Effect of Operating Conditions on （操作条件的影响）.pdfVIP

Effect of Operating Conditions on Static/Dynamic Extraction of Peanut Oil Using Supercritical Carbon Dioxide MEGAN MATRICARDI, ROBERT HESKETH, and STEPHANIE FARRELL CHEMICAL ENGINEERING DEPARTMENT ROWAN UNIVERSITY GLASSBORO, NJ 08012 ABSTRACT Supercritical fluid extraction was successfully used to extract peanut oil from peanuts at temperatures between 40 and 80 °C and pressures of 5000-7000 psi. Static/dynamic cycling was used with a 10 minute static soak time, followed by a 10 minute dynamic interval. The overall extraction time was held constant at 3 hours. Peanut oil yield was determined gravimetrically. The crossover phenomenon was observed with the crossover pressure occurring at 6000 psi. Above the crossover pressure, an isobaric increase in temperature has a positive effect on the extraction yield, while below the crossover pressure an increase in temperature resulted in a decrease in oil yield. Yields between static/dynamic cycling and continuous runs were comparable, suggesting CO2 usage could be reduced by half by static/dynamic cycling, creating a cost effective, greener process. INTRODUCTION Supercritical fluid extraction has emerged as an attractive separation technique for the food and pharmaceutical industries due to a growing demand for “natural” processes that do not introduce any residual organic chemicals. Supercritical CO2 is by far the most commonly used supercritical fluid. The unique solvent properties of supercritical CO2 have made it a desirable compound for separating antioxidants, pigments, flavors, fragrances, fatty acids, and essential oils from plant and animal materials. In the supercr