Global research trends in biodiesel production from palm fatty acid distillate (PFAD) using CaO, MgO, and TiO2 heterogeneous catalysts: a bibliometric analysis (2015-2025)
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Keywords:
Biodiesel production, Palm fatty acid distillate, Heterogeneous catalysts, Renewable energy, Bibliometric analysis
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Abstract
This bibliometric study provides a comprehensive of global research on biodiesel production from palm fatty acid distillate (PFAD) using heterogeneous CaO, MgO, and TiO2 catalysts during the period of 2015–2025. A total of 179 Scopus-indexed documents were analyzed by means of VOSviewer to examine publication trends, citation impact, co-authorship networks, and keyword co-occurrence. It is evident that Malaysia, Thailand, and Indonesia dominate both the publications and citations, reflecting their dominant palm oil production capacity. A substantial proportion of publications is concentrated on high-impact journals in the fields of energy and chemical engineering. A keyword clustering analysis reveals five main themes: process optimization, catalyst synthesis (including waste-derived CaO), feedstock diversification, activation/intensification techniques, and sustainability. The results demonstrate a predominance of laboratory-scale studies employing waste-based oxides, with a paucity of research addressing pilot-scale implementation, techno-economic assessment, and life cycle analysis. The findings provide a strategic roadmap for researchers, policymakers, and industry stakeholders to prioritize future developments in PFAD-based biodiesel production, particularly in catalyst scale-up, techno-economic assessment, and sustainable process integration. The primary benefit of this study is its capacity to systematically consolidate a decade of disparate research into a structured analytical framework, thereby enabling more targeted investment in under-explored areas such as pilot-scale implementation and life cycle analysis. In turn, this is expected to accelerate the transition of PFAD-based biodiesel from laboratory research to industrial application.
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Syam, S. R. M., Budiyono, B., & Hadiyanto, H. (2026). Global research trends in biodiesel production from palm fatty acid distillate (PFAD) using CaO, MgO, and TiO2 heterogeneous catalysts: a bibliometric analysis (2015-2025). Communications in Science and Technology, 11(1), 82–99. https://doi.org/10.21924/cst.11.1.2026.1878
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References
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7. Aria M, Cuccurullo C. bibliometrix: An R-tool for comprehensive science mapping analysis. J. Informetr. (2017);11.
8. Mongeon P, Paul-Hus A. The journal coverage of Web of Science and Scopus: a comparative analysis. Scientometrics (2016);106.
9. Donthu N, Kumar S, Mukherjee D, Pandey N, Lim WM. How to conduct a bibliometric analysis: An overview and guidelines. J. Bus. Res. (2021);133.
10. van Eck NJ, Waltman L. Software survey: VOSviewer, a computer program for bibliometric mapping. Scientometrics. (2010);84:523-538.
11. van Eck NJ, Waltman L. Visualizing Bibliometric Networks. In: Ding Y, Rousseau R, Wolfram D, editors. Measuring Scholarly Impact. Cham: Springer; (2014). p. 285-320.
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13. Sterner E. Cleaning collections data using OpenRefine. Issues Sci. Technol. Libr. (2019).
14. Zupic I, Čater T. Bibliometric Methods in Management and Organization. Organ. Res. Methods. (2015);18:429-472.
15. Bornmann L, Daniel HD. What do citation counts measure? A review of studies on citing behavior. J. of Doc. (2008);64.
16. Garfield E. The history and meaning of the journal impact factor. JAMA. (2006);295.
17. Wagner CS, Roessner JD, Bobb K, Klein JT, Boyack KW, Keyton J, et al. Approaches to understanding and measuring interdisciplinary scientific research (IDR): A review of the literature. J. Informetr. (2011);5.
18. Abdullah B, Syed Muhammad SAF ad, Shokravi Z, Ismail S, Kassim KA, Mahmood AN, et al. Fourth generation biofuel: A review on risks and mitigation strategies. Renew. Sustain. Energy Rev. (2019);107.
19. Atabani AE, Silitonga AS, Badruddin IA, Mahlia TMI, Masjuki HH, Mekhilef S. A comprehensive review on biodiesel as an alternative energy resource and its characteristics. Renew. Sustain. Energy Rev. (2012);16.
20. Lam MK, Lee KT, Mohamed AR. Homogeneous, heterogeneous and enzymatic catalysis for transesterification of high free fatty acid oil (waste cooking oil) to biodiesel: A review. Biotechnol. Adv. (2010);28.
21. International Energy Agency (IEA), Renewables 2019: Market analysis and forecast from 2019 to 2024, IEA, Paris, (2019).
22. Boey PL, Maniam GP, Hamid SA, Ali DMH. Utilization of waste cockle shell (Anadara granosa) in biodiesel production from palm olein: Optimization using response surface methodology. Fuel (2011);90.
23. Granados ML, Poves MDZ, Alonso DM, Mariscal R, Galisteo FC, Moreno-Tost R, et al. Biodiesel from sunflower oil by using activated calcium oxide. Appl. Catal. B Environ. (2007);73.
24. Endalew AK, Kiros Y, Zanzi R. Heterogeneous catalysis for biodiesel production from Jatropha curcas oil (JCO). Energy (2011);36.
