Design of Experiment for the Optimization of Pesticide Removal from Wastewater by Photo-Electrochemical Oxidation with TiO2 Nanotubes

Abstract

The Design of Experiment (DoE) technique has been used to investigate the photo-electrochemical removal of diuron (DRN) from wastewater. The process is carried out in a photo-electrochemical flow reactor, in which titania nanotubular electrode is irradiated with a simulated solar light. Different operative conditions have been investigated, in a planned 23 full factorial design in which imposed current density, flow rate and initial concentration have been varied at two levels. The removal process of DRN was investigated in terms of specific removal rate (K) and cell voltage (E), which were assumed as objective functions: the results show that the applied current has a paramount effect on both of the objective functions. From the analyses of the intermediates, it appears that the investigated parameters may exert different effects on the distribution of the reaction products: the initial concentration of diuron and the electrode potential seem to play a more important role, in this case.

Effect of Potential and Chlorides on Photoelectrochemical Removal of Diethyl Phthalate from Water

“…In the photoelectrocatalytic process, the increases of the applied potential can accelerate the photogenerated electrons toward the external circuit, generating the bending of the conduction and valence bands, with the consequent formation of a space charge layer. Thus, the recombination of the e − /h + pairs may be decreased or totally prevented, improving the photocatalytic performance [14,15]. Moreover, increase in the potential can empty the defects where the photogenerated charges are trapped, enhancing the photoactivity [16].…”

Experimental design for combined abatement of organic compounds present in urine

“…It was possible to observe that when electrochemical methods are combined with ultrasound and UV, the extent of organic removal is increased. The purpose of the initial factorial design ( 23 ) was to estimate the influence of each factor studied on the degradation of the organic matter present in the urine (TOC, urea, and creatinine), using electrochemical, photochemical, sonochemical methods, and their combinations, without running the risk of exclusion of any factor or interactions that may be important [28]. The variables were evaluated for their significance for the monitored response at 40 min and 14.10 mL min −1 flow rate.…”

“…Electrochemical technology and the combination of electrochemical and photochemical methods (photoassisted electrochemistry) and the combination of electrochemical and ultrasonic processes (sonoelectrochemistry) currently offer promising approaches for preventing pollution problems caused by organic contaminants [15, 18, 20, 27]. For example, a number of systems have been treated, such as cosmetics [18], antibiotics [20], pesticides [28], antineoplastics [15], and dairy industry waste [21].…”

Enhanced Photocatalytic Efficiency of Soft Chemically Synthesized MAl2O4 / Activated Carbon Based Composite in the Removal of Toxic Malachite Green Dye Under Visible Light

“…Many bene ts of this method over other techniques are: (1) full mineralization, (2) no waste-solids removal crisis, and (3) only gentle temperature and pressure situation are necessary [Konstantinou et al 2004]. Metal oxides are extensively used as photocatalysts in removing organic e uents from wastewater because of its stability, high oxidizing ability, harmless phenomena, affordable price, and biocompatibility [Vacca et al 2020]. Spinel aluminates (MAl 2 O 4 ) attract more studies now-a-days because of their exceptional thermal stability, hydrophobicity and low surface acidity [Deraz and Fouda MMG 2013].…”