Filtration of TNT and heavy metals by using pine bark

Pine bark is a low cost sorbent originating from the forest industry. In recent years, it has been found to show promise as an adsorbent for metals and organic substances in contaminated water. In a new study. an industrial effluent, collected from Nammo Vingåkersverken demilitarization factory, was diluted to form concentration ranges of contaminants and shaken with pine bark for 24 hours. Metals (e.g. Pb, Zn, Cd, As and Ni) and explosives, e.g. 2,4,6-trinitrotoluen, TNT, were analysed in the effluent. The aim of the experiment was twofold; firstly, it was to investigate whether metals are efficiently removed in the presence of explosives and secondly, if adsorption of explosive substances to pine bark was possible. It was found that metal uptake was possible in the presence of TNT and other explosive contaminants. The uptake of TNT was satisfactory with up to 80 % of the TNT adsorbed by pine bark. Further studies are, however, necessary before any recommendation to substitute active carbon for pine bark can be made.