 433 (2024) 115466.

Research Interests

Development of Heterogeneous Catalysts for Hydrocarbon Conversion in the Petroleum and Petrochemical Industry

• Catalyst Types:
  • Metal-incorporated zeolite catalysts
  • Noble metal alloy-supported egg-shell-structured catalysts
  • Powder/film type of mixed metal oxide catalysts
  • Metal-substituted mesoporous materials
  • Noble/transition metal-loaded/doped catalysts
• Target Reactions:
  • Catalytic cracking
  • Reforming
  • Hydrotreating
  • Aromatization
  • Dehydrogenation

Industrial Experience

2019 – 2020 Principal Research Scientist, Catalyst R&D, Catalyst Division, Petrochemicals, LG Chem Ltd., Republic of Korea (Korea)

• Development of Heterogeneous Catalyst for Selective Hydrogenation of Hydrocarbon Feedstocks

2014 – 2019 Professional, Petrochemicals R&D, LG Chem Ltd., Korea

• Development of SAP (super absorbent polymer) Production Process
• Development of Bio-Polymer (isosorbide-PC)

2006 Summer Internship, Hynix Semiconductor Inc. (now merged to SK Hynix Inc.), Korea

Honors and Awards

2024 Poster Award (2nd place), 2024 Welch Conference, Houston, TX

2024 Poster Prize Winner, 3rd Texas Porous Engineering Conference (TEXPEC2024), Houston, TX

2021-2023 Presidential Fellowship, University of Houston, Houston, TX

2011 Prize (Next to Bronze), 17th Human Tech Thesis Prize, Samsung Electronics Co. Ltd., Korea

Technical Skills

Inorganic Heterogeneous Catalyst Synthesis: metal-incorporated zeolite catalyst, noble metal alloy-supported egg-shell-structured catalyst, powder/film type of mixed metal oxide catalyst, metal-substituted mesoporous materials, noble/transition metal-loaded/doped catalyst, synthesized by impregnation, hydrothermal/sol-gel, solid state mixing, spray/spin/doctor blade-coating methods

Reaction System Design, Set-up, Operation and Maintenance: liquid phase batch reaction system running at high pressure for selective production of aromatic compound, lab./bench-scale multiple channel continuous flow catalytic reaction system running at high pressure for selective hydrogenation of hydrocarbon, continuous flow reaction system for photocatalytic partial oxidation of dodecane (diesel fuel oil)

Characterizations Demonstrated by Publications/patents: XAFS (XANES), SAXS, XRD, XPS, ICP, SEM, TEM, OM, BET, N₂-isotherm, H₂/O₂/CO/NH₃-TPO/TPR/TPD, GC-MS, FTIR, DRIFT, UV-Vis DRS spectroscopy

Polymerization Process: bio-based isosorbide-PBT/PC polymerization and characterizations (Tg (glass transition temperature, DSC (Differential scanning calorimetry), Mw (molecular weight), tensile strength, surface hardness), SAP (super absorbent polymer) polymerization (radical/emulsion polymerization) and characterizations (centrifuge retention capacity, extractable contents, residual monomer, vortex, bulk density and other related characteristics)

Presentations and Posters

2025 Southwest Catalysis Society Spring Symposium, Houston, TX

• Jaeyul Kim, Sunkyu Kim, Seungwan Seo, Raul F. Lobo, Jeffrey D. Rimer, GaN Formation in CHA Zeolite through Framework Gallium Scavenging

2024 AICHE Annual Meeting, San Diego, CA

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Selective Production of Para-Xylene from Biomass-Derived 2,5-Dimethylfuran through Tandem Diels–Alder/Dehydration Reactions with Bifunctional Zeolite Catalysts (Oral)

2024 AICHE Annual Meeting, San Diego, CA

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Tuning Acidity of Beta Zeolite through Heteroatom Incorporation for Efficient Para-Xylene Production in Liquid-Phase Conversion of Biomass-Derived Resource

2024 Welch Conference “FRONTIERS IN MOLECULAR CATALYSIS”, Houston, TX

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, One-pot Synthesis of Ga,Al-*BEA Zeolites as Novel Catalysts for Upgrading Biomass to Value-added Chemicals Reaction

2024 3rd Texas Porous Engineering Conference, Houston, TX

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Isomorphic Substitution of Framework Ga in Beta Zeolite for Enhanced p-Xylene Selectivity in a Biomass Conversion

2024 39th Annual Organization of Chemical Engineering Graduate Students Research Symposium, Houston, TX

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Engineering Bifunctional Zeolite Beta Catalysts for Enhanced p-Xylene Selectivity in the Diels-Alder/dehydration Reaction

2024 Southwest Catalysis Society Spring Symposium, Houston, TX

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Selective Production of Para-Xylene from Biomass-derived 2,5-Dimethylfuran through Tandem Diels–Alder/Dehydration Reactions with Bifunctional Zeolite Catalysts

2023 38th Annual Organization of Chemical Engineering Graduate Students Research Symposium, Houston, TX

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Selective Catalytic Production of Renewable Para-Xylene by Tandem Diels–Alder/Dehydration Reactions with a Bifunctional Ga,Al-*BEA Catalyst

2023 Southwest Catalysis Society Spring Symposium, Houston, TX

• Jaeyul Kim, Sungmin Han, Jeffrey D. Rimer, Incorporation of Ga in Zeolite Beta for Renewable Para-Xylene Production

Teaching Experience (Graduate Teaching Assistant)

Spring 2025 Topics in Colloids and Interface Science (CHEE6322)

• Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX

Spring 2024 Chemical Engineering Transport Processes (CHEE3369)

• Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX

Spring 2023 Chemical Engineering Transport Processes (CHEE3369)

• Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX

Spring 2022 Chemical Engineering Transport Processes (CHEE3369)

• Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX