Assessment of temperature and pressure influence on pH under CO2 saturation conditions and different ions: measurement and modeling applied to gas hydrate kinetics

• Grant number: 17/22589-7
• Support type: Scholarships abroad - Research Internship - Doctorate (Direct)
• Effective date (Start): February 01, 2018
• Effective date (End): October 31, 2018
• Field of knowledge: Engineering - Chemical Engineering
• Principal researcher: Maria Dolores Robustillo Fuentes
• Grantee: Ehsan Heidaryan
• Supervisor abroad: John Paul Martin Trusler
• Home Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: Imperial College London, England
• Associated to the scholarship: 16/09341-3 - Kinetic study on gas hydrate formation and dissociation, BP.DD

Abstract

This project proposes a research plan for an internship in the laboratory of Prof. Dr. J. P.Martin Trusler (London, UK) during 10-month to complement the thesis in progress entitled "Kinetic study of the formation and dissociation of gas hydrates." Hydrate induction time can be significantly affected by various chemical species formed under different suspension pHs values through particle aggregation. The project will build on previous research in which a bespoke apparatus was developed for pH measurements on saline waters at high temperatures and pressure. This has been used to study the pH of CO2-saturated water, and NaCl brines. The literature review indicates that current geochemical models applied to carbon dioxide sequestration from both saline aquifer, by solubility mechanism, and oceanic water, through gas hydrate formation, need further optimization concerning pH prediction, especially over a wide range of temperature. By understanding pH behavior at each experimental temperature and pressure with a determined amount of ion it can be possible to modify the kinetics of hydrate formation or inhibition by changes of the pH of the aqueous phase. In the project, new measurements will be made of the pH of CO2-saturated chloride brines containing different cations including K+, Ca2+, and Mg2+ (low pH systems) as well as anions of hydrate promoters, e.g., SDS, LABSA and SDBS (high pH systems). The new measurements will be coupled with parameter optimization in the Pitzer, ion-interaction model. The range of conditions will extend from low temperatures, relevant to work on clathrate hydrates, to high temperatures pertinent to understanding geological carbon storage in saline aquifers. The findings could improve our basic understanding of hydrate formation during the oceanic storage as well as geological sequestration of carbon dioxide and can be applied to the evaluation of enhancement of sequestration options. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

HEIDARYAN, EHSAN; ROBUSTILLO FUENTES, MARIA DOLORES; PESSOA FILHO, PEDRO DE ALCANTARA. Equilibrium of Methane and Carbon Dioxide Hydrates Below the Freezing Point of Water: Literature Review and Modeling. JOURNAL OF LOW TEMPERATURE PHYSICS, v. 194, n. 1-2, p. 27-45, JAN 2019. (14/25740-0, 16/09341-3, 17/22589-7, 14/02140-7)