Experimental Design Procedure for Optimization of Saponin Extraction from Glycyrrhiza glabra: A Biosurfactant for Emulsification of Heavy Crude Oil

摘要

In petroleum industries, an emulsification process is often necessary to transfer and upgrade heavy crude oil. Saponins are the main group of biosurfactants used for this purpose and they are often extracted from plants. In this study, saponin was extracted from Glycyrrhiza glabra using a soxhlet method. The aim of present study was to optimize the effective parameters in production of saponin in order to obtain the maximum emulsification index (E-24) and optimum mean droplet size by Taguchi method. The evaluated parameters include extraction temperature, first solvent volume fraction, second solvent volume fraction and n-butanol volume fraction. Response parameters resulted in yield, cost and E-24 of produced saponin. The obtained results showed that temperature and n-butanol volume fraction were the most effective factors in the extraction process. Optimum operation condition including yield, cost and E-24 were (3.6 +/- 0.1) g/200 g of plant material, (3.4 +/- 0.14) $/g and (98 +/- 5)%, respectively. The mean droplet size of water in oil (W/O) emulsion was (35 +/- 6) lm using dynamic light scattering (DLS) analysis. The results of present research could reduce the cost of saponin production for the applications in oil industries.