Separation and Purification Process of Natural Materials by Using Supercritical Fluids

Abstract

In this paper, our researches on extraction, separation, and fractionation of natural materials by using supercritical fluids such as carbon dioxide are reviewed. We measured extraction rate as a function of operating conditions for the extraction of oils, essential oils, antioxidants, and the other bioactive compounds from various natural materials. The solubility was measured and estimated for these components. Based on these results, theoretical models were developed and the extraction behavior for natural materials was analyzed and simulated.
For the fraction process of liquid mixture, we have developed countercurrent extractor with supercritical carbon dioxide, where phase behavior near the critical point is effectively utilized. Deterpenation process of citrus oils was established by the experimental and theoretical study for orange, lemon, and bergamot oils. As a new process for continuous fractionation of essential oils, we have developed supercritical pressure swing adsorption process where adsorption/desorption behavior in supercritical carbon dioxide was utilized. The separation processes were successfully applied for the separation of tocopherols.