Urban mining: Phytoextraction of noble and rare earth elements from urban soils

Abstract

The increasing demand for noble metals boosts their price. In order to meet the increasing demand for elements, a number of technologies are being developed to recover elements already present in the environment.Traffic-related metal pollution is a serious worldwide concern. Roadside soils are constantly subjected to the deposition of metals released by tailpipe gases, vehicle parts, and road infrastructure components. These metals,especially platinum group elements from catalytic converters, accumulating in the soil pose a risk both for agricultural and residential areas. Phytomining is suggested as a novel technology to obtain platinum group metals from plants grown on the contaminated soil, rock, or on mine wastes. Interest in this method is growing as interest in the recovery of rare metals is also increasing. Based on the research of many authors, the sources and amounts of noble metals that accumulate in soil along communication routes have been presented. The paper presents also plants that can be used for phytomining.

Keywords

• platinum group elements,
• soil,
• environmental pollution,
• phytomining,
• phytoremediation,
• roads