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The prime objective of the current investigation is to evaluate a promising alternative method for disinfection wastewater using a novel electro-oxidation unit. The study focused on determining the best-operating conditions from a techno-economic point of view to be applied to continuous flow simulating actual disinfection modules. The treatment unit consisted of a Plexiglas container with a 3 L volume containing nine cylindrical shape electrodes (6 graphite as anode and 3 stainless steel as a cathode) connected to a variable DC power supply. Determination of the best operating parameters was investigated in batch mode on synthetic wastewater by studying the effect of contact time, current density (CD), total dissolved solids concentration (TDS), and bacterial density. Moreover, the continuous mode experiment was considered on real wastewater from an agricultural drain and the secondary wastewater treatment plant effluent before chlorination. The batch mode results revealed that the best applicable operational conditions that achieved the complete removal of E. coli were at a contact time of less than 5 min, TDS of 2000 mg/L, and CD of 4 mA/cm2. Application of these conditions on the continuous mode experiment indicated the complete removal of all bacterial indicators after 5 min in the drainage wastewater and after 3 min in the secondary treated wastewater. Physico-chemical characterization also suggested that no chlorine by-products displaying the hydroxide ion formed due to water electrolysis is the main reason for prohibiting the growth of pathogenic microbes. The electrical consumption was calculated in the continuous mode and found to be 0.5 kWh/m3 with an operational cost of about 0.06 $/m3, including the cost of adding chemicals to increase the TDS. The results proved that this novel electro-oxidation unit is a robust and affordable disinfection method for complete bacterial removal from wastewater and is more environmentally benign than other conventional disinfection methods. [ABSTRACT FROM AUTHOR]

This article investigates the effect of Ni2+ content on structural (XRD, XPS), morphological (TEM), and magnetic behaviors of silica magnesium zirconium copper nanoceramics calcined at 800 °C. The sol–gel route is followed for the silica magnesium zirconium copper/(0.0–0.7) Ni2+ samples preparation. X-ray photoelectron spectroscopy is employed to analyze the chemical states of elements for the samples. The three representative binding energy magnitudes for O, Ni, and Cu reside at 534, 857, and 979 eV, consecutively. The saturation magnetization constricts with the elevation of Ni2+ content, while the magnetic hysteresis loop resembles the superparamagnetic attitude. The optical spectra present the possibility of direct and indirect transitions in the prepared nanoceramics. Energy gap (value and type), refractive index, and real and imaginary dielectric constant were extracted. The energy gap approaches 3.75 eV and 3.71 eV for direct and indirect transitions correspondingly with (0.7) Ni2+. The antimicrobial and the toxicity performance of all inspected nanocomposites were conducted against pathogenic microbes. The attained results evidenced that SMZC-0.7Ni possesses energetic antimicrobial potential against all targeted microbes. The investigated SMZC-0.7Ni nanocomposite functioned to eradicate frequent waterborne pathogens in wastewater at an appropriate dose (100 mg/L), demonstrating that SMZC can be utilized as a competent disinfectant in the municipal wastewater decontamination process. Inherently, SMZC-0.7Ni can be employed as an excellent nano-weapon against multiple dangerous microorganisms. [ABSTRACT FROM AUTHOR]

Herein, we exploited xanthan gum (XG) and cationic dextran (CD) in designing a novel porous aerogel (XCD) loaded with different concentrations of a new bistriazole derivative (CPSC). The CPSC was deposited into and onto the pores of aerogels. The neat aerogel removed both AB40 dye and Cu2+ efficiently. Adding 0.5 g of CPSC to the neat aerogel (XCD-0.50 sample) improved slightly the adsorption of Cu2+ and has no effect on the adsorption of AB40 dye. XCD-0.50 removed almost completely 10 mg/L of AB40 dye in 10 min using 0.5 g/L at pH i 6 while for Cu2+ longer contact time (90 min) and higher dosage (2.0 g/L) were required to remove 10 mg/L solution at pH i 5. Relative to literature, the Langmuir adsorption capacity of XCD-0.5 toward AB40 dye (436 mg/g) was the highest and toward Cu2+ (60 mg/g) was comparable to others. The aerogel XCD-0.50 was regenerable and reusable for three cycles with reasonable efficiency. By submerging a bacterial solution (106 CFU/mL) in the XCD-0.75 aerogel for 90 min, an impressive 6-log decrease in the number of bacteria was obtained under ideal circumstances. Crucially, toxicity test clearly confirmed that the prepared aerogels had non-toxic impact. Across all investigated bacterial species, XCD-0.75 continuously achieved a 6-log CFU decrease after 180 min, demonstrating its efficacy in the context of disinfection experiment. The results of the study highlight the extraordinary potential of the biopolymer aerogel loaded with CPSC as a potent adsorbent and disinfectant. They show significant removal of toxic trace elements and dyes, along with microbial reduction in industrial wastewater, underscoring the aerogel's potential use in water treatment. [ABSTRACT FROM AUTHOR]