Abstract
Wastewater produced during the petroleum extraction process and the release of large volumes of hydrocarbon-contaminated wastewater by petrochemical industries are of major concern because of their potential impacts on the environments, animals, plants, and humans. Both the crude emulsions and hydrocarbon-contaminated wastewater contain an enormous amount of suspended solids, oil, and grease, organic matter, highly toxic elements, high salts, and recalcitrant chemicals. The treatment of crude oil emulsion has been one of the most important challenges due to the complex nature and generation of a substantial amount of waste to meet the increasing demand for oil and its derivatives. Engineered hybrid and assembly nano- and micro-scale materials have appealed the attention of scientists and researchers because of their elegant functional structures with unique properties and promising applications in the fields of sensing, magnetic, optical, catalysis, and demulsification. Magnetic hybrid materials exhibit some interesting properties of magnets-induced separation along with recycling properties, which may favor their widespread practical uses. The modification and coating of magnetic nanoparticles with different materials having special wettability properties will not simply isolate them from external environments but also contributes to the sustainable separation of oil-water mixtures. This review elaborates on the recent research advancement on the design, fabrication, and wettability properties of hybrid magnetic materials fabricated from polymer and inorganic nanoparticles, and their potential applications in separating oil-water mixtures. After a brief introduction to the design and fabrication of nanoscale hybrid functional magnetic materials, their properties including wettability, morphology, and self-assembly are discussed. We also highlight the current research scenarios of magnetic hybrid and assembly materials along with a key role in environmental and demulsification/separation applications. Finally, the prospects of magnetic materials, ongoing challenges, and opportunities in this arena are also directed.
•Oil-water emulsions, stability and physicochemical aspects are reviewed.•Fabrication of magnetic hybrid materials with special wettability properties is discussed.•The persistence of petroleum-originated pollutants causes threats to the living ecosystems.•Application of magnetic hybrid material for the effective separation of oil-water emulsion is presented.