Solvent effects on higher alcohols synthesis under supercritical conditions: a thermodynamic consideration

The effects of several additional solvents on the equilibrium alcohol yield in the higher alcohols synthesis based on syngas under supercritical conditions were calculated by using the Soave–Redlich–Kwong equation of state. The results showed that the addition of proper solvents could improve the alcohol yield greatly under supercritical conditions. The selection of solvent depends on the size of intent alcohol molecule and the reaction temperature and pressure. While n-hexane or n-heptane is able to improve the methanol synthesis at the temperature of 200−210 °C and the pressure above 8 MPa, higher alkanes such as n-decane or n-dodecane are suitable for the higher alcohols synthesis at higher temperatures (300–380 °C).