Removal of Pollutants by Ferrihydrite Nanoparticles Combined with Brij L4 Self-Assembled Nanostructures

Abstract

Release of contaminants such as pharmaceuticals, dyes, pesticides, and industrial wastes due to anthropogenic activities is a threat to human health and the environment. Self-assembled nanostructures of nonionic surfactants are highly efficient in removing organic and inorganic pollutants from various environmental media. Here, we present an evaluation of the pollutant-removal efficiency of Brij L4 nonionic surfactant as a function of the surfactant concentration and self-assembled structures. In addition, small-angle X-ray scattering (SAXS) and rheology were employed to investigate interactions between the Brij L4 isotropic micellar phase and lyotropic liquid crystals and ferrihydrite nanoparticles (Fh NPs). Ferrihydrite nanoparticles in the micellar phase destabilized lyotropic liquid crystals at low surfactant concentrations, while remaining stable in lyotropic phases at high concentrations. Maximum pollutant-removal efficiency (22%) was obtained using a self-assembled nanostructure of pure Brij L4 at 1 wt %. However, Fh NPs are nanoporous and strongly interact with negatively charged organic matter, enhancing the pollutant-removal efficiency of 10 wt % Brij L4. We constructed binary and pseudo-binary phase diagrams at 25 °C of the surfactant in water and in the presence of ferrihydrite nanoparticles, respectively. The Brij L4/water binary phase diagram identified rod-shaped structures at 10 wt % of surfactant. The results of this study identify effective strategies for formulating highly efficient pollutant-removal systems using nanotechnology.

Use of Zero-Valent Iron Nanoparticles (nZVIs) from Environmentally Friendly Synthesis for the Removal of Dyes from Water—A Review

“…Nanotechnology continues to gain momentum as a powerful tool in addressing environmental challenges, establishing itself as one of the most significant applications in different fields, such as water depuration [44], gas cleaning [45], green synthesis [46], catalysis [43], etc. This can be attributed to the profound understanding of nanoparticle properties, enabling the development of novel synthesis methods, and enhancing environmental applications [47].…”

“…By precisely controlling synthesis conditions and appropriate functionalization, it is possible to obtain a narrow range of sizes and shapes. Thus, the properties of nanomaterials can be tailored to some extent [44]. Consequently, nowadays there exists methodologies and technology to tune the dimension and shape of the material, and therefore, its properties, enabling the design of materials with specific characteristics [37].…”

Stability of Viscoelastic Solutions: BrijL4 and Sodium Cholate Mixtures with Metal Ions Across a Broad pH and Temperature Range

“…However, in the EHAC/ C 18 E 18 and EHAC/d-C 12 E 20 solutions, wormlike micelles with shorter contour lengths are formed compared to the pure EHAC solution. 34 Brij L4 is a surfactant that finds increasingly wide application in various areas, for example, as a carrier of biologically active substances such as microorganisms, 35,36 for removal of pollutants, 37 coupling reactions, 38 and obtaining multilayer vesicle-like structures. 39 On the other hand, sodium cholate is a salt form of bile acid, an ionic surfactant used in pharmacy, cosmetology, biotechnology, and chemistry to reduce surface tension and emulsify.…”

Effects of shear-induced crystallization on the complex viscosity of lamellar-structured concentrated surfactant solutions

“…28–30 Veronico et al recently reported a phase diagram for the nonionic surfactant Brij L4 (10–90 wt%)–water binary system at 25 °C. 31…”

“…[28][29][30] Veronico et al recently reported a phase diagram for the nonionic surfactant Brij L4 (10-90 wt%)-water binary system at 25 1C. 31 Caicedo-Casso et al used steady-state rheometry and ultrasonic velocimetry at 22 1C to investigate the rheological behavior of aqueous sodium lauryl ether sulfate (SLES) solutions as a function of surfactant concentration (20-70 wt%). 23 At the highest concentration, the presence of significant flow instabilities such as wall slip, shear banding, and plug flow was detected.…”