Comparative analysis of methods for determining total acid number in oil and derivatives from a sustainability perspective

Authors

DOI:

https://doi.org/10.21712/lajer.2025.v12.n3.p1-9

Keywords:

Petroleum, Sustainability, Analytical Methods, Green Chemistry, Multicriteria Assessment

Abstract

The Total Acidity Number (TAN) is a critical parameter in the evaluation of the quality of petroleum and derivatives, influencing refining processes, equipment corrosivity and maintenance costs. Traditionally, classical colorimetric, potentiometric, and thermometric methods, such as ASTM D974, ASTM D664, and ABNT NBR 14448, have been widely used due to their simplicity and reliability. However, these methods have high consumption of organic solvents and waste generation, as well as limitations regarding accuracy in complex matrices. Thus, the objective of this work was to comparatively analyze the main methods of determining TAN in petroleum and derivatives, considering analytical efficiency and sustainability criteria, through the Sustainability Degree Assessment (GS). A systematic survey was carried out (Scielo, Web of Science, Scopus and Google Scholar) and sustainability was evaluated by Multicriteria Analysis (MCDA) in three criteria: Environmental (weight 0.5), Economic (0.3) and Social/Operational (0.2) with a score from 1 to 5. The SG was calculated by weighted average and classified as low (GS<2.0), medium (2.0≤GS<3.5) and high (GS≥3.5). The results showed that the colorimetric methods have low sustainability (SG between 2.85 and 3.25), while the classical potentiometric methods have medium sustainability (SG between 2.65 and 3.05). The Micellar Solubilization Nanoemulsion (MSN) method stood out as a promising alternative, reaching GS=3.60 and being classified as highly sustainable. The ASTM D8045 thermometric method obtained GS=3.30, configuring itself as an intermediate technology. It was concluded, therefore, that the colorimetric methods presented lower sustainability (high use of solvents and subjectivity), while the classical potentiometric methods had intermediate performance, with the MSN method being the most sustainable and robust, while the thermometric method is the intermediate.

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Author Biographies

  • Flaviane Mendonça Ambrozim, CEUNES/ UFES

    She holds a degree in Chemical Engineering from the Federal University of Espírito Santo (CEUNES/UFES) (2015) and a master's degree in Chemical Engineering from the Federal University of Espírito Santo (CCAE/UFES) (2019). She is currently a doctoral student in the Energy Postgraduate Program at the Federal University of Espírito Santo (PPGEN/CEUNES/UFES) and works as a laboratory technician in the chemistry laboratories of the Department of Natural Sciences (DCN/CEUNES/UFES).

  • Raquel Vieira, CEUNES/ UFES
                    329       Graduated in Chemistry from the Federal University of Minas Gerais (UFMG), currently a master's student in the Postgraduate Program in Energy at the Federal University of Espírito Santo (UFES), with a research focus on Petroleum, Gas, and Renewable Energies. She develops studies in the area of ​​Petroleum Chemistry, with an emphasis on instrumental analysis.
  • Lucimara R. Venial, CEUNES/ UFES

    Graduated in Agronomy from the Federal University of Espírito Santo (2016), Master's degree in Plant Production from the same institution (2019), and PhD in Agronomy from the Federal University of Ceará (2024), with a sandwich doctorate at the University of Cagliari, Italy. Experience in Biotechnology and Ecophysiology of Plant Development, with emphasis on seeds and tissue culture, and work in computer vision associated with deep learning techniques. Currently a Postdoctoral Fellow at the Federal University of Espírito Santo, working on the development and comparison of multivariate calibration models and in language processing approaches with machine learning algorithms.

  • Luana N. Zanelato, PhD in Chemistry - UFES

    She holds a degree in Chemical Engineering from the Federal University of Espírito Santo (2015), a master's degree in Energy from the Federal University of Espírito Santo (2018), and a doctorate in Chemistry from the Federal University of Espírito Santo (2025), working mainly on the following topics: oil-in-water and water-in-oil emulsions; ultrasound; petroleum; droplet diameter; micellar solubilization; acidity and chlorides.

