Estudo do processo de extração do óleo da Macaúba (Acrocomia Intumescens

Abstract

The macaúba-barriguda (Acrocomia intumescens) is a palm tree species with common occurrence in the northeastern forest zone. The fruit is widely consumed in natura by the population. Both the pulp and the almond produce oils with unstudied properties. The objective of this study was to analyze the efficiency of macauba's almond and pulp oil extraction process through mechanical pressing and solvent extraction (leaching) with the help of an experimental design. The biometric characterization of the fruits was performed with the aid of a pachymeter and analytical balance. The pulp was extracted with a knife after drying at 60 ° C and the almonds were removed through a mechanical press and dried at the same temperature until reaching the constant mass. In mechanical extraction by the hydraulic press were used these pressures: 330; 412.5; 495 and 577.5 kgf/cm². For the leaching, a complete 23 factorial design was elaborated. Three variables were used: extraction time, solvent and extraction method, in two levels of control: inferior and superior, the time being defined in 3 hours and 6 hours, the solvent In hexane and isopropanol and the method of extracting the oil in standard soxhlet and continuous extraction. The factorial design of the pulp and almond oil extraction showed approximately similar results, being the time of extraction the most significant factor, followed by the solvent and the other interactions. The pressure extraction of 577.5 kgf/cm² showed the highest amount of extracted oil with 24.1 grams of oil in 100 g of pulp and 21.7 grams of oil for the same initial mass of almond. The highest oil yield obtained in the experimental design was higher than 31% on the almond using continuous extraction, with isopropanol as the solvent for 6 hours of extraction, and higher than 38% for the pulp under the same conditions. The extracted oils were characterized according to the humidity, density, pH, and acidity index. The oil almond proved suitable to use for purposes of biodiesel production according to the desired specifications. The exception was the density, which was higher than indicated. The combination of mechanical extraction and solvent extraction at lower pressures proved to be a good option for oil content, presenting higher results than those obtained through mechanical pressure at higher pressures.