High-performance wastewater treatment based on reusable functional photo-absorbers

Current scientific advances in wastewater treatment increase our ability to acquire clean water; one of these methods is the use of solar energy. Solar irradiation is an important source of renewable energy; thus, extensive efforts have been devoted to the development of light-absorbing particles that can achieve light-to-heat conversion. In this study, novel solar evaporation systems were designed and developed, with magnetic nanoparticles as photo-absorbers. The magnetic nanoparticles were coated with carriers, such as graphene oxide and paper. These hydrophilic carriers could provide large surface areas, low thermal conduction, or microporous surfaces for steam generation. Magnetic nanomaterials can absorb over 95% of sunlight; thus, an evaporation efficiency of up to 75% at only 1 kW/m(2) irradiation, as well as a decreased volume of wastewater were achieved. Furthermore, a reasonable amount of clean water was collected. These nanomaterials could be separated from wastewater by magnetic force, which can significantly reduce material consumption. These novel strategies successfully overcame previous problems, such as the demand for a high amount of sunlight. This study also opens an opportunity for the construction of a solar evaporation system for wastewater treatment with photo-absorbers. (C) 2016 Elsevier B.V. All rights reserved.