  • Maristela de A. Vicente, CEUNES/ UFES

    She holds a degree in Pharmacy from the Federal University of Ouro Preto (1992), a master's degree in Biological Sciences from the Federal University of Ouro Preto (2003), and a doctorate in Biological Sciences from the Federal University of Ouro Preto (2007). She is currently an Associate Professor at the Federal University of Espírito Santo, located in the Department of Natural Sciences. She teaches Analytical Chemistry and Instrumental Analysis. She has experience in the field of Analytical Chemistry, with an emphasis on Analytical Instrumentation, working mainly on the following topics: sample preparation, petroleum, ultrasound, water, and remediation. She holds 3 national and 1 international innovation patents.

  • Maria de Fátima P. dos Santos, CEUNES/ UFES

    She holds a Bachelor's degree in Chemistry with a Technological Orientation (1990), a Licentiate degree in Chemistry (1991), and advanced training in Higher Education Teaching Methodology (1995) from the Souza Marques Technical Educational Foundation. She also holds advanced training in Petroleum Engineering from Estácio de Sá University (2001), a Master's degree in Analytical Chemistry from the Federal University of Rio de Janeiro (2004), and a Doctorate in Analytical Chemistry from the Federal University of Santa Maria (2009). She has been a technical and higher education professor in private institutions since 1991. She was a Chemistry Technician and Chemist in the Refining Management and a researcher in the Primary Processing and Petroleum Evaluation Management at the Leopoldo Américo Miguez de Mello Research and Development Center since 1992. She was a consultant on Brazilian Technical Standards Association standards in the committee for the study of fuels and special products. She participated in working groups in the area of ​​method precision and quality according to ISO 17025 at the Brazilian Institute of Petroleum, Gas and Biofuels since 2000. She participated in research projects integrating Petrobras S.A. and the following universities: UFRJ, UFMA, UFSM, UFPI, UFRN and UNIT. Currently, she is a Full Professor of Analytical Petroleum Chemistry. She coordinated the Postgraduate Program in Energy at the Federal University of Espírito Santo from 2016 to 2017. She has experience in the area of ​​Petroleum Chemistry, with emphasis on quality control, method validation and characterization using physicochemical measurement techniques, combustion, solvent extraction, gravimetric, potentiometric, X-ray fluorescence, infrared, ultraviolet, chemiluminescence and thermogravimetry. She is a permanent member of the PPGEN, Master's program in ENERGY, research line in Petroleum, gas and renewable energies. She works primarily on the study of the following topics: behavior of mixtures and determination of solubility parameters in Brazilian crude oils, use of alternative microwave and ultrasound energies in the separation of heavy crude oil emulsions, and the development, optimization, and validation of methods for the characterization of extra-heavy crude oils, development of methods for the determination of dielectric and electrical properties in crude oils and crude oil emulsions. On November 10, 2016, she was honored by the Laboratory of Industrial and Environmental Chemical Analysis of the Federal University of Santa Maria for encouraging research and supporting CEPETRO. She holds four patent grants and eight patent applications for technological innovation in the oil industry. Of particular note is the approval by the Federal University of Espírito Santo, included in the 5th and 10th patents published by the National Institute of Industrial Property (INPI). The invention of the 10th published patent refers to the use of ultrasonic waves in a sustainable process for recovering base oil from used lubricating oil, with less impact on the environment. In June 2024, I was nominated to be part of the Advisory Committee for Productivity Scholarships in Technological Development and Innovative Extension (CA-DT).

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Published

11/29/2025

Issue

Vol. 12 No. 3 (2025)

Section

Petróleo e Gás Natural

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Copyright (c) 2025 Latin American Journal of Energy Research

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How to Cite

Mendonça Ambrozim, F. (2025) “Comparative analysis of methods for determining total acid number in oil and derivatives from a sustainability perspective”, Latin American Journal of Energy Research, 12(3), pp. 1–9. doi:10.21712/lajer.2025.v12.n3.p1-9.

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