Soxhlet extraction of solid materials: an outdated technique with a promising innovative future

Abstract

An overview of the evolution of Soxhlet extraction of solid materials and its comparison with the performance of other conventional and new extraction techniques is presented. First, a discussion on both conventional Soxhlet as compared with other conventional extraction techniques and some minor improvements of the former for specific applications is done. Secondly, a critical comparison of conventional Soxhlet with the new extraction techniques such as supercritical fluid extraction, microwave-assisted processes and microwave-assisted solvent extraction shows the reasons why major, recent improvements of this technique (namely Soxtec ® System HT, Soxwave-100 and focused microwave-assisted Soxhlet extraction) have been proposed, aimed at overcoming most of the shortcomings of conventional Soxhlet and converting it into an updated tool for leaching which competes advantageously with the most recent alternatives in the extraction field.