Application of Aquatic Plants for the Treatment of Selenium-Rich Mining Wastewater and Production of Renewable Fuels and Petrochemicals

Abstract

Aquatic plants aggressively colonising wetlands are widely used for the biosorption of the soluble contaminants from wastewater and represent an attractive feedstock for biofuel production. Three common Australian aquatic plants, duckweed (Landoltia punctata), elodea, (Elodea canadensis) and water clover (Marsilea quadrifolia), colonizing different depths of wetlands were tested for their ability to treat the selenium-rich mining wastewater and for their potential for production of petrochemicals. The results showed that these plants could be effective at biofiltra- tion of selenium and heavy metals from mining wastewater accumulating them in their fast grow- ing biomass. Along with production of bio-gas and bio-solid components, pyrolysis of these plants produced a range of liquid petrochemicals including straight-chain C14-C20 alkanes, which can be directly used as a diesel fuel supplement or as a glycerine-free component of biodiesel.