Emulsion templated porous funnel from polypropylene waste for efficient oil separation and spillage management

A huge surge in waste polypropylene (PP) generation, seen after the outburst of coronavirus, has created additional challenges for plastic waste management, which has been a difficult issue to deal with for the past few decades. A novel approach to create a value-added product out of waste PP from face mask and sack is reported here in which an emulsion templated, sacrificial 3D printed porous funnel was developed for efficient oil-water separation. A hitherto unexplored water-in-oil emulsion of PP was formulated for this purpose which was used as a template to create the porous samples. Emulsion templated porous samples showed mesoporous morphology and a specific surface area of more than 170 m2/g, as confirmed by BET and SAXS analysis. A high oil adsorption capacity of 7.5 g/g of the porous sample was observed for petrol which was found to be comparable with a commercial nonwoven PP absorbent pad (8.8 g/g). A 3D printed funnel was fabricated via sacrificial templating, and it was used for the separation of oil (petrol) from contaminated water. The separation efficiency of 99.8% for petrol/water mixture was obtained without any decline in performance, hydrophobicity, and structural integrity of the funnel for ten cycles of use. The approach used in this research can further be extended at a scaled-up level to attain commercial viability of the process and may additionally be used for plastic waste other than PP.