DOI: https://doi.org/10.14710/jksa.29.9.581-589

Hydrothermal Conversion of Glycerol over Cu-Modified Acid-Activated Natural Zeolite: Effect of Cu Loading and Reaction Time on Catalytic Performance

Department of Chemical Engineering, Faculty of Engineering, Universitas Sebelas Maret, Jl. Ir. Sutami No.36A, Surakarta, 57126, Indonesia

Received: 10 Jun 2026; Revised: 2 Sep 2026; Accepted: 25 Sep 2026; Published: 30 Oct 2026.
Open Access Copyright 2026 Jurnal Kimia Sains dan Aplikasi under http://creativecommons.org/licenses/by-sa/4.0.

Citation Format:
Cover Image
Abstract

The conversion of glycerol into value-added chemicals represents an attractive approach for improving the economic sustainability of biodiesel production. In this study, Cu-modified acid-activated natural zeolite (Cu-ANZ) catalysts were prepared and evaluated for hydrothermal glycerol conversion, with particular attention to the formation of a product tentatively assigned to lactic acid based on its HPLC retention time relative to that of a lactic acid standard. Natural zeolite was activated using hydrochloric acid and subsequently modified by Cu impregnation at loadings of 2.5–15 wt%. The catalysts were characterized using FTIR, XRD, SEM-EDX, and BET analyses, while the reaction products were analyzed by HPLC after hydrothermal conversion of glycerol at 230°C in the presence of NaOH. FTIR and XRD analyses indicated that the modification treatments altered the physicochemical properties of the natural zeolite while preserving its fundamental structural features and crystallinity. SEM-EDX analysis confirmed the presence of Cu in the modified catalyst and showed a higher Si/Al ratio for Cu-ANZ than for the untreated natural zeolite. BET analysis showed that the surface area increased from 27.010 to 32.826 m2 g−1 after the overall modification process. The relative HPLC peak area (RHPA) increased with Cu loading up to 10 wt%, reaching its maximum, then decreased at higher Cu loadings. Investigation of reaction time showed an increase in the RHPA with longer reaction durations, with a pronounced increase observed between 100 and 180 min and the highest value observed at 300 min. These findings indicate that Cu loading and reaction time influence the relative HPLC response associated with the product tentatively assigned to lactic acid during hydrothermal glycerol conversion and provide insights into the potential application of Cu-modified acid-activated natural zeolite in this reaction.

Fulltext View|Download Email colleagues
Keywords: Glycerol conversion; Lactic acid; Natural zeolite; Copper catalyst; Hydrothermal catalysis
Funding: GR-UNS research scheme under contract 228/UN27.22/PT.01.03/2023

Article Metrics:

