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This study aims to optimize the preparation conditions and modify the nanofiltration (NF) membranes to prepare high-performance polysulfone/sulfonated polysulfone composite nanofiltration (PSF/SPSF-NF) membranes through interfacial polymerization.

Investigating the impacts of anhydrous piperazine (PIP) concentration, trimesoyl chloride (TMC) concentration and basement membrane type on NF membrane performance, the optimal membrane was prepared. In addition, nano-SiO₂ was added to the active separation layer to modify the NF membranes.

The comprehensive performance of PSF/SPSF-NF membranes was optimized when the concentration of PIP was 0.75 Wt.% and the concentration of TMC was 0.15 Wt.%, at which time the water flux was 66.1 L·m⁻²·h⁻¹ and the retention rate of Na₂SO₄ was 98.1%. The comprehensive performance of polysulfone/sulfonated polysulfone-SiO₂ nanofiltration (PSF/SPSF-SiO₂-NF) membranes was optimized when the blending ratio of nano-SiO₂ to PIP was 2:3, with a pure water flux of 81.9 L·m⁻²·h⁻¹ and a Na₂SO₄ retention rate of 95.9%. Compared to polysulfone nanofiltration (PSF-NF) membranes and PSF/SPSF-NF membranes, NF membranes with nano-SiO₂ increased the flux recovery rate by 22.9% and 8.7%.

PSF/SPSF-SiO2-NF membrane exhibits excellent antifouling properties.

There is currently no literature available on the preparation of NF membranes using polysulfone/sulfonated polysulfone (PSF/SPFS) as a substrate. This provides a method for modifying NF membranes, starting with the modification of the basement membrane and then modifying the active separation layer.

The main purpose of this paper is to investigate the adsorption properties of CoFe_1.9Mo_0.1O₄ magnetic nanoparticles (CFMo MNPs) using, anionic dye “congo red (CR)” as a model of water pollutants.

The magnetic nano-adsorbent was synthesized via sol-gel process. Different techniques including; Fourier transform infrared spectroscopy, point of zero charge, scanning electron microscope and X-ray powder diffraction were used to characterize the prepared adsorbent. Adsorption experiments were conducted in batch mode under various conditions (contact time, shaking speed, initial dye concentration, initial solution pH, solution temperature and adsorbent amount) to investigate the adsorption capability of CFMo MNPs for CR.

The results showed that, CFMo MNPs could successfully remove more than 90% of CR dye within 20 min. Adsorption kinetics and isotherms were better described using pseudo-second-order (PSO) and Langmuir models, respectively. The maximum adsorbed amount (q_max) of CR dye was 135.14 mg/g. The adsorption process was found to be endothermic and spontaneous in nature as demonstrated by the thermodynamics ( ΔGo, ΔHoand ΔSo).

This study provided a good example of using an easily separated magnetic nano-adsorbent for fast removal of a very toxic organic pollutant, congo red, from the aquatic environment

The employment of Mo-doped cobalt ferrite for the first time for removing hazardous anionic dyes such as congo red from their aqueous solutions.

This study aims to develop a sol-gel-based coating to provide a long-lasting corrosion protection on AZ31 Mg alloy. Silane-based sol-gel coatings have been successfully applied to Mg alloys for corrosion protection. However, the micro or nano defects formed during condensation and solidification will cause the coating failure during a long-lasting immersion in a saline solution. More durable corrosion-protective sol-gel coatings are needed.

A sol-gel-based coating was modified on AZ31 Mg alloy by levodopa (DOPA). The long-lasting corrosion protection mechanism was studied by multiple electrochemical testing methods and surface characterization techniques.

Long-term testing by electrochemical impedance spectroscopy in aqueous 0.1 M NaCl indicated that the modified DOPA@sol-gel coating exhibited significant corrosion protection performance (>14 days). In comparison, the DOPA-free sol-gel coating failed only after three days of testing. The improved corrosion protection is attributed to the self-polymerized DOPA filling to the micro or nano defects in the glassy cross-linked networks of the sol-gel coating, which greatly improves the compactness of the coating.

The method of this study is simple and easy to process, the raw materials are green and the protective effect is excellent, which is of significance for the study of magnesium alloy corrosion protection.

The textile industry is one of the largest and most important industrial sectors in India. Because the textile industry consumes large quantities of water and produces highly polluted water discharge, its environmental impact is high. Water is expensive to use, treat and dispose of. Therefore, water conservation and reuse are critical necessity for the textile industry because decreasing water and wastewater treatment and recycling costs can be beneficial.

This research neutralized the pH during dyeing industry wastewater treatment. The system should be robust to erroneous sensor measurements. A pH meter was developed and used to monitor the pH of wastewater hourly before and after HCl treatment.

HCl was used to neutralize the pH of wastewater from 9 to 7.5. The amount of HCl was optimized depending on the wastewater. Three wastewater treatment methods were used, namely, HCl, wash water and reverse osmosis (RO) treatments. The HCl treatment was the most effective for decreasing the pH; the wash water treatment was the most effective for decreasing the total dissolved solids (TDS), total suspended solids (TSS) total hardness and chemical oxygen demand; and the RO treatment was the most effective for decreasing the biochemical oxygen demand, TDS, TSS, total hardness and Cl⁻ concentration.

The pH should be monitored during the textile dyeing because the addition of color to textile fabrics is the most effective at neutral pH. This study evaluated several parameters of wastewater, including pH, color, TSS and TDS. The fabricated digital pH meter provided superior results than conventional measuring devices. The goal was to maintain a neutral pH during dyeing and recycle wastewater to improve environmental sustainability. The newly developed digital pH meter was less expensive and more precise than traditional pH meters. Before reusing and recycling, wastewater underwent ultrafiltration and RO treatment.