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The use of reverse osmosis (RO) for desalination holds great promise for addressing water scarcity issues in many parts of the world. However, membrane fouling is a significant impediment in this regard, as it reduces the quality and quantity of water produced, increases energy consumption, requires cleaning, and shortens membrane life. The use of granular activated carbon (GAC) adsorption in conjunction with ultrafiltration (UF) as a pre-treatment ensures that high-quality seawater enters the desalination process free of contaminants that could harm the plant. This method increases the efficiency and longevity of the equipment, lowers maintenance costs, and produces high-quality desalinated water for a variety of applications. In this study, GAC was made from commercially available charcoal and used to remove organic compounds, heavy metals, and microbiological contaminants from seawater. A preliminary study was conducted to determine GAC’s effectiveness in removing methylene blue (MB). The removal efficiency was found to be 78 and 99% at initial MB concentrations of 50 and 10 mg/L, respectively. The isotherm modeling confirms that the adsorption process follows the Langmuir model. In addition, the kinetic study demonstrated that MB adsorption on GAC follows the pseudo-second-order model. GAC filtration removed more than 99% of COD and significantly reduced metal concentrations such as Zn, Cu, and Cd. Bacteriological analysis of seawater treated with GAC revealed a significant reduction in total and fecal coliforms, as well as fecal streptococci, indicating the efficacy of the GAC/adsorption filtration system.

This comprehensive review delves into the recent advancements in the study of surfactant adsorption, a crucial factor influencing the efficiency of chemical enhanced oil recovery (cEOR) applications across various oil types. By integrating findings from the latest literature, we shed light on the dynamic interactions between surfactants and diverse adsorbents including sandstone, carbonate, and shale sandstone. This review highlights the nuanced understanding of how operational variables such as initial surfactant concentration, pH, adsorbent dose, contact time, temperature, along with adsorption kinetics, isotherm models, thermodynamics, and the presence of competing ions, contribute to the adsorption process. A novel synthesis of recent studies reveals that the Langmuir and pseudo-second-order models continue to accurately describe the equilibrium and kinetics of adsorption in most scenarios, with the adsorption process predominantly exothermic. Additionally, this review introduces cutting-edge insights into the molecular-level mechanisms underpinning surfactant adsorption, emphasizing the role of crude oil components, initial wettability of reservoir rocks, and the intrinsic properties of the rock itself. By summarizing these contemporary findings, the review aims to provide a deeper understanding of the key parameters affecting the retention of surface-active agents on various adsorbents, thereby proposing new avenues for optimizing surfactant flooding in cEOR. This enhanced focus on recent contributions to the field distinguishes our review from existing literature, offering fresh perspectives on the optimization of surfactant use in oil recovery processes.

The main purpose of this study was to improve sand filtration process by using local media and optimizing to obtain the best operating parameters. Sand from the Algerian desert was utilized. The treatment effectiveness on domestic effluent was assessed by monitoring pollution parameters such as turbidity, chemical oxygen demand (COD) and biological oxygen demand (BOD). The results of showed that the sand had a homogenous structure with a large presence of angular and blunted grains and a low percentage in round grains. This characteristic improves the filtration efficiency. The results showed also that the abatement rates of pollution indicators such as turbidity, COD and BOD were high for all experiments, between 60% and 90%. The sand filter designed in this study demonstrated a great performance for the treatment of domestic wastewater.

The main objective of this study was to demonstrate the efficiency and to optimize the operating conditions of photodegradation of paracetamol in the presence of suspended titanium dioxide catalyst in a photoreactor. An experimental design study was carried out using central composite design modelling. Optimization was applied to the tubular reactor under fixed photonic flux with radiation from two 24-watt UV-A lamps. The optimal values of the operating parameters were found to be pH of 7.288, TiO2concentration of 0.9932 g·L–1and paracetamol initial concentration of 