Insight on water remediation application using magnetic nanomaterials and biosorbents

Abstract

Adsorption to date is the most effective and utilized technology globally to remove several pollutants in wastewater. In this approach, many adsorbents have been synthesized, tested and used for the elimination and separation of the contaminants such as radionuclides, heavy metals, dyes and pharmaceutical compounds both at lab and industrial scale. However, there are many challenges to adsorption processes such as reducing the high cost, through means of separation of suspending adsorbents to be used again, as well as the ease to synthesize. Two methods that have shown promising results and gained significant interest is that of magnetic nanomaterials and biosorbents due to their effective, safe, eco-friendly, low cost and low-energy intensive material properties. Magnetic nanomaterials act as efficient adsorbents due to their ease of removal of contaminants from wastewater using an applied magnetic field but also their advantageous surface charge and redox activity characteristics. On the other hand, biosorbents have a synergistic effect with their efficient adsorption capacity to remove contaminants, high abundance and participation in waste minimization, helping alleviate ecological and environmental problems. This review highlights, discusses and reports on the state-of-the-art of these two promising routes to adsorption and provides indications as to what are the optimum materials for utilization and insight into their efficiency, reusability and practicality for the removal of pollutants from wastewater streams. Some of the main material focuses are zero-valent iron, iron oxides, spinel ferrites, natural and waste-based biosorbents.

Adsorption of Cr(VI), Ni(II), Fe(II) and Cd(II) ions by KIAgNPs decorated MWCNTs in a batch and fixed bed process

“…These foremost properties enhanced the suitability of nanomaterials application in water treatment, catalysis, medicine and biotechnology 12 . At the moment, nanomaterials-based adsorbents such as zinc oxide, tin oxide, graphene oxide, carbon nanotubes, silica, aluminum oxide, titanium oxide, zeolites, iron oxide, spinel ferrites, chitosan, carbon nanofibers and cerium oxide have been employed by different researchers for industrial wastewater treatment 17 – 25 . Among these nanomaterials, carbon nanotubes (CNTs) have been extensively exploited due to their large surface area, ease of modification, extraordinary surface chemistry, structural control, low density, porosity, higher thermal stability, high chemical stability, regeneration ease and reusability, compared to other adsorbents 26 .…”

Recent Developments in the Application of Nanomaterials in Agroecosystems

“…In the course of their life cycle, these materials can experience numerous transformations and reach a number of ecological compartments. They are anticipated to be seen in waters and sediments of fresh and marine water systems, soil, atmosphere, and biota [15][16][17][18][19].…”

Removal of Agrochemicals from Waters by Adsorption: A Critical Comparison among Humic-Like Substances, Zeolites, Porous Oxides, and Magnetic Nanocomposites

“…Nevertheless, it must be said that, despite the strength of all the above considerations, large-scale field applications of magnetic metal-ceramic nanocomposites in environmental decontamination are not reported in the literature, to the best of our knowledge, as confirmed by [90,91]. Furthermore, these two valuable works evidence that, among the various obstacles that the use of magnetic metal-ceramic nanocomposites in environmental decontamination encounters, the main issues are those regarding their commercialization, which appear, at the moment, to particularly hinder their use in practical application of a wider scale.…”