Environ Sci Pollut Res Int
April 2024
Lipases represent versatile biocatalysts extensively employed in transesterification reactions for ester production. Ethyl oleate holds significance in biodiesel production, serving as a sustainable alternative to petroleum-derived diesel. In this study, our goal was to prospect lipase and assess its efficacy as a biocatalyst for ethyl oleate synthesis.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
March 2023
Oils and grease (O&G) have low affinity for water and represent a class of pollutants present in the dairy industry. Enzyme-mediated bioremediation using biocatalysts, such as lipases, has shown promising potential in biotechnology, as they are versatile catalysts with high enantioselectivity and regioselectivity and easy availability, being considered a clean technology (white biotechnology). Specially in the treatment of effluents from dairy industries, these enzymes are of particular importance as they specifically hydrolyze O&G.
View Article and Find Full Text PDFTreatment 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.
View Article and Find Full Text PDFMotivated by the search for healthy alimentation and sustainable technological processes, this study aimed to produce a synbiotic composed of the prebiotic galacto-oligosaccharides (GOS) and the probiotic yeast Saccharomyces boulardii, simultaneously, using cheese whey permeate as substrate by enzymatic-fermentative method. A central composite rotatable design with center point was used to evaluate the influence of temperature and enzyme concentration in the GOS and S. boulardii production.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
February 2021
In this study, a biocoagulant synthesized from the association of iron oxide (FeO) 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.
View Article and Find Full Text PDFA distributed parameter model and two lumped parameter models were used in order to find the rate-limiting step in the adsorption process of a herbicide (Diuron) by husks, a possible low-cost adsorbent. For that, four kinetics assays, differentiated by the initial Diuron concentration, were performed. Langmuir isotherm well represented the equilibrium data and through this evaluation, Moringa husks proved to be a potential adsorbent for Diuron removal from water.
View Article and Find Full Text PDFSci Total Environ
April 2020
The objective of this study was to investigate the color removal in a binary mixture of azo dyes from the photovoltaic electrocoagulation (EC) technique, using spectral deconvolution and the Gaussian fit for qualitative and quantitative determination of the physical color parameter. Initially, a conventional energy source was used to feed the EC reactor and the experimental design was conducted according to the Rotational Central Compound Design (RCCD). The spectral deconvolution method associated to the Gaussian fit aided in the description of the composition of the sample matrix, In the first step, through the Analysis of Variance, the RCCD and the three-dimensional surface response graphs, the optimized operating conditions were identified, which corresponded to 1320 A m with an reaction time of 16.
View Article and Find Full Text PDFThe present study proposes the synthesis and characterization of graphene oxide (GO) and its application in the adsorption of the antibiotic cephalexin (CFX) in aqueous solution. The characterization of graphene oxide was obtained by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and zeta potential. The influence of pH on the batch adsorption process was investigated by analysing adsorption equilibrium isotherms and adsorption kinetics.
View Article and Find Full Text PDFSci Total Environ
May 2019
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 TiO-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.
View Article and Find Full Text PDFThe herbicide removal of Diuron in a fixed-bed column packed with the bark biosorbent was investigated experimentally and through phenomenological mathematical modelling. To understand the physical phenomena involved, the steps of external mass transfer resistance, internal mass transfer resistance and the adsorption phenomenon itself were considered as possible limiting steps in the herbicide mass transfer from the liquid to the solid phase. In the developing process of the internal mass transfer resistance model, two hypotheses were considered: constant mass transfer coefficient and mass transfer coefficient as a function of the herbicide concentration in the biosorbent.
View Article and Find Full Text PDFIn this work, the coagulation/flocculation/sedimentation treatment of dairy wastewater samples was investigated through serial factorial designs utilizing the saline extract obtained from (Moringa) as a coagulant. The sedimentation time (ST), pH, Moringa coagulant (MC) dose and concentration of CaCl 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.
View Article and Find Full Text PDFEnviron Technol
August 2017
Continuous flow experiments (450 mL min) were performed in household filter in order to investigate the removal and/or inactivation of T4 bacteriophage, using granular activated carbon (GAC) modified with silver and/or copper oxide nanoparticles at different concentrations. GAC and modified GAC were characterized by X-ray diffractometry, specific surface area, pore size and volume, pore average diameter, scanning electron microscopy, transmission electron microscopy, zeta potential and atomic absorption spectroscopy. The antiviral activity of the produced porous media was evaluated by passing suspensions of T4 bacteriophage (∼10 UFP/mL) through filters.
View Article and Find Full Text PDFThe textile industry is known for the high use of chemicals, such as dyes, and large volumes of effluent that contaminate waters, a fact that has encouraged research and improved treatment techniques. In this study, we used unprocessed soybean hulls for the removal of reactive blue BF-5G dye. The point of zero charge of soybean hulls was 6.
View Article and Find Full Text PDFIn 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.
View Article and Find Full Text PDFA copper (II) ions biosorption by Sargassum sp. biomass was studied in a fixed bed column at 30 degrees C and pH 3.5.
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