Intensification of textile effluent chemical oxygen demand reduction by innovative hybrid methods

Treatment of Pharmaceutical Effluent by Sono‐Fenton‐Sorption

“…In addition, acoustic streaming caused due to ultrasound waves improved the mass transfer . Further, the reduction in sorbent size was observed due to ultrasound irradiation and this may be due to the breakage of solid particles. This breakage has two benefits on degradation: decreasing particle size enhances surface area, which is very much required for a better sorption; and breakage increases the number of solid particles present.…”

“…The results showed k obs as less (9 Â 10 À4 min À1 ; R 2 ¼ 0.90) compared to sonolysis. On the other hand, when the process was conducted at effluent's natural pH (5), the COD reduction observed was 9.38%. The decrement in COD reduction is due to the fact that, above pH 3, ferrous sulfate precipitates as Fe(OH) 3 [9] and Fe(OH) 2 .…”

“…Although AOPs were efficient, complete mineralization requires large amount of energy and this in turn increases the operating cost of the process. To overcome this drawback, different AOPs were combined to obtain synergistic effects . Ghauch et al studied the destruction of carbamazepine by combined Fenton's process and low‐frequency ultrasonication.…”

Textiles

“…An overall numerical correlation using regression analysis for decolorization time with operating conditions of the ozonation process was presented. The study by Nachiappan and Muthukumar (2010) showed the results of the reduction of textile effluent COD by sonolysis, sorption, sono-sorption and sono-Fenton methods. A tea waste activated using sodium hydroxide, folmaldehyde, ultrasound irradiation (US), formaldehyde followed by US, and sodium hydroxide followed by US was used as an adsorbent.…”

Degradation Reactive Black 5 dye from aqueous solutions using ozonation with pumices and pumices modified by nanoscale zero valent iron (nZVI)

“…Advanced oxidation processes (AOPs) are alternative methods for the elimination of types of refractory compounds, principally due to the formation of hydroxyl radicals (HO•). During advanced oxidation processes (AOPs), additional reactions occur in the presence of light that produce hydroxyl radicals or increase the production rate of hydroxyl radicals that are capable of rapidly oxidizing organic contaminants and converting them into harmless end-products, such as H 2 O and CO 2 , and inorganic ions from atoms, which have been successfully used for the treatment of wastewaters from petrochemical, textile, and pharmaceutical industries (Dimoglo et al, 2004;Tekin et al, 2006;Chakinala et al, 2009;Nachiappan and Muthukumar, 2010;Oller et al, 2011;Farzadkia et al, 2014;Wang et al, 2014;Gholami et al, 2016). Previous studies have documented the removal/degradation of benzotriazole with advanced techniques in recent years (e.g., ferrate (VI) oxidation, ultrasonic, adsorption,…”