Measurements and Predication of Infinite Diffusion Coefficients for Z-ligustilide in Supercritical Carbon Dioxide
WANG Guo-Qing, LI Yong-Hui, MO Xu-Fei, Lyu Hui-Sheng , ZHANG Min-Hua
R&D Center of Petrochemical Technology, Key Laboratory for Green Chemical Technology of Ministy of Education, Tianjin University, Tianjin 300072, China
Abstract The infinite diffusion coefficients of Z-ligustilide in supercritical carbon dioxide were measured by Taylor capillary peak broadening method under 10—18 MPa at 305.15—323.15 K. Experimental results showed that the obtained diffusion coefficients were in the range of 2.75×10-8 m2·s-1 to 5.55×10-8 m2·s-1. It increased with increasing temperature and decreased with increasing pressure and supercritical carbon dioxide density. When the temperature and pressure were constant, the diffusion coefficient increased with increasing content of ethanol in supercritical carbon dioxide. Different modified correlation models including Wilke-Chang, Scheibel, Lusis-Ratcliff, Reddy-Doraiswamy, He-Yu-Su were used to predict the infinite diffusion coefficients of Z-ligustilide. The predicted diffusion coefficients agreed well with the experimental results and the average absolute deviation was 9.352%, 9.356%, 9.354%, 9.360%, 10.444% respectively. The above models could play good performance in the prediction of diffusion coefficients in our work.
WANG Guo-Qing, LI Yong-Hui, MO Xu-Fei, LyuHui-Sheng , ZHANG Min-Hua.Measurements and Predication of Infinite Diffusion Coefficients for Z-ligustilide in Supercritical Carbon Dioxide[J] Chemcial Industry and Engineering, 2014,V31(6): 46-52