Phase Equilibrium and Density of CO2 + Acetic Acid Systems from 308.15 to 338.15 K and 15 to 45 MPa

Teng Zhu; Yuming Li; Houjian Gong; Mingzhe Dong

doi:10.1021/acsomega.0c05462

Phase Equilibrium and Density of CO₂ + Acetic Acid Systems from 308.15 to 338.15 K and 15 to 45 MPa

ACS Omega. 2021 Mar 5;6(10):6663-6673. doi: 10.1021/acsomega.0c05462. eCollection 2021 Mar 16.

Authors

Teng Zhu¹, Yuming Li², Houjian Gong³, Mingzhe Dong⁴

Affiliations

¹ State Key Laboratory of Heavy Oil Processing, College of Science, China University of Petroleum, Beijing 102249, PR China.
² State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, PR China.
³ School of Petroleum Engineering, China University of Petroleum (East China), Qingdao, Shandong 266580, PR China.
⁴ Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta, Canada T2N 1N4.

Abstract

Using a high-pressure phase equilibrium apparatus and vibrating-tube densimeter, phase transition pressures of CO₂ (1) + acetic acid (2) binary systems with x ₂ = 0.000, 0.107, 0.163, 0.222, and 1.000 were measured under temperatures from 308.15 to 338.15 K. Besides, the densities at the same composition and temperature under pressure from 15 to 45 MPa were also detected, and the volumes of mixing (ΔV _m) were calculated. Three prediction models (SRK EOS, PC-SAFT EOS, and TS model) were introduced to predict and correlate the density of binary systems, which was found to have positive relationships with temperature and acetic acid concentration and a negative relationship with pressure. Thereinto, the variation trend of CO₂ density with pressure tends to be flat under high pressure, and which of acetic acid density increased linearly with pressure. ΔV _m are negative, and their absolute value increases with the increase of temperature and the decrease of pressure. The work herein could provide a theoretical guide and basic data for supercritical CO₂ extraction technology and CO₂ application in oil field development.