Oil pollution remediation with mass-producible and recyclable amphiphilic magnetic Janus particles

The growing global energy demand and declining conventional oil supply have accelerated the use of unconventional heavy crude oils (UHCOs). However, high viscosities of UHCOs make conventional remediation methods ineffective for removing them from water. To address this challenge, we propose Pickering emulsification using amphiphilic magnetic Janus particles (AMJPs) as an efficient remediation method for UHCOs. AMJPs are produced using a multiplexed 3D-printed microfluidic droplet generator. The design of the generator is carefully optimized through a combination of experimental and numerical studies to achieve mass production of the monodisperse particles. These AMJPs have the remarkable ability to emulsify oil pollutants, with viscosities ranging from as low as 0.31 mPa∙s to as high as 97,100 mPa∙s. The Pickering emulsification using AMJPs results in rapid and highly efficient (>99.7%) recovery of UHCOs from water in a recyclable manner. We realize the first ever mass production of AMJPs via 3D-printed droplet generators. The use of these AMJPs in the Pickering emulsification approach has potential applications beyond UHCO remediation, including food, cosmetics, and pharmaceutical industries.