Article Info
Section: Research Articles
Language : EN
Most cited articles
Sintesis dan Karakterisasi Zeolit Y Analisis Pangan: Penentuan Angka Peroksida dan Asam Lemak Bebas pada Minyak Kedelai dengan Variasi Menggoreng Pengolahan Limbah Cair Industri Batik dengan Metoda Elektrokoagulasi Menggunakan Besi Bekas Sebagai Elektroda Konsentrasi Hambat Minimum (KHM) Kadar Sampel Alang-Alang (Imperata cylindrica) dalam Etanol Melalui Metode Difusi Cakram Sintesis Lempung Terpilar Polikation Alumunium Sebagai Adsorben Indigo Karmina More cited articles
  1. Zixuan Wang, Yuming Zhang, Yanan Wang, Jiazhou Li, Xicheng Jia, Zhijie Wu, Recent progress in glycerol oxidation to lactic acid and pyruvic acid with heterogeneous metal catalysts, Carbon Resources Conversion, 8, 2, (2025), 100250 https://doi.org/10.1016/j.crcon.2024.100250
  2. Haixu Yin, Changhua Zhang, Hengbo Yin, Dezhi Gao, Lingqin Shen, Aili Wang, Hydrothermal conversion of glycerol to lactic acid catalyzed by Cu/hydroxyapatite, Cu/MgO, and Cu/ZrO2 and reaction kinetics, Chemical Engineering Journal, 288, (2016), 332-343 https://doi.org/10.1016/j.cej.2015.12.010
  3. Nur Hidayati, Rahmah Puspita Sari, Herry Purnama, Catalysis of glycerol acetylation on solid acid catalyst : a review, Jurnal Kimia Sains dan Aplikasi, 23, 12, (2020), 414-423 https://doi.org/10.14710/jksa.23.12.414-423
  4. José L.C. Fajín, M. Natália D.S. Cordeiro, Glycerol conversion into added-value products on Ni-Cu based catalysts: Investigating mechanistic variations via catalyst modulation, Molecular Catalysis, 561, (2024), 114168 https://doi.org/10.1016/j.mcat.2024.114168
  5. C. S. Fronza, H. Enzweiler, N. P. G. Salau, Valorization of biodiesel-derived glycerol into fuel additives: advances in esterification, etherification, and ketalization using sulfonated catalysts, Fuel, 420, (2026), 138867 https://doi.org/10.1016/j.fuel.2026.138867
  6. Asma Ghorbani, Venu Babu Borugadda, Ajay K. Dalai, Exploring catalytic pathways for glycerol valorization into 1,3-propanediol: A review on hydrogenolysis, Renewable and Sustainable Energy Reviews, 224, (2025), 116054 https://doi.org/10.1016/j.rser.2025.116054
  7. Cheng Tang, Shuangming Li, Shanqi Li, Yiwen Wang, Sansan Yu, Selective catalytic conversion of glycerol to lactic acid over CuO-NiO complex oxides, Molecular Catalysis, 553, (2024), 113804 https://doi.org/10.1016/j.mcat.2023.113804
  8. Anil H. Valekar, Macchindra G. Chandgude, Hyun-Wook Jeong, Kyung-Ryul Oh, Young Kyu Hwang, Glycerol conversion to lactate over Pt/Ce-ZrO2 catalysts: Support doping effects on product selectivity and catalyst stability, Chemical Engineering Journal, 523, (2025), 168525 https://doi.org/10.1016/j.cej.2025.168525
  9. K. C. Sembiring, A. Kristiani, L. N. Hidayati, S. Sudiyarmanto, F. Aulia, A. Aunillah, MgO-supported Ni-Sn Catalysts: Characterization and Catalytic Properties for Aqueous-phase Catalytic Reforming of Glycerol, Jurnal Kimia Sains dan Aplikasi, 24, 6, (2025), 200-205 https://doi.org/10.14710/jksa.24.6.200-205
  10. E. B. Santiko, S. Fauziah, S. Priyanto, Y. Yustinah, L. Marlinda, S. Sudibyo, A. Aziz, P. Oktiarmi, I. Yati, M. Al Muttaqii, Nickel-Lanthanum Impregnated into Natural Zeolite as a Catalyst for Biofuel Production from Sunflower Oil via Hydrocracking Process, Bulletin of Chemical Reaction Engineering & Catalysis, 21, 1, (2026), 68-79 https://doi.org/10.9767/bcrec.20503
  11. Aya Sandid, Vincenzo Spallina, Jesús Esteban, Glycerol to value-added chemicals: State of the art and advances in reaction engineering and kinetic modelling, Fuel Processing Technology, 253, (2024), 108008 https://doi.org/10.1016/j.fuproc.2023.108008
