Assessment of the Equivalence of Methods for the Determination of the Vapor Pressure of Oil and Oil Products

   Current regulatory documents in Russia establish the need for testing laboratories to determine such parameters as saturated vapor pressure using the Reid method, air saturated vapor pressure, total vapor pressure of crude oil. In analytical practice, appropriate reference materials are used for measurement quality control, method validation, metrological traceability establishment, and other purposes. In addition, the calculation of various vapor pressure equivalents using correlation equations (DVPE – dry vapor pressure equivalent, RVPE – Reid vapor pressure equivalent, etc.) is regulated by appropriate methods for determining vapor pressure. Vapor pressure is a method-dependent parameter; so many producers of reference materials use interlaboratory experiment as a way to establish a certified value. Thus, when conducting an interlaboratory experiment in the process of certification of reference materials, it was revealed that laboratories can incorrectly interpret the obtained experimental data – consider values of the air saturated vapor pressure, total vapor pressure and even calculated vapor pressure equivalents as the Reid vapor pressure. To solve this problem, the authors of this work set the goal of assessing the equivalence of methods for determining the vapor pressure of oil and oil products used in testing laboratories in order to identify the key characteristics of the stated methods and assess their equivalence. The article discusses methods the vapor pressure determination using an automatic vacuum chamber and a Reid bomb. Various matrices of reference materials (hydrocarbons, gasoline, commercial oil, gas condensate) were investigated, and the calculated vapor pressure equivalents were obtained and compared. It was shown that the air saturated vapor pressure, dry vapor pressure equivalent, Reid vapor pressure equivalent, and total vapor pressure cannot be equated to the saturated vapor pressure values determined by the Reid method. A comparative assessment of methods for determining the vapor pressure of oil and oil products used in testing laboratories can be of assistance to developers of regulatory documents for oil, gas condensate, and motor gasoline, revealing the need to separate the requirements for vapor pressure parameters of the considered objects of analysis and providing empirical material.

1. Safonov А. S., Ushakov A. I., Chechkenev I. V. Automotive fuels: Himmotology. Operational properties. Saint Petersburg: NPIKC; 2002. 264 p. (In Russ.).

2. Podvintsev I. B. Oil refining: Practical introductory course. 2^th ed. Dolgoprudnyi: Intellekt; 2015. 160 p. (In Russ.).

3. Rybak B. M. Analysis of petroleum crude and products. 5th ed. Moscow: Gostoptekhizdat; 2002. 888 p. (In Russ.).

4. Nascimento M. H. C., Oliveira B. P., Rainha K. P., Castro E. V. R., Silva S. R. C., Filgueiras P. R. Determination of flash point and Reid vapor pressure in petroleum from HTGC and DHA associated with chemometrics. Fuel. 2018;234:643–649. doi: 10.1016/j.fuel.2018.07.050

5. Issa H. M., Albarzanji A. A. Quantitative prediction of Reid vapor pressure for a light crude oil using a simplified and proper correlation. Petroleum Science and Technology. 2020;38:745–753. doi: 10.1080/10916466.2020.1776731

6. Landera A., Mac N., George A. Development of robust models for the prediction of Reid vapor pressure (RVP) in fuel blends and their application to oxygenated biofuels using the SAFT-γ approach. Fuel. 2021;283. doi: 10.1016/j.fuel.2020.118624

7. Mendes G., Aleme H. G., Barbeira P. J. S. Reid vapor pressure prediction of automotive gasoline using distillation curves and multivariate calibration. Fuel. 2017;187:167–172. doi: 10.1016/j.fuel.2016.09.046

8. Gaspar D. J., Phillips S. D., Polikarpov E., Albrecht K. O. Measuring and predicting the vapor pressure of gasoline containing oxygenates. Fuel. 2019;243:630–644. doi: 10.1016/j.fuel.2019.01.137

9. ASTM D323–20a Standard test method for vapor pressure of petroleum products (Reid Method). doi: 10.1520/D0323–20A (Accessed: 15. 07. 2023).

10. ASTM D5191–20 Standard Test Method for Vapor Pressure of Petroleum Products and Liquid Fuels (Mini Method). doi: 10.1520/D5191–20 (Accessed: 15. 07. 2023).

11. ASTM D6377–20 Standard Test Method for Determination of Vapor Pressure of Crude Oil: VPCRx (Expansion Method). doi: 10.1520/D6377–20 (Accessed: 15. 07. 2023).

12. ГОСТ 10227–86 Топлива для реактивных двигателей. Технические условия = Jetfuels. Specifications. М.: Стандартинформ, 2005.

13. ГОСТ 1756–2000 Нефтепродукты. Определение давления насыщенных паров = Petroleum products. Determination of saturated vapours pressure. М.: Стандартинформ, 2005.

