Application of natural surfactants for improving the leaching of zinc and copper from different soils

Threats connected with contamination of environment with heavy metals include negative influence on human and animal health and also negatively influence the biodiversity of ecosystems. While applying various techniques of heavy metal remediation from soils, an important problem is the adsorption of ions on solid particles. In this respect, the composition and properties of soil strongly affect the efficiency of the process. Therefore, the aim of this study was to determine the efficiency of copper(II) and zinc(II) ions leaching from soils of different types (luvisols, podzols, chernozem) by means of natural surfactants: Quillaja saponaria extract containing saponins and biosurfactant produced by P. aeruginosa belonging to rhamnolipids. The studies included both heavy metal removal tests from soils and the evaluation of ecotoxicity of applied surfactants towards soil microorganisms. The results obtained allow to conclude that especially the saponins from Q. saponaria constitute an effective and environmentally safe remediation agent, allowing to achieve elimination from luvisols over 80% for zinc(II) ions and 70% for copper(II) ions. [Display omitted] •High effectiveness of natural surfactants for heavy metal removal was confirmed.•The most effective surfactant in remediation was Quillaja saponaria extract.•Chernozem adsorb heavy metals the most strongly among the tested soils.•Zinc(II) ions were relatively more easily removed than copper(II) ions.