  12. Noraini Razali, Ahmad Zuhairi Abdullah, Production of lactic acid from glycerol via chemical conversion using solid catalyst: A review, Applied Catalysis A: General, 543, (2017), 234-246 https://doi.org/10.1016/j.apcata.2017.07.002
  13. Mehmet Melikoglu, Recent advancements in lactic acid production from food and other biowastes: A global review of biorefinery strategies and circular economy, Food Humanity, 6, (2026), 100965 https://doi.org/10.1016/j.foohum.2025.100965
  14. Xinshu Xie, Shuangming Li, Sansan Yu, Selective oxidation of glycerol to lactic acid catalyzed by MOF-74 (Cu/Co) derived Cu/Cu2O/CoO@C nanocomposites, Applied Catalysis O: Open, 211, (2026), 207086 https://doi.org/10.1016/j.apcato.2026.207086
  15. Xinshu Xie, Shuangming Li, Hanqu Fu, Yiwen Wang, Feng Chen, Shuang Ren, Jili Zhang, Sansan Yu, Selective oxidation of glycerol to lactic acid catalyzed by Cu-based MOFs, Molecular Catalysis, 583, (2025), 115209 https://doi.org/10.1016/j.mcat.2025.115209
  16. Han Xu, Qi Li, Zhihao Bi, Donghai Xu, Yang Guo, Sustainable lactic acid production from glycerol via hydrothermal catalysis over highly dispersed cu nanoparticles on bio-tar derived carbon, Journal of Environmental Chemical Engineering, 13, 6, (2025), 119275 https://doi.org/10.1016/j.jece.2025.119275
  17. Syamima Nasrin Mohamed Saleh, Muhammad Yusri Ahmad, Anwar Ul-Hamid, Ahmad Zuhairi Abdullah, Elucidation of synergism in Ce-Zr/SBA-15 mesoporous catalysts and the effects on the activity in selective glycerol to lactic acid reaction, Powder Technology, 444, (2024), 120048 https://doi.org/10.1016/j.powtec.2024.120048
  18. Nidhi Yadav, Gaurav Yadav, Md. Ahmaruzzaman, Catalytic conversion and mechanism of glycerol into various value-added products : A critical review, Industrial Crops and Products, 210, (2024), 117999 https://doi.org/10.1016/j.indcrop.2023.117999
  19. Junjie Zhang, Guozhi Zhu, Xi Wang, Yuliang Mai, Jiazhi Chen, Selective catalytic conversion of glycerol to lactic acid over Cu-ZnO@C catalysts, Catalysis Communications, 181, (2023), 106733 https://doi.org/10.1016/j.catcom.2023.106733
  20. Isalmi Aziz, Purwantiningsih Sugita, Noviyan Darmawan, Adid Adep Dwiatmoko, Effect of desilication process on natural zeolite as Ni catalyst support on hydrodeoxygenation of palm fatty acid distillate (PFAD) into green diesel, South African Journal of Chemical Engineering, 45, (2023), 328-338 https://doi.org/10.1016/j.sajce.2023.07.002
  21. Suyitno, Imron Rosyadi, Zainal Arifin, Tata Sutardi, Sunaryo, Nasrul Ilminnafik, Advanced modification of natural zeolites for optimized biogas, syngas, and hydrogen production and purification, Cogent Engineering, 11, 1, (2024), 2398912 https://doi.org/10.1080/23311916.2024.2398912
  22. Mudasir Zahid, Yerlan Doszhanov, Karina Saurykova, Noorahmad Ahmadi, Didar Bolatova, Meruyert Kurmanbayeva, Akbope Aydarbek, Rahmuddin Ihsas, Makpal Seitzhanova, Dana Akhmetzhanova, Almagul Kerimkulova, Ospan Doszhanov, Modification and Application of Natural Clinoptilolite and Mordenite from Almaty Region for Drinking Water Purification, Molecules, 30, 9, (2025), https://doi.org/10.3390/molecules30092021
  23. Sandugash Tanirbergenova, Dildara Tugelbayeva, Nurzhamal Zhylybayeva, Aizat Aitugan, Kairat Tazhu, Gulya Moldazhanova, Zulkhair Mansurov, Effect of Acid Treatment on the Structure of Natural Zeolite from the Shankhanai Deposit, Processes, 13, 9, (2025), 2896 https://doi.org/10.3390/pr13092896
  24. Qiang Ling, Shuai Zhang, Liye Yang, Rong Wu, Rui Zhu, Zhao Lei, Xiang-chun Liu, Ping Cui, Carbon-doped and coated Cu/13X zeolite molecular composite for enhanced catalytic degradation of p-nitrophenol: Promotion role of metal migration during co-pyrolysis process, Microporous and Mesoporous Materials, 406, (2026), 114087 https://doi.org/10.1016/j.micromeso.2026.114087