14. ГОСТ 2084–77 Бензины автомобильные. Технические условия = Motor petrols. Specifications. М.: ИПК Издательство стандартов, 2003.

15. ГОСТ 2177–99 Нефтепродукты. Методы определения фракционного состава. Метод Б = Petroleum products. Methods for determination of distillation characteristics. Method B. М.: ФГБУ РСТ, 2021.

16. ГОСТ 2517–2012 Нефть и нефтепродукты. Методы отбора проб = Petroleum and petroleum products. Methods of sampling. М.: Стандартинформ, 2018.

17. ГОСТ 28781–90 Нефть и нефтепродукты. Метод определения давления насыщенных паров на аппарате с механическим диспергированием = Petroleum and petroleum products. Method for determination of saturated vapours pressure by mechanical dispersing. М.: Издательство стандартов, 1991.

18. ГОСТ 31874–2012 Нефть сырая и нефтепродукты. Определение давления насыщенных паров методом Рейда = Crude oil and petroleum products. Determination of vapour pressure by Reid method. М.: Стандартинформ, 2013.

19. ГОСТ 32513–2013 Топлива моторные. Бензин неэтилированный. Технические условия = Automotive fuels. Unleaded petrol. Specifications. М.: Стандартинформ, 2019.

20. ГОСТ 33157–2014 Нефтепродукты. Метод определения давления насыщенных паров (мини-метод) = Petroleum products. Test method for vapor pressure of petroleum products (mini method). М.: Стандартинформ, 2019.

21. ГОСТ 33361–2022 Нефть. Определение давления паров методом расширения = Crude oil. Determination of vapor pressure by expansion method. М.: ФГБУ РСТ, 2022.

22. ГОСТ 8.532-2002 Стандартные образцы состава веществ и материалов межлабораторная метрологическая аттестация. Содержание и порядок проведения работ = State system for ensuring the uniformity of measurements. Certified reference materials of composition of substances and materials. Interlaboratory metrological certification. Content and order of works. М.: Стандартинформ, 2008.

23. ГОСТ 8.601-2010 Давление насыщенных паров нефти и нефтепродуктов. Методика измерений = State system for ensuring the uniformity of measurements. Saturated vapours pressure of petroleum and petroleum products. Measurement procedure. М.: Стандартинформ, 2019.

24. ГОСТ EN13016-1-2013 Нефтепродукты жидкие. Часть 1. Определение давления насыщенных паров, содержащих воздух (ASVP), и расчет эквивалентного давления сухих паров (DVPE) = Liquid petroleum products. Part 1. Determination of air saturated vapour pressure (ASVP) and calculated dry vapour pressure equivalent (DVPE). М.: Стандартинформ, 2019.

25. ГОСТ Р 51858–2002 Нефть. Общие технические условия = Crude petroleum. General specifications. М.: Стандартинформ, 2020.

26. ГОСТ Р 51866–2002 (ЕН 228–2004) Топлива моторные. Бензин неэтилированный. Технические условия = Automotive fuels. Unleaded petrol. Specifications. М.: Стандартинформ, 2009.

27. ГОСТ Р 52340–2005 Нефть. Определение давления паров методом расширения = Crude oil. Determination of vapour pressure with expansion method. М.: Стандартинформ, 2005.

28. ГОСТ Р ЕН 13016-1-2008 Нефтепродукты жидкие. Часть 1. Определение давления насыщенных паров, содержащих воздух (ASVP) = Liquid petroleum products. Part 1. Determination of air saturated vapour pressure (ASVP). М.: Стандартинформ, 2008.

29. ГСО 11065–2018 Стандартный образец свойств газового конденсата (СО ГК-ПА-1) // Федеральный информационный фонд по обеспечению единства измерений : официальный сайт. URL: https://germeon.ru/catalog/item/73400/ (Дата обращения: 15. 07. 2023).

30. ГСО 11381–2019 Стандартный образец состава и свойств нефти (СО СС-ТН-ПА-2) // Федеральный информационный фонд по обеспечению единства измерений : официальный сайт. URL: https://petroanalytica.ru/%D0%B3%D1%81%D0%BE-%D0%BD%D0%B5%D1%84%D1%82%D0%B8/%D0%B3%D1%81%D0%BE-%D1%81%D0%BE%D1%81%D1%82%D0%B0%D0%B2%D0%B0-%D0%B8-%D1%81%D0%B2%D0%BE%D0%B9%D1%81%D1%82%D0%B2-%D0%BD%D0%B5%D1%84%D1%82%D0%B8-2 (Дата обращения: 15. 07. 2023).

31. ГСО 9817–2011 Стандартный образец давления насыщенных паров нефтепродуктов (СО ДНП-ПА) // Федеральный информационный фонд по обеспечению единства измерений : официальный сайт. URL: http://granat-e.ru/gso_dnp-pa_asvp.html (Дата обращения: 15. 07. 2023).