New Approach for Recycling Office Waste Paper: An Efficient and Recyclable Material for Oily Wastewater Treatment

Recycling has attracted great attention in academia, because of the economic and environmental benefits to industry. An eco-friendly strategy for recycling office waste paper (WP) was used to sustainedly separate oil-water mixtures. The hydroxyl groups of cellulose endow WP with superlipophilic and superhydrophilic properties in air and superoleophobic features under water. WP could separate various oils from oil-water mixtures, with separation efficiencies exceeding 99%. Importantly, the superhydrophilic WP could separate oil-water mixtures containing HCl, NaOH, and NaCl with separation efficiency above 98.9% for at least 30 cycles. The superoleophobicity of WP was maintained in solutions of different pH values for at least 24 h, suggesting good durability and stability. This green method is renewable, clean, cost-effective, and environmentally friendly. More importantly, the recycled office waste paper not only removes oil from oily wastewater (such as in oil spills) but also realizes the recycling of WP. This method could provide new insights into resource recycling.