  25. Han Han, Yuqing Tang, Guangying Huang, Xilai Yan, Jie Xie, Hongshen He, Weijie Lin, Ajoy Kanti Mondal, Shibo Han, Fang Huang, Preparation of Cu-loaded porous metal oxide catalysts for the catalytic upgrading of wood tar in supercritical methanol, Fuel, 415, (2026), 138499 https://doi.org/10.1016/j.fuel.2026.138499
  26. Billy Joy Vargas, Juliano Rosa de Menezes Vicenti, Edilene Deise da Silva, Alexandre H. Pinto, Luiz Fernando Gorup, Cezar Augusto da Rosa, Vanessa Bongalhardo Mortola, Glycerol valorization: The effect of Cu on the HZSM5 catalyst structure and increased selectivity towards allyl alcohol, Chemical Engineering Research and Design, 196, (2023), 617-631 https://doi.org/10.1016/j.cherd.2023.06.061
  27. Gao-yuan Yang, Yi-hu Ke, Hui-fang Ren, Chun-ling Liu, Rong-zhen Yang, Wen-sheng Dong, The conversion of glycerol to lactic acid catalyzed by ZrO2-supported CuO catalysts, Chemical Engineering Journal, 283, (2016), 759-767 https://doi.org/10.1016/j.cej.2015.08.027
  28. R. González-Pizarro, S. Renda, J. Lasobras, J. Soler, M. Menéndez, J. Herguido, Low loading copper-based catalysts for effective CO2 hydrogenation to methanol, Fuel, 408, (2026), 137642 https://doi.org/10.1016/j.fuel.2025.137642
  29. Do Trung Hieu, Hendrik Kosslick, Muhammad Riaz, Axel Schulz, Armin Springer, Marcus Frank, Christian Jaeger, Nguyen Thi Minh Thu, Le Thanh Son, Acidity and Stability of Brønsted Acid Sites in Green Clinoptilolite Catalysts and Catalytic Performance in the Etherification of Glycerol, Catalysts, 12, 3, (2022), 253 https://doi.org/10.3390/catal12030253
  30. Lydia Anggraini, Waqar Hussain, Kadek Dharmayudha Aryaputra, Syed Abdul Moiz Hashmi, Serene Lock Sow Mun, Hadiyawarman, Mahardika Fahrudin Rois, Synthesis, binder optimization, and physicochemical characterization of activated carbon-zeolite-magnetite composites, Journal of the Indian Chemical Society, 103, 5, (2026), 102601 https://doi.org/10.1016/j.jics.2026.102601
  31. Fatima Elgharbi, Fida Baragh, Tao Hu, Satu Ojala, Rachid Brahmi, Anne Heponiemi, Mahfoud Agunaou, Sustainable CuO-impregnated NaX zeolite derived from natural bentonite clay for enhanced catalytic wet peroxide oxidation of rhodamine B dye, Surfaces and Interfaces, 93, (2026), 109416 https://doi.org/10.1016/j.surfin.2026.109416
  32. Leila Farajzadeh, Amin Salem, Shiva Salem, Characterization of zeolite 4A produced based on combined fusion-hydrothermal technique from PAHs-contaminated aluminosilicate collected in oil refinery landfill, Polyhedron, 293, (2026), 118087 https://doi.org/10.1016/j.poly.2026.118087
  33. J. L. Sihombing, E. Ginting, S. Amdayani, A. N. Pulungan, Tanjung V., A. A. Sandy, R. Rahayu, Characterization of sarulla natural zeolite activated with various acid concentration and loaded with Ni and Ni-Mo metals as bifunctional catalysts, Journal of Physics: Conference Series, 2193, (2022), 012081 https://doi.org/10.1088/1742-6596/2193/1/012081
  34. Xiuzhen Xie, Changqing Tong, One-pot synthesis of Cu²⁺-doped 4A zeolite from kaolin: Structural characterization and functional potential analysis, Results in Engineering, 29, (2026), 108673 https://doi.org/10.1016/j.rineng.2025.108673
  35. Bihong Li, Yijie Ding, Weizhong Zheng, Weizhen Sun, Ling Zhao, Enhanced catalytic performance of low-Si/Al-ratio beta-zeolite modified by La/Cu on C4 alkylation, Chemical Engineering Science, 321, (2026), 122741 https://doi.org/10.1016/j.ces.2025.122741
  36. Aolue Yan, Yanhong Quan, Yan Li, Jun Ren, Fabrication of highly efficient Cu catalysts supported on dealuminated Y zeolite for the methanol dehydrogenation reaction, Fuel, 417, (2026), 138649 https://doi.org/10.1016/j.fuel.2026.138649

Last update:

No citation recorded.

Last update: 2026-11-05 16:22:06

No citation recorded.