Electrohydraulic Fragmentation of Aluminum and Polymer Fractions from Waste Pharmaceutical Blisters

Recently, awareness has been raisedconcerning the need to decrease the total environmental footprint throughoutthe life cycle of a medicine, including the packaging materials. Aluminum, a highlyenergy-intensive metal, is widely used in blister packages together withpolymers. However, these blister packages suffer from poor recyclability, withthe clear majority of waste blister packages (WBPs) disposed of in municipalsolid waste, therefore often being incinerated. In the current study, theseparation of aluminum from the polymer in WPBs was investigated to make Alavailable for direct recycling at a secondary Al facility. The characterizationof WPBs (ICP-OES, SEM-EDS, and TGA) showed that the investigated fractionsconsisted of approximately 10–12 wt % of aluminum, with the clear majority ofwaste blister mass in the polymer fractions, which consisted of two overlappinglayers. Moreover, the polymer layer also gave indications of the presence ofCl. WPBs were subjected to electrohydraulic fragmentation, where the effects ofthe gap between electrodes (10–40 mm), the amount of pulses (50–500 pulses),pulse frequency (2–5 Hz), and discharge voltage (100–180 kV) on the separationprocess were systematically investigated. It was shown that at optimalconditions (electrode gap of 40 mm, 300 pulses, frequency of 3 Hz, 130 kV ofdischarge voltage, and 40 g of initial WPB mass), up to 88% of Al (≥99.4%purity) and polymers were recovered from the investigated waste blistersamples. The current study contributes toward improving the circular economy ofaluminum as well as the reduction in energy consumption by a new application ofelectrohydraulic fragmentation for pharmaceutical blister packages.