Solubility of n-alkanes in supercritical CO2 at diverse temperature and pressure. Issue 9 (March 2015)

• Record Type: Journal Article
• Authors: Shi, Qingzhao; Jing, Lishuai; Qiao, Weihong
• Is Part Of: Journal of CO₂ utilization. Issue 9(2015)Supplement
• Page Start: 29
• Page End: 38
• Publication Date: 2015-03
• Subjects: scCO2 -- Solubility -- n-Alkane -- Cloud point pressure; Carbon dioxide -- Periodicals; Carbon dioxide -- Environmental aspects -- Periodicals; Carbon dioxide mitigation -- Periodicals; Carbon dioxide; Carbon dioxide -- Environmental aspects; Carbon dioxide mitigation; Periodicals; 628.53205
• DOI: 10.1016/j.jcou.2014.12.002
• Languages: English
• ISSNs: 2212-9820

Abstract

Graphical abstract: Highlights: We measured solubility of n -alkanes in CO2 . Temperature and alkane chain length will increase cloud point pressure. x Rises with pressure, temperature increase will reduce x . The solubility of n -alkanes has direct access to density of CO2 . Abstract: Poor solubility of heavy hydrocarbons in CO2 has limited the application of CO2 -EOR (enhanced oil recovery) in modern oil recovery industry to some extent. Therefore, it is crucial to investigate the solubility regularity of different hydrocarbons in supercritical carbon dioxide (scCO2 ) in the first place. In this paper, our objective is to explore the solubility of n -alkanes (C6 H14 –C18 H38 ) in scCO2 . To measure cloud point pressures, the experiment utilizes high-pressure view chamber, and results for accuracy and repeatability of the experimental method and instrument are evidently positive. Then, cloud point pressures for n -alkanes from 318 K to 343 K show a proximately linear and positive correlation with the temperature; they also increase with expanding chain length of n -alkanes. In addition, the result of x (molar fraction of n -alkane at cloud point pressure) indicates that x has a positive correlation with the pressure at identical temperature, and when pressure is constant, temperature increase will reduce x . Finally, relationship studies between density of CO2 and x reveal that, density of CO2 has a positive influence on the solubility of n -alkane, and the Chrastil model corrects ln ρ and ln S data. The measured data align with the Chrastil model, with a maximum AARD value of 9.85%.