<b>Electro-flocculation associated with the extract of <i>Moringa oleifera</i> Lam as natural coagulant for the removal of reactive blue 5G dye

Abstract

ABSTRACT.Although an important significant sector in world economy, the textile industry is known for its large volumes of wastewater generated in production processes. In the search for cleaner technologies, the application of electrochemical processes, such as electro-flocculation, or natural coagulants, such as Moringa oleifera Lam extract, have become recurrent in literature. Since the required operating conditions for alternative technologies are such that they hamper effective application, current paper presents results obtained with the use of a hybrid system of treatment which combines electroflocculation and the aqueous extract of Moringa oleifera lam to evaluate the removal of reactive blue 5G dye from aqueous solutions. Milder conditions of electric current intensity (0.10 -1.50 A) and natural coagulant concentration (250-2000 mg L -1 ) were tested. Through a Central Composite Rotatable Design, it was possible to obtain a quadratic model which subsidized the optimization of operating conditions. Applying an electric current of 0.97 A to sacrificial electrodes of iron and a concentration of 2000 mg L -1 for the extract of Moringa oleifera Lam, an average 86.79% color removal was obtained, considered a satisfactory rate.

A comprehensive review on Moringa oleifera nanoparticles: importance of polyphenols in nanoparticle synthesis, nanoparticle efficacy and their applications

“…Iron oxide nanoparticles (FeO-NPs), which have a variety of uses including antimicrobial food coatings, catalysis and cosmetics, have received a great deal of attention due to their special qualities and applications [ 74 ]. Several reports stated the successful production of iron or iron oxide NPs using Moringa leaves [ 43 , 75 – 77 ], fruit [ 78 ], seeds extract [ 27 , 43 , 79 ] and its oils [ 80 ].…”

“…The average size determined by Scherrer's equation is corroborated by the average size seen in TEM micrographs (between 10 and 20 nm). The NPs have cubic shape [ 27 ]. Iron oxide nanorods (FeO-NRs) were reported to be produced biochemically from FeCl 3 and M. oleifera .…”

“…In time being, various parts of the plant were broadly used in several environmental, industrial, dietary supplements, and medical applications [ 23 – 25 ]. For instance, seed powder is used in the so-called coagulation-flocculation processes for cleaning drinking water from environmental contaminants such as pesticides, dyes, and pharmaceuticals [ 26 , 27 ]. Also, different parts of the plant, including seeds, flowers, and leaves are good nutritious source of protein, lipids, vitamins, beta-carotene, minerals, and other nutrients, which are being exploited in food technology [ 24 , 28 – 31 ].…”

Modified biochar from Moringa seed powder for the removal of diclofenac from aqueous solution

“…The other parts such as the leaves have been used as sorbent in various water treatment studies (Maina et al 2016). The seed husk has also been Responsible editor: Tito Roberto Cadaval Jr * Afrouz Bagheri bagha@uef.fi studied in the adsorption of diclofenac (Araujo et al 2018), acid black 1 and basic red 2, reactive dyes, heavy metals, atrazine, and nitrobenzene from solution (Buildings et al 1997;Akhtar et al 2007;de Carvalho et al 2015;Matouq et al 2015;Tavengwa et al 2016;Maina et al 2016;Souza et al 2016;Tavares et al 2017;Coldebella et al 2017;Khorsand et al 2017;Maria et al 2018;Shirani et al 2018).…”

Efficiency of the electrochemical treatment of textile effluent using two configurations of sacrificial electrodes

“…After the residual iron supernatant was removed, the absorbance was evaluated in a single beam spectrophotometer Hach DR2800 at a wavelength of 618 nm (SANTOS et al, 2016).…”