Research progress in cleaning and efficient remediation of heavy, toxic, lead-contaminated soil

With the rapid development of industrialization and human civilization, the soil polluted by heavy, toxic lead is becoming increasingly severe worldwide. Thus, it is imperative to control soil pollution due to lead. In this paper, the background, status, and harm of lead-polluted soil were introduced, and the source, mode of occurrence, and extraction of lead from the soil were depicted in detail. Based on the current soil remediation technology, three major methods, namely, physical, chemical, and bioremediation, have been systematically reviewed, and their advantages and disadvantages from the aspects of efficiency, applicability, and economy were evaluated and compared. Results reveal that the most preferred remediation method for heavy, toxic, lead-contaminated soil is chemical remediation. The chemical leaching and immobilization/stabilization methods were subsequently introduced in detail, and the remediation mechanism, effect, applicability, and application prospect of the different types of eluants and curing agents were evaluated and discussed. Finally, the prospect of cleaning and efficient remediation of heavy, toxic, lead-contaminated soil was presented. The restoration should minimize the damage to the soil. For the heavy, lead-contaminated soil, the development of the joint remediation technology is the potential development direction. The mechanism of soil remediation and directional remediation should be determined as soon as possible. Meanwhile, the research and development of multifunctional composite materials should be strengthened.