Mask Waste: A Sustainable Mask-Based Epoxy Resin/SiO₂ Composite for Efficient Purification of Water-in-Oil Emulsions

Since the emergence of the COVID-19 pandemic, there has been a tremendous increase in the production of masks worldwide, with more than 1.5 billion masks having been disposed of during this time. The damage caused by mask pollution is a global threat; highlighting the need to dispose of discarded masks correctly. Herein, we report a recycling approach that uses discarded masks to fabricate a superhydrophobic epoxy resin/SiO2 membrane for separating emulsions. The composite has a high flux value (2123 L·m–2·h–1) and high separation efficiency (>98%). The filter maintained its excellent superhydrophobic property (WCA > 150°) after tape-peel cycles, clamping cycles with tweezers, abrasion cycles with 800 grit SiC sandpaper, pressure with fingertips, and kneading cycles. This study proposes a renewable, eco-friendly, and low-cost product, which can be used for oil spill cleanup and water purification. The filter not only removes oil from oily wastewater (such as oil spills) but also solves pollution caused by discarded masks. This study provides insights for resource recovery that may contribute to the purification of oily water emulsions.