Influence of bionanoparticles to treat a slaughterhouse wastewater.

Treatment of effluents from animal slaughterhouse industries is indispensable, standing out coagulation/flocculation/sedimentation processes. Bionanoparticles (BioNPs) (nanoparticles (NPs) functionalized with Moringa extracts (MO)) were studied as an alternative natural coagulant that would contribute to the microbial load reduction, without increasing the treated effluent toxicity. MO extracts were prepared with different salts, and then, in a kinetics study, different NPs mass and coagulant dosages were evaluated. In the best-defined conditions, microbial load, toxicity tests for the bioindicator Lactuca sativa, and NPs reuse evaluation were performed. Removals of 96.14% turbidity and 43.63% UV254nm were achieved when using 500 mg L-1 of BioNPs containing 60 mg of NPs for every 20 mL of MO extract prepared with 0.1 M CaCl2. The BioNPs with an external magnetic field also decreased the sedimentation time from 140 to 10 min compared to MO, and the process efficiency did not expressively decrease after reusing the recovered NPs. Through toxicity tests, BioNPs were not considered to leave residuals toxic to the Lactuca sativa in the treated effluent. Besides, the microbial load reduction was 97.33% for heterotrophic microorganisms and total mesophiles and 99.25% for moulds/yeasts. Therefore, a satisfactory primary treatment was achieved, contributing to the sustainability of industries.

Synthesis and performance evaluation of a magnetic biocoagulant in the removal of reactive black 5 dye in aqueous medium.

In this study, a biocoagulant synthesized from the association of iron oxide (Fe3O4) nanoparticles and Moringa oleifera Lam (MO) extract was tested in different concentrations for the removal of the apparent colour and dye concentration (reactive black 5) of synthetic textile wastewater. Coagulation/flocculation process was performed and followed by magnetic sedimentation in Jar-Test equipment, the operational parameters studied were sedimentation time and biocoagulant dosage. The efficiency of the C/F/S process was determined by analysing the apparent colour and RB5 concentration, and removals of 93.7% apparent colour and 96.2% RB5 concentration were observed after 20 min of magnetic sedimentation. Reuse tests were performed, which indicated that the biocoagulant and the resulting sludge from the process could be used again for synthesis and used for three consecutive cycles without drastically reducing efficiency (69% for colour removal and 70% for dye concentration). All analyses were conducted considering 95% confidence level. Thus, the proposed biocoagulant demonstrated high potential for the removal of the evaluated parameters in the treatment of textile wastewater due to its high efficiency, simple and fast preparation, and its environmentally friendly qualities.

Functionalized magnetite nanoparticles with Moringa oleifera with potent antibacterial action in wastewater.

Contaminations by Staphylococcus aureus in food industry environments have been extended to industrial Effluent Treatment Plant (ETP). The methodologies used in ETP for bacterial removals and quality parameters adjustment commonly use products toxic to the environment, being mostly inefficient against virulent bacteria such as S. aureus. Seeds of Moringa oleifera Lam. (MO) have potential to be used in ETP as an alternative to harmful products, as it has both the ability to regulate the physicochemical parameters of water and has antibacterial action. Functionalization of MO with magnetite magnetic nano particles (Fe3O4) at nano scale focusing on coagulation and flocculation of wastewater has been gaining prominence. Therefore, the present study evaluated the potential use of the magnetic coagulant MO-Fe3O4 in the elimination of S. aureus in synthetic dairy effluent; concomitantly sought to adjust the quality levels of physicochemical parameters. MO-Fe3O4 added to synthetic dairy effluent at different concentrations amounted to 16 treatments, which were evaluated for removal of color, turbidity, UV254nm and S. aureus on the effluent surface and sludge after 30 min of sedimentation. The results confirmed the efficient elimination of S. aureus simultaneously with a significant reduction of the physicochemical values, with constant efficiency up to 30 min. Scanning electron microscopy images confirm the removal of S. aureus on the effluent surface and sludge. Thus, this study was able to present a natural coagulant capable of remove bacteria and adjust the quality levels of the effluent after 10 min of sedimentation, making this biotechnological innovation highly applicable to ETP.

