Study of the Effect of Saline Solution on the Extraction of the Moringa oleifera Seed’s Active Component for Water Treatment

Abstract

Several coagulants/flocculants have been studied in order to remove the color and turbidity of raw water, employing natural ones demonstrated advantages in relation to chemicals. Moringa oleifera Lam is a natural polymer that has been gaining prominence in water treatment. It acts as a clarifying agent, providing a cationic protein that destabilizes the particles contained in a liquid medium. The main objective of the present work is to study the efficiency in terms of removing color and turbidity of raw water in order to obtain drinking water. For this purpose, different coagulant solutions were obtained utilizing three solutions of KCl in different concentrations (0.01, 0.1, and 1 M) and pure water combined with M. oleifera Lam seed. Each coagulant solution obtained was studied with concentrations ranging from 50 to 600 ppm of Moringa in solution. The pH was varied (4.0, 6.0, and 8.0) with 25% and 50% sodium hydroxide solution (NaOH) and hydrochloric acid (HCl), respectively. The tests were conducted with the "Jar Test Device" and the efficiency of the process was evaluated regarding the reduction of color and turbidity. The best results were found employing the coagulant solutions extracted with 1 M salt solution, pH 8.0, and different concentrations of coagulant solution. It is important to explain that the best results were in various concentration ranges, as the concentration of protein in solution becomes higher, the greater is its power as a coagulant. The lowest content of protein was found in the solution extracted with water, which consequently had the lowest values of color and turbidity removal.

Application of Hybrid Process of Coagulation/Flocculation and Membrane Filtration to Water Treatment

“…The differences may be due to the different preparation procedures of the moringa solution, by aqueous or saline extraction, as well as the different concentrations of the stock solution of moringa. In both studies, the coagulant properties of the moringa appear to be more efficient in water of high initial turbidity, in agreement with other literature reports (Ndabigengesere et al, 1995;Madrona et al, 2010). Ndabigengesere et al (1995), applying an aqueous solution of 5% moringa seeds to synthetic turbid water (kaolin added to tap water) with initial turbidity of 426 NTU, obtained removals from 80 to 90% and reached the optimum concentration of 500 mg/L of coagulant solution.…”

“…Madrona et al (2010) evaluated the extraction of the coagulant protein in the presence of potassium chloride (KCl) at different concentrations. The authors have shown that greatest coagulation efficiencies are achieved with KCl 1 mol/L, reaching nearly 100% removal of color and turbidity from water with initial turbidity of 850 NTU.…”

“…To prepare the 1% stock solution of moringa (concentration of 10,000 mg/L), 1 g of peeled seeds was crushed and added to 100 mL of distilled water. Subsequently, the solution was stirred for 30 min and vacuum filtered (Cardoso et al, 2008;Madrona et al, 2010). From the 1% stock solution, moringa solutions were prepared with different concentrations: 25,50,75,100,125,150,175,200,225,250,275, and 300 mg/L.…”

Guluronic acid content as a factor affecting turbidity removal potential of alginate

“…Additionally, natural or synthetic polymeric substances are used as coagulants alone or as coagulant aids together with metal salts. A number of natural materials have coagulating abilities such as chitosan, starch and alginate (Ahmad et al 2006;Devrimci et al 2012;Divakaran and Pillai 2002;Guibal and Roussy 2007;Labille et al 2005;Madrona et al 2010;Qudsieh et al 2008;Sand et al 2010;Tripathy and Singh 2001). Natural polymers are advantageous because they are less toxic and more biodegradable (Bolto and Gregory 2007).…”

Processamento de sementes de Moringa oleifera utilizando-se diferentes equipamentos para obtenção de solução coagulante

“…Há procedimentos manuais nos quais se utiliza pilão para trituração das sementes (Okuda et al, 1999;Okuda et al, 2001) podendo ocorrer, após trituração, peneiramento do pó obtido para retirada de partículas maiores (Paterniani et al, 2009;Paterniani et al, 2010). Outros autores adotam a metodologia com obtenção do pó utilizando liquidificador doméstico ou (Ndabigengesere et al, 1995;Katayon et al, 2006) e até mesmo preparo da solução diretamente no liquidificador (Madrona et al, 2010).…”