The “Lab4treat” Outreach Experience: Preparation of Sustainable Magnetic Nanomaterials for Remediation of Model Wastewater

Abstract

The Lab4treat experience has been developed to demonstrate the use of magnetic materials in environmental applications. It was projected in the frame of the European project Mat4Treat, and it was tested several times in front of different audiences ranging from school students to the general public in training and/or divulgation events. The experience lends itself to discuss several aspects of actuality, physics and chemistry, which can be explained by modulating the discussion depth level, in order to meet the interests of younger or more experienced people and expand their knowledge. The topic is relevant, dealing with the recycling of urban waste and water depollution. The paper is placed within the field of water treatment for contaminant removal; therefore, a rich collection of recent (and less recent) papers dealing with magnetic materials and environmental issues is described in the Introduction section. In addition, the paper contains a detailed description of the experiment and a list of the possible topics which can be developed during the activity. The experimental approach makes the comprehension of scientific phenomena effective, and, from this perspective, the paper can be considered to be an example of interactive teaching.

Insights into performances of magnetic and bio-based doped-nanohydroxyapatites as water decontamination agents

“…Crystal Violet (cationic), instead, was captured, but only by nAp-Fe-BBS powder (Figure 6a), reaching the 60% adsorption level in 1 hour and thus confirming the affinity of this dye with BBS. 16,23,62 Qmax was estimated through isotherm fitting with the Langmuir model (R 2 =0.92) as 52 mg g -1 (see Figure 6b), which is in line with the average results of other hydroxyapatite-based systems and, in general, other materials already described in the literature. [63][64][65][66] In the tested conditions, the CV desorption was limited to 1-2%.…”

“…15 For example, the incorporation of iron into hydroxyapatite structure is of great interest for the possibility of forming nanoparticles with magnetic properties and developing efficient adsorbent materials and catalysts that can be removed by applying a magnetic field. 16,17 The use of organic substances as templates or, in general, modifiers in the synthesis of nanohydroxyapatites can significantly influence the morphology and surface chemistry of the final materials, causing a significant improvement in sorbent capacity. 18,19 These strategies have been exploited by Mercado et al, 20,21 who synthesized paramagnetic ironcontaining hydroxyapatite nanoparticles and paramagnetic materials further added with soluble bioorganic substances (SBOs, in particular, the so-called CVT230) derived from 230 days-composted urban wastes as synthesis precursors.…”

An Overview of Environmental Catalysis Mediated by Hydrogen Peroxide

“…Table 1 shows a selection of recent works reporting iron as the main com or coadjuvant in remediation routes. Indeed, the opportunities of obtaining Fe-con materials from natural sources (entries 10, 23 and 24 in Table 1) or preparing d kinds of iron-based compounds are uncountable [41,47,[50][51][52][53]. Moreover, even in…”

“…Table 1 shows a selection of recent works reporting iron as the main component or coadjuvant in remediation routes. Indeed, the opportunities of obtaining Fe-containing materials from natural sources (entries 10, 23 and 24 in Table 1) or preparing different kinds of iron-based compounds are uncountable [41,47,[50][51][52][53]. Moreover, even in Fenton and photo-Fenton processes defined as "heterogeneous", iron can be added as a homogeneous reactant (entries 13, 15 and 21 in Table 1).…”

“…Regarding the use of magnetic iron-based oxides, they have been presented as a convenient tool not only to perform heterogeneous Fenton-like reactions, but also to allow for a better and easier separation from the water medium [50]. Many works have described these systems; for instance, in Table 1, they are exemplified in entries 6, 7, 9, and 17.…”