Document Type
Article
Publication Date
1-1-2015
Abstract
By considering the absorbed power and energy based on heating power profile during extraction, a generalized model with washing coefficient (b), diffusion coefficient (k) and predictive parameter namely absorbed power density (APD) was developed for microwave-assisted extraction (MAE) at any operational heating modes. To study the model, MAE of flavonoids from cocoa (Theobroma cacao L.) leaves was conducted using the heating modes (constant-power, two-steps-power, intermittent-power and constant-temperature) at various microwave power (100–300 W) and extraction temperature (50 °C and 70 °C). The results shows that the model (b = 0.5595 and k′ = 0.01279 mL/J) is able to predict the normalized extraction yields of MAE at any heating modes, heating power, microwave system, extraction scale and batch of plant sample with less than 4% discrepancy. The accuracy of the prediction relies on particle size of sample (0.25–0.60 mm), type of extraction solvent (85% aqueous ethanol) and solvent to feed ratio (50 mL/g).
Keywords
Absorbed power density (APD), Absorbed energy density (AED), Generalized model, Heating modes, Normalized extraction yield
Divisions
fac_eng
Publication Title
Separation and Purification Technology
Volume
143
Publisher
Elsevier