Molecular soil remediation

Nano-particles for advanced reduction/oxidation

In this field our work concentrate on layered metal hydroxides - where socalled green rusts - greenish or blue metal hydroxides containing both di- and trivalent iron is in focus. Green rusts are very appealing due to their high reactivity in particular for reduction processes. Thus green rusts have potential for remediation of contaminants such as nitrate, halogenated aliphatic compounds (e.g. chlorinated solvents), nitro aromatic compounds, and selenate. We are modifying green rusts to make metal hydroxide - organo hybride materials to make them strong sorbents as well as strong reductants. For instance, when introduced to polluted aquifers – they can both sorb and dehalogenate chlorinated solvents. In a recent innovation we delaminated oxidized green rusts in order to produce single sheets of iron oxides. Such materials are of substantial interest as sorbents, electro- and photocatalysts.

Phosphorus retention and recycling

Phosphorus is an essential nutrient, with increasing global consumption, decreasing mineral reserves and the main cause of eutrophication of surface waters. Our research follow two lines: i) synthesis and testing of filter materials which retain phosphorus from agricultural drainage waters and other high-volume waters, and ii) phosphorus mobilization/retention in wetlands. The challenge is to develop a fast, strongly and irreversible binding filter material which is one of the focal points in the project SupremeTech and now in the project NuReDrain. In wetlands - which also has been allocated function as phosphorus traps - we focus on phosphorus retention and release during anoxic conditions including a battery of many geochemical reactions: dissolution, re-adsorption and precipitation processes. In particular the role of vivianite (Fe₃(PO₄)₂ 8 H₂O) is being studied.

Soil washing

Current soil remediation techniques for heavy metals and strongly sorbed organic contaminants suffers from being costly, inefficient and slow. Soil wash is an alternative which involves the extraction of contaminants from the soil solid phases by a washing solution with reactive agents such as acids, bases and chelatants. Together with the Analytical Chemistry research group we study environmentally safe soil washing agents potential for remediation of soil. We found biosurfactants to be promising for simultaneous remediation of heavy metals and PAHs, a mixed contamination type commonly found in city and industrial soils.