Advanced aerogels from waste tire fibers for oil spill-cleaning applications

Abstract

Abstract Petroleum spills have been described as one of the leading aquatic disasters that has resulted in the destruction and degradation of marine ecosystems worldwide, destroying the lives of thousands of organisms within a short period. Parts of the causes of this may be linked to waste products from plastics and rubber tires. This study focuses on fibers from rubber tires, and successfully produces rubber aerogels from them using glutaraldehyde and poly(vinyl alcohol) binders, followed by a freeze-drying process. Our recycled rubber aerogels are extremely pore (92.2–98.3 %) and ultra-low density (0.020−0.091 g/cm3). After a methyltrimethoxysilane (MTMS) coating, rubber aerogels show their super-hydrophobic properties with a water contact angle up to 153°. The effects of rubber fiber and cross-linker contents on the rubber aerogel oil absorption efficiency are thoroughly investigated. Pseudo-first-order and pseudo-second-order kinetics are studied for the absorption of rubber aerogel and the result shows that the pseudo-second-order model could better predict oil absorption performance. A maximum rubber aerogel oil absorption of up to 25.0 g/g is estimated, approximately 1.7 and 2.8 times higher compared to commercial polypropylene mat and nonwoven polypropylene, respectively. Such a material can play an instrumental role towards recycling of car tires and paves the way for maximizing the recycling capacity of waste rubber tires globally. This will in turn reduce the global and environmental impact of waste pollution associated with untreated car tires.