Abstract
The tracer diffusion coefficients, D12, of solutes in supercritical carbon dioxide (SC-CO2), modified or not with cosolvents, are necessary for industrial and research applications. In this study, the determination and analysis of D12 values of chromium(III) acetylacetonate in SC-CO2 are presented. The measurements were carried out by the chromatographic impulse response (CIR) method from 308.15 to 333.15K at pressures from 125 to 250bar, and yield diffusivities between 0.570ÿ104 and 1.529ÿ104cm2s1 The experimental trends of D12 with temperature, pressure, density, and Stokes-Einstein coordinates are also presented. Eleven equations were evaluated for modeling the new data, and the best results were achieved using the semi-empirical correlations of Magalhães et al. (error of 1.95% and 1.90%), the universal model of Lito et al. (2.01%), and the predictive modified StokesEinstein equation (3.16%) and Vaz et al. expression (3.27%). Finally, a comparison between the diffusivities of this work and those reported in the literature for other metal acetylacetonates (Co(acac)3, Cr(acac)3, Pd(acac)2 and Pt(acac)2) was accomplished, being possible to conclude that the correct interpretation of the diffusive phenomenon of these systems requires not only the molecular weight but also solute diameter.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.