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In this work, to evaluate the effectiveness of the coagulation/flocculation using a natural coagulant, using Moringa oleifera Lam functionalized with magnetic iron oxide nanoparticles, producing flakes that are attracted by an external magnetic field, thereby allowing a fast settling and separation of the clarified liquid, is proposed. The removal efficiency of the parameters, apparent color, turbidity, and compounds with UV254nm absorption, was evaluated. The magnetic functionalized M. oleifera Lam coagulant could effectively remove 90 % of turbidity, 85 % of apparent color, and 50 % for the compounds with absorption at UV254nm, in surface waters under the influence of an external magnetic field within 30 min. It was found that the coagulation/flocculation treatment using magnetic functionalized M. oleifera Lam coagulant was able to reduce the values of the physico-chemical parameters evaluated with reduced settling time.

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In this study, the proposed adsorbent composed of graphene oxide (GO) functionalized by magnetic nanoparticles of iron oxide (α-γ-FeO) was obtained by a simple ultrasonication process. This new material was used for the removal of glyphosate in water. The nanoparticulated iron oxide used was synthesized by means of a modified sol-gel method, which does not use organic solvents. The adsorbent material (GO-α-γ-FeO) obtained was characterized by magnetic measurements, and it can be proved that it has superparamagnetic properties, allowing fast and efficient magnetic separation. The equilibrium time for the adsorption of glyphosate when using GO-α-γ-FeO was 2 hours and the maximum removal was 92% at 15°C, with a maximum adsorption capacity of 46.8 mg g. Langmuir model and pseudo-second-order kinetic model correlated satisfactorily to the experimental data. The thermodynamic parameters showed that the adsorption of glyphosate on GO-α-γ-FeO was spontaneous, exothermic and thermodynamically favorable at temperature of 15-45°C. Thus the adsorbent material GO-α-γ-FeO proposed in this study is considered a good candidate to be used in the removal of glyphosate from aqueous solutions, presenting high adsorption capacity, low cost and magnetic properties that facilitate the separation of the adsorbent material.

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.

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