Moringa oleifera (MO) is a multipurpose, medium-or small-sized tree, from regions of northwest India and indigenous to many parts of Asia, Africa, and South America. Its pods have been employed as an inexpensive and effective sorbent for the removal of organics, and coagulant for water treatment. It is a non-toxic natural organic polymer. The main objective of this work was to use the MO seeds as a natural adsorbent for the treatment of dairy industry wastewater (DIW). The effects of agitation time, pH, MO biomass dose, and DIW concentration were evaluated. Removal efficiencies of up to 98%, for both color and turbidity, were reached using 0.2 g MO and 0.2 L of 1.0 g/L sorbate solution (DIW). The obtained results showed that MO seed keeps its adsorption power under a pH range between 5 and 8. The adsorption data was fitted to Langmuir isotherm. There was a significant uptake capacity of MO biomass, q max , which suggested a good affinity between DIW components and sorbent. We conclude that the MO biomass has the potential to be used in the dairy industry wastewater treatment in an efficient way and with low cost.

Polyethersulfone microfiltration membranes (mPES) were modified with polyethilenimine (PEI) and graphene oxide (GO) by layer-by-layer self-assembly method via electrostatic interaction using a pressurized filtration system. The high positively charge of PEI allowed it to be easily assembled on the polyethersulfone substrate, and also to receive the negative layer of GO. Several techniques were applied to characterize the modified membranes (i.e. ATR-FTIR, SEM, water angle contact and zeta potential), and proved that the modification was successfully achieved. The effect of PEI and GO concentrations in the modification was investigated, and the best performance of all membranes was achieved with a Blue Corazol (BC) dye rejection of 97.8% and a pure water permeability of 99.4 L m −2 h −1 bar −1 . The membrane also presented a flux recovery ratio of > 80% after being hydraulically cleaned for 30 min. Moreover, the membrane performance was evaluated in terms of rejection of BC dye in a real dye bath wastewater, and an excellent performance with a maximum rejection rate of 96% was observed. Therefore, the proposed study may provide an efficient alternative to feasible the use of microfiltration membranes, by modifying them, in order to improve its surface characteristics and its filtration capacity, aiming to apply it in the removal of dyes of textile industries wastewater.

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In this article was developed a green synthesis of CuO nanoparticles on vegetal activated carbon (VAC), using pomegranate leaf extract as reducing and stabilizing agent in the removal of multiple pollutants. The impregnated carbons with CuO nanoparticles were characterized morphologically and structurally. The SEM and XRD analysis, after carbons modification, showed that the surface structure remained porous with CuO nanoparticles sizes between 40 and 78 nm. As concern to the contaminants atrazine, caffeine and diclofenac, it is observed that the maximum adsorption capacities practically did not suffer interference by the presence of 1.5% Cu nanoparticles, keeping their values very close to those obtained with pure carbon. The nitrate removal was favored by the impregnation of CuO nanoparticles, from 0.93 mg g-1 to 4.09 mg g-1. The results are promising and demonstrate that it is possible to obtain VAC impregnated whit nanoparticles of CuO by a non-polluting and low cost method.