South African Journal of Chemical Engineering (Jul 2023)
Comprehensive review of progress made in soil electrokinetic research during 1993–2020, part II. No.1: Materials additives for enhancing the intensification process during 2017–2020
Abstract
This review is a follow-up to our previous review titled “comprehensive review of progress made in soil electrokinetic research during 1993–2020, Part I: process design modifications with brief summaries of main output”. In this review, we have summarized the material additives that are utilized for the enhancement of soil electrokinetic remediation (SEKR) efficiency within the last four years (2017–2020). This review has been divided into six subjects according to determined SEKR categories including removal of inorganic contaminants, removal of organic contaminants, SEKR enhancement using permeable reactive barrier (PRB), SEKR for solidification and soil improvement, SEKR enhancement using an oxidation process, and SEKR enhancement using bioremediation and phytoremediation. Various enhancement materials have been added to improve the primary endeavors of SEKR and the summaries of the output were included in this review. In the SEKR experiments in which inorganic and organic contaminants were removed, the process was evaluated based on the process driving mechanism, particularly electromigration and electro-osmosis. Once the performance of SEKR was inefficient, the SEKR processing was integrated with PRB, oxidation, and bioremediation for significant improvements in SEKR performance. Therefore, the primary aim of our review is to provide a comparison of material additives for the SEKR removal intensification process from 2017 to 2020 to provide a review of the past materials that improved the SEKR performances and to simplify future innovation. During 2017–2020, SEKR studies focused on inorganic and organic contaminants remediation, whereas, few SEKR studies have focused on solidification and soil improvement. The SEKR has been utilized for dewatering, but in this case, the materials added were limited. The insufficient of relevant information on this subject was our primary motivation to write this review.