Evaluation of a magnetic coagulant based on Fe3O4 nanoparticles and Moringa oleifera extract on tartrazine removal: coagulation-adsorption and kinetics studies.

The lack of data regarding the mechanisms at work in the coagulation processes of different substances using magnetic coagulants makes it difficult to understand the phenomena involved and, consequently, makes it difficult to elucidate the mechanisms involved in the coagulation process. Thus, the present study aimed at evaluating the performance of a magnetic coagulant composed of iron oxide (Fe3O4) functionalised with Moringa oleifera (MO) salt extract in the treatment of a synthetic food industry wastewater simulated by the addition of dye to distilled water. From the data obtained in the coagulation/flocculation assays followed by magnetic sedimentation, the different mechanisms involved were evaluated for their fit to pseudo-first order, pseudo-second order, Langmuir and Freundlich theoretical models. The adjustments to the models were evaluated from the kinetic data and indicated that at pH 3 the best fit was to the pseudo-second order model, whereas for pH 6 and 9 the best fit was for the pseudo-first order model. The isothermal data were adjusted to the Langmuir model, suggesting adsorption of a monolayer, characterising chemical processes with selective adsorption. In relation to the mechanisms involved in the process, it is suggested that the neutralisation of charges was the predominant mechanism in the removal of tartrazine at pH 3, whereas at the other pH values evaluated the mechanism that prevailed was monolayer adsorption. Thus, the proposed magnetic coagulant was found to be an efficient alternative material for tartrazine removal, allowing easy separation in the sedimentation stage while also being compatible with environmental issues.

Hybrid treatment of coagulation/flocculation process followed by ultrafiltration in TIO2-modified membranes to improve the removal of reactive black 5 dye.

Many efforts have been made to minimize the polluting effect of wastewater containing dyes that are potentially toxic to the environment. The association of the coagulation/flocculation (CF) process, using saline extract of Moringa oleifera Lam (MO) seeds and subsequently ultrafiltration (UF) in TiO2-modified membranes was performed to remove reactive black 5 dye (10 ppm, RB5) from aqueous solution. The efficiency of the hybrid process was measured by the removal of the dye concentration, apparent color and fouling parameters. The membranes were successfully modified as supported by characterization methods of SEM, FTIR-ATR and WCA. The efficiency of the processes, when applied separately was low. However, after CF and subsequently the filtration in a TiO2-modified membrane both parameters assessed (dye concentration, apparent color) reached 100% of the removal rate. The modified membranes substantially improved permeate fluxes, for instance, after CF the dye flux for modified membrane enhanced around 49% compared with the flux in the pristine membrane. According to these results, the combination of methods was able to effectively remove RB5 dye, in addition to improving permeate fluxes and keeping fouling at low levels.

Potential of the Moringa oleifera saline extract for the treatment of dairy wastewater: application of the response surface methodology.

In this work, the coagulation/flocculation/sedimentation treatment of dairy wastewater samples was investigated through serial factorial designs utilizing the saline extract obtained from Moringa oleifera (Moringa) as a coagulant. The sedimentation time (ST), pH, Moringa coagulant (MC) dose and concentration of CaCl2 have been evaluated through the response surface methodology in order to obtain the ideal turbidity removal (TR) conditions. The empirical quadratic model, in conjunction with the desirability function, demonstrated that it is possible to obtain TRs of 98.35% using a coagulant dose, concentration of CaCl2 and pH of 280 mg L-1, 0.8 mol L-1 and 9, respectively. The saline extract from Moringa presented its best efficiency at an alkaline pH, which influenced the reduction of the ST to a value of 25 min. It was verified that the increase in the solubility of the proteins in the Moringa stimulated the reduction of the coagulant content in the reaction medium, and it is related to the use of calcium chloride as an extracting agent of these proteins. The MC proved to be an excellent alternative for the dairy wastewater treatment, compared to the traditional coagulants.