Methods for determining metal ion leaching from glass cullet using Flame Atomic Absorption Spectroscopy

Abstract

Glass cullet (recycled or broken glass) has been proposed to replace dredged sediment in beach and river recovery processes after severe weather events. Dredging of the ocean floor to replace lost sediment on beaches has led to many negative environmental impacts, such as disturbance of marine ecosystems, notably the death of both animal and plant life near coastlines. The majority of cullet that has been proposed for replacement of dredged sediment is float glass, not bottle glass that could be obtained from a recycling center. This research project focused on developing an efficient method of quantitatively measuring leaching of metal ions from recycled bottle glass cullet, which is the main concern with long-term use of these materials.  A standard concentration of brine was used to incubate the glass cullet, with sample aliquots removed at different exposure times. Flame Atomic Absorption Spectroscopy (FAAS) was used to determine the concentration of metal ions leached out of green cullet from multiple samples. An average concentration of 23.43 ppm of chromium ions was detected after green glass cullet was exposed to 3.5 wt% NaCl solution for five weeks.