25. Abdul Kapor NZ, Maniam GP, Rahim MHA, Yusoff MM. Palm fatty acid distillate as a potential source for biodiesel production-a review. J. Clean Prod. (2017);143.
26. Mahlia TMI, Ismail N, Hossain N, Silitonga AS, Shamsuddin AH. Palm oil and its wastes as bioenergy sources: a comprehensive review. Environ. Sci. Pollut. Res. (2019);26.
27. Hirsch JE. An index to quantify an individual’s scientific research output. Proc. Natl Acad Sci. USA (2005);102.
28. Ibrahim NA, Rashid U, Hazmi B, Moser BR, Alharthi FA, Rokhum SL, et al. Biodiesel production from waste cooking oil using magnetic bifunctional calcium and iron oxide nanocatalysts derived from empty fruit bunch. Fuel (2022);317.
29. Cho HJ, Kim JK, Ahmed F, Yeo YK. Life-cycle greenhouse gas emissions and energy balances of a biodiesel production from palm fatty acid distillate (PFAD). Appl. Energy (2013);111.
30. Muskhir M, Luthfi A, Watrianthos R, Usmeldi, Fortuna A, Samala AD. Emerging Research on Virtual Reality Applications in Vocational Education: A Bibliometric Analysis. J. Inf. Technol. Educ. Innov. Pract. (2024);23.
31. Das S, Kaushik B, Chaudhury AP, Basumatary S, Pratap P, Mohan S, et al. Microwave-assisted biodiesel production from WCO using snail shell-derived CaO@Coal fly ash: Optimization via RSM, cost analysis, kinetics, thermodynamics, and bibliometrics. Renew. Energy (2025);254.
32. Tahvildari K, Anaraki YN, Fazaeli R, Mirpanji S, Delrish E. The study of CaO and MgO heterogenic nano-catalyst coupling on transesterification reaction efficacy in the production of biodiesel from recycled cooking oil. J. Environ. Health Sci. Eng. (2015);13.
33. Widayat, Satriadi H, Setyojati PW, Shihab D, Buchori L, Hadiyanto H, et al. Preparation CaO/MgO/Fe3O4 magnetite catalyst and catalytic test for biodiesel production. Results Eng. (2024);22.
34. Awogbemi O, Ojo AA, Adeleye SA. Advancements in the application of metal oxide nanocatalysts for sustainable biodiesel production. Discover Appl. Sci. (2024);6.
35. Ong HC, Mahlia TMI, Masjuki HH, Norhasyima RS. Comparison of palm oil, Jatropha curcas and Calophyllum inophyllum for biodiesel: A review. Renew. Sustain. Energy Rev. (2011);15.
36. Waltman L, van Eck NJ, Noyons ECM. A unified approach to mapping and clustering of bibliometric networks. J. Informetr. (2010);4.
37. Ruhul AM, Kalam MA, Masjuki HH, Fattah IMR, Reham SS, Rashed MM. State of the art of biodiesel production processes: A review of the heterogeneous catalyst. RSC Adv. (2015);5.
38. Sulaiman NF, Gunasekaran SS, Zaman HB, Nashruddin SNAM, Nashruddin SNAM, Sofiah AGN, et al. Advances in catalysis for biodiesel production: Integrating AI-driven optimization and bibliometric insights into renewable energy technologies. Bioresour Technol. (2025);437.
39. Ooi HK, Koh XN, Ong HC, Lee HV, Mastuli MS, Taufiq-Yap YH, et al. Progress on modified calcium oxide derived waste-shell catalysts for biodiesel production. Catalysts. (2021);11.
40. Cirujano FG, Dhakshinamoorthy A. Engineering of Active Sites in Metal–Organic Frameworks for Biodiesel Production. Adv. Sustain. Syst. (2021);5.
41. Amal R, Nadeem R, Intisar A, Rouf H, Hussain D, Kousar R. An insight into the catalytic properties and process optimization of Fe, Ni doped eggshell derived CaO for a green biodiesel synthesis from waste chicken fat. Catal. Commun. (2024);187.
42. Khemthong P, Luadthong C, Nualpaeng W, Changsuwan P, Tongprem P, Viriya-Empikul N, et al. Industrial eggshell wastes as the heterogeneous catalysts for microwave-assisted biodiesel production. Catal. Today. (2012);190.
43. Ao S, Gouda SP, Selvaraj M, Boddula R, Al-Qahtani N, Mohan S, et al. Active sites engineered biomass-carbon as a catalyst for biodiesel production: Process optimization using RSM and life cycle assessment. Energy Convers. Manag. (2024);300.
44. Manojkumar N, Muthukumaran C, Sharmila G. A comprehensive review on the application of response surface methodology for optimization of biodiesel production using different oil sources. J. King Saud Univ. Eng. Sci. (2022);34.
45. Rizwanul Fattah IM, Ong HC, Mahlia TMI, Mofijur M, Silitonga AS, Ashrafur Rahman SM, et al. State of the Art of Catalysts for Biodiesel Production. Front Energy Res. (2020);8.
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