Magnetic coagulant based on Moringa oleifera seeds extract and super paramagnetic nanoparticles: optimization of operational conditions and reuse evaluation

Abstract

a b s t r a c tThe aim of this study was the development of a new magnetic coagulant based on nano structured iron oxide functionalized by Moringa oleifera (MO) compounds present in aqueous saline extract, for water treatment, with removal of the physical-chemical indicatives parameters, turbidity, apparent color, and compounds with absorption at UV 254nm (UV 254nm ). The nano structured iron oxide(maghemite, γ-Fe 2 O 3 ) was synthesized without organic solvents use. These nanoparticles were functionalized by the compounds present in aqueous saline MO (without oil, extracted by ethanol and hexane) extract. Tests of coagulation and flocculation were performed by using a Jar Test equipment with medium to high turbidity water (80 NTU). The magnetic coagulant achieved removals of 94.4% for turbidity, 87.5% for apparent color and 63.4% for UV 254nm , with surface waters using applied magnetic field within 30 min of settling. The treatment of coagulation followed by flocculation with magnetic functionalized MO coagulant could lessen physico-chemical properties assessed with diminished sedimentation time. The coagulant used in the study can be reused without significant loss of efficiency due to possibility of magnetic separation, showing an economically viable method and low environmental impact.

Protein fractionation of Moringa oleifera Lam. seeds and functionalization with magnetic particles for the treatment of reactive black 5 solution

“…It was observed that the FTIR spectra of the iron oxide nanoparticles presented two bands at 1608 and 1384 cm −1 , corresponding to residual nitrate and carbonate from the synthesis process; a further two bands between 700 and 551 cm −1 were attributed to Fe‐O bonds . Figure also shows the FTIR spectrum of the sludge resulting from coagulation, after being washed with ethanol for reuse.…”

“…Santos et al also evaluated the reuse capacity of magnetic nanoparticles washed with ethanol for functionalization of the moringa extract and performed a characterization after washing. The authors observed that, after washing with ethanol, the nanoparticles did not present bands from residual impurities of the synthesis, such as nitrate and carbonate (1400–1700 cm −1 ) and C‐H groups (2900–2800 cm −1 ).…”

Adsorbed leucaena protein on citrate modified Fe3O4 nanoparticles: synthesis, characterization, and its application as magnetic coagulant

“…There were some researchers that combined iron oxide nanoparticles and natural coagulant to improve the coagulation performance, especially in terms of settling time [4][5][6][7][8][9][10]. There are two approaches that have been used, firstly the protein as active coagulating agent was used to functionalize the surface of iron oxide nanoparticles, secondly, the iron oxide nanoparticles were dispersed in crude extract of natural coagulant.…”

“…Different types of iron oxide nanoparticles, α-Fe 2 O 3 , γ-Fe 2 O 3 , and Fe 3 O 4 , have been studied by Santos group to remove turbidity and color from synthetic wastewater [5][6][7][8][9]. In those researches, iron oxide nanoparticles were dispersed in crude extract of M. oleifera, where it was found that significant removal of turbidity and color was achieved within short settling time (less than 30 min) under magnetic settling.…”

Adsorbed leucaena protein on citrate modified Fe3O4 nanoparticles: synthesis, characterization, and its application as magnetic coagulant

“…Different types of iron oxide nanoparticles, α-Fe 2 O 3 , γ-Fe 2 O 3 , and Fe 3 O 4 , have been studied by Santos group to remove turbidity and color from synthetic wastewater [5][6][7][8][9]. In those researches, iron oxide nanoparticles were dispersed in crude extract of M. oleifera, where it was found that signi cant removal of turbidity and color was achieved within short settling time (less than 30 min) under magnetic settling.…”