For assessing the effects of wastewater on soil physical and chemical properties, manual irrigation (MI) and surface drip irrigation (SDI) systems were investigated. The experiment was conducted over 12 months. Before and after the experiment, soil samples were collected from three depths (0–20 cm, 20–40 cm and 40–60 cm) for analysis. The obtained results indicated that wastewater application probably preserves soil quality by maintaining its pH-water values whatever the irrigation system used. This study suggested that nutrient input from wastewater promotes soil microbial activity and organic matter (OM) mineralization. In fact, at the soil depths of 0–20 cm and 20–40 cm, MI using treated wastewater (TWW) leads to decrease OM content. P input may justify treated wastewater fertilizing effect in the topsoil. Moreover, TWW fertilizing effect was demonstrated by increased potassium (K) amount in the two upper soil layers (0–20 cm and 20–40 cm) following SDI system. This last system may block metals (iron (Fe), copper (Cu), cobalt (Co) and selenium (Se)) translocation to plants and their accumulation in soil. In contrast, metal translocation was maintained by the MI system. The present data is encouraging to reuse TWW for agricultural purposes, especially for orchard irrigation.

An excessive accumulation of crystal violet dye in the human body results in an accelerated heart rate, tetraplegia, eye irritation, and long-term damage to the transparent mucous membrane that protects the eyeballs. Accordingly, in this paper, sodium manganese silicate/sodium manganese silicate hydroxide hydrate was easily fabricated as a novel type of nanostructures for the successful disposal of crystal violet dye from aqueous solutions. The formed sodium manganese silicate/sodium manganese silicate hydroxide hydrate nanostructures after the hydrothermal treatment of the gel produced from the interaction of Mn(II) ions with Si(IV) ions at 180 °C for 6, 12, 18, and 24 h were abbreviated as MS1, MS2, MS3, and MS4, respectively. The XRD showed that the average crystallite size of the MS1, MS2, MS3, and MS4 samples is 8.38, 7.43, 4.25, and 8.76 nm, respectively. The BET surface area of the MS1, MS2, MS3, and MS4 samples is 41.58, 46.15, 58.25, and 39.69 m²/g, respectively. The MS1, MS2, MS3, and MS4 samples consist of spherical and irregular shapes with average grain sizes of 157.22, 88.06, 43.75, and 107.08 nm, respectively. The best adsorption conditions of the crystal violet dye employing the MS1, MS2, MS3, and MS4 products were achieved at pH = 8, contact time = 140 min, and solution temperature = 298 kelvin. The linear pseudo-2nd-order model as well as the linear Langmuir isotherm better describe the disposal of the crystal violet dye using the MS1, MS2, MS3, and MS4 adsorbents. The studied thermodynamic parameters indicated that the disposal of the crystal violet dye employing the MS1, MS2, MS3, and MS4 adsorbents is spontaneous, exothermic, and chemical. The maximum disposal capacities of the MS1, MS2, MS3, and MS4 adsorbents towards crystal violet dye are 342.47, 362.32, 411.52, and 310.56 mg/g, respectively.

It is essential to remove rhodamine 6G and acid orange 10 dyes from contaminated water because they can induce cancer and irritate the lungs, skin, mucous, membranes, and eyes. Hence, in the current work, the Pechini sol–gel method was used for the facile synthesis of ZrO₂/CdMn₂O₄/CdO as novel nanocomposites at 600 and 800 °C. The synthesized nanocomposites were used as novel adsorbents for the efficient removal of rhodamine 6G and acid orange 10 dyes from aqueous media. The nanocomposites, which were synthesized at 600 and 800 °C, were abbreviated as EK600 and EK800, respectively. The synthesized nanocomposites were characterized by EDS, XRD, N₂ adsorption/desorption analyzer, and FE-SEM. The patterns of XRD showed that the average crystal size of the EK600 and EK800 nanocomposites is 68.25 and 85.32 nm, respectively. Additionally, the images of FE-SEM showed that the surface of the EK600 nanocomposite consists of spherical, polyhedral, and rod shapes with an average grain size of 99.36 nm. Additionally, the surface of the EK800 nanocomposite consists of polyhedral and spherical shapes with an average grain size of 143.23 nm. In addition, the BET surface area of the EK600 and EK800 nanocomposites is 46.33 and 38.49 m²/g, respectively. The optimal conditions to achieve the highest removal of rhodamine 6G and acid orange 10 dyes are pH = 8, contact time = 24 min, and temperature = 298 kelvin. The greatest removal capacity of the EK600 and EK800 adsorbents towards rhodamine 6G dye is 311.53 and 250.63 mg/g, respectively. Additionally, the greatest removal capacity of the EK600 and EK800 adsorbents towards acid orange 10 dye is 335.57 and 270.27 mg/g, respectively. The removal of rhodamine 6G and acid orange 10 dyes using the EK600 and EK800 adsorbents is spontaneous, exothermic, follows the Langmuir adsorption isotherm, and fits well with the pseudo-first-order kinetic model.

Photocatalysis is an efficient and an eco-friendly way to eliminate organic pollutants from wastewater and filtration media. The major dilemma coupled with conventional membrane technology in wastewater remediation is fouling. In this study, the photocatalytic degradation potential of novel thermoplastic polyurethane (TPU) based NiO on aminated graphene oxide (NH₂-GO) nanocomposite membranes was explored. The fabrication of TPU-NiO/NH₂-GO membranes was achieved by the phase inversion method and analyzed for their performances. The membranes were effectively characterized in terms of surface morphology, functional group, and crystalline phase identification, using scanning electron microscopy, Fourier transformed infrared spectroscopy, and X-ray diffraction analysis, respectively. The prepared materials were investigated in terms of photocatalytic degradation potential against selected pollutants. Approximately 94% dye removal efficiency was observed under optimized conditions (i.e., reaction time = 180 min, pH 3–4, photocatalyst dose = 80 mg/100 mL, and oxidant dose = 10 mM). The optimized membranes possessed effective pure water flux and excellent dye rejection (approximately 94%) under 4 bar pressure. The nickel leaching in the treated wastewater sample was determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). The obtained data was kinetically analyzed using first- and second-order reaction kinetic models. A first-order kinetic study was suited for the present study. Besides, the proposed membranes provided excellent photocatalytic ability up to six reusability cycles. The combination of TPU and NH₂-GO provided effective strength to membranes and the immobilization of NiO nanoparticles improved the photocatalytic behavior.

The effluents of industrial wastewater contain several toxic organic and inorganic pollutants that may contaminate clean and freshwater sources if untreated or poorly treated. These toxic pollutants include colors; hazardous compounds; surfactants; cosmetics; agrochemicals; pharmaceutical by-products; and agricultural, pharmaceutical, and medical contaminants. Treating wastewater has become a global problem. Many projects have been started in the last two decades to treat wastewater, resultant water pollution, and associated waste management problems. Adsorbants based on graphene oxide (GO) are viable wastewater treatment materials due to their adaptability, photocatalytic action, and capacity for self-assembly. Here, we report the fabrication of nanofibrous mats from polycaprolactone (PCL), carboxymethyl arabinoxylan (CMARX), and carboxyl-functionalized-graphene oxide using an electrospinning technique. The silver nanoparticles were loaded onto the mat to enhance their photocatalytic activity. These mats were characterized using different techniques, including Fourier transform infrared (FTIR), scanning electron microscope (SEM), and transmission electron microscope (TEM). The water contact angles were used to study their hydrophilic and hydrophobic behavior. The Langmuir isotherm model and adsorption kinetics were studied to evaluate their adsorption capabilities against methylene blue (MB). Sample 2 followed the Langmuir isotherm model (R² = 0.9939). Adsorption kinetics exhibited pseudo-second order behavior (R² = 0.9978) due to their maximum correlation coefficient values. MB has excellent adsorption at room temperature and the formation of the monolayer at the surface of the adsorption mat. An enhanced PO₄³⁻ and MB adsorption was observed, providing recyclability up to 4–5 times. Hence, the fabricated nanofibrous mat would be a potential candidate for more effective wastewater treatment applications.