Solubilities of Anthraquinones in Pressurized Solvents

A.E. ANDREATTA; R.E. MARTINI; M.F. BARRERA VAZQUEZ; S.BOTTINI

Congreso; PROSCIBA; 2016

tIn the field of natural products, anthraquinones are an important category of secondary metabo-lites present in various vegetable species. They are highly bioactive compounds, potentially useful fortherapeutic applications, as antiviral, anti-bacterial and anti-cancer agents. Extraction processes usingpressurized hot water offer an environmentally friendly alternative to traditional extraction and purifica-tion methods applied to anthraquinone-containing plants. Knowledge on high-pressure phase equilibriaof anthraquinone + solvent mixtures is required to evaluate the potentiality of these processes. The needis for both, experimental data and thermodynamic models that are able to predict phase boundaries at dif-ferent process conditions. In this work, the solubility of 1,4-dihydroxy-9,10-anthraquinone (quinizarin)in pressurized hot water has been measured, using a simple and reliable dynamic method. For the binaryquinizarin + H2O, the measurements were performed at (333, 353, 373, 393, 413, 443, 463) K and pres-sures of (30, 60 and 90) bar. The group-contribution with association equation of state (GCA-EOS), withthe definition of a cyclic ketone functional group (CyC O) was used to calculate solid-liquid equilibriaof binary mixtures of anthraquinones with pressurized hot water. This model was able to give a goodrepresentation of the solubility behaviour of quinizarin in water.