Synthesis of nanosized amorphous and nanocrystalline TiO₂ for photochemical oxidation of methomyl insecticide in aqueous media

Abstract

Aqueous solution loaded with methomyl insecticide is photocatalytically treated upon UV radiation and TiO 2 in a green sustainable oxidation technique. TiO 2 is a highly promising photocatalytic oxidation method, whereas the main findings is increasing the surface area for maximizing the treatment efficiency. Herein, TiO 2 was synthesized via sonochemical hydrolysis technique and amorphous TiO 2 (TM100) was obtained. Further, annealing of amorphous TiO 2 at 500 ºC resulting in anatase phase TiO 2 (TN500). The phase structure of the both samples was confirmed by high-resolution transmission electron microscope (HR-TEM). The results revealed that the materials exhibited high methomyl removal efficiency due to its nanostructure nature. The optimum TM100 and TN500 for the treatment were 40 and 20 mg/L and resulted in 99.5 and 100% methomyl removal, respectively. Furthermore, pH and H 2 O 2 effect were studied. Additionally, high correlation was attained between empirical and modelled values with a secondorder kinetic model for the two processes.

Development and Characterization of Conjugated Polyaniline/Co-doped ZnO Nanocomposites for Enhanced Dye Oxidation from Wastewater

“…The results in Fig. (8) demonstrated that the reaction rate under UV illumination was increased with decreasing the initial dye load and the percentage dye removals are 98.9, 29.6, 8.6 % for the initial dye concentrations of 5, 10 and 15 ppm, respectively. This phenomenon of increasing the MB dye removal rate with the initial dye concentration can be related to the increase in the dye color of the polluted water, which may cause a shadowing effect that prevents the UV illumination from penetration the aqueous solution.…”

“…The load of the initial MB dye concentration in the aqueous stream on its PANI photo-catalytic oxidation (20 mg/L Pure PANI and 147 mL/min of circulation flow rate) was illustrated in Fig. (8). The results in Fig.…”

“…Photocatalytic oxidation is based on the formation of high reactive groups, namely Numerous catalysts have been introduced as a source of catalytic oxidants, e.g. ZnO [6], TiO 2 [7,8] and iron oxides [9,10]. Such materials are subjected as photocatalyst for wastewater oxidation and completely mineralizing organic pollutants.…”

Synthesis, characterization and potential application of magnetized nanoparticles for photocatalysis of Levafix CA reactive azo‐dye in aqueous effluent

“…Modern societies are associated with clean water scarcity due to industrial wastewater release into the aquatic systems that is polluting watercourse as well as the groundwater (Kositzi et al, 2004; Tony et al, 2019; Tony & Mansour, 2020b). Additionally, water demand is becoming a serious problem that should be solved for sustainable societal needs (Zhang et al, 2019).…”

“…AOPs are including UV‐based process such as UV/Ozone (Andreozzi et al, 2000), UV/H 2 O 2 (Coelho et al, 2006), UV/Fe 2+ or H 2 O 2 /UV/Fe 2+ (Ashour & Tony, 2020) or may be TiO 2 based systems (Kositzi et al, 2004). Fenton's reagent among AOPs is an effective tool for generating high hydroxyl radicals, OH • , yields (Oller et al, 2011) for a complete mineralization of the toxic contaminants ˙OH with no need for a further treatment (Tony, 2020; Valdez et al, 2012) with a harmless end products, CO 2 and H 2 O (Bauer & Fallmann, 1997; Tony & Mansour, 2019; Tony & Mansour, 2020b). Numerous studies used such reagent for treating various types of effluents, that is, dyes (Papić et al, 2009) (El‐Desoky et al, 2010), polymers in wastewater (Tony & Lin, 2021) paracetamol (Velichkova et al, 2013), phenolic compounds (Babuponnusami & Muthukumar, 2012), antibiotics (Pirsaheb et al, 2019) and p‐chlorophenol (Bao et al, 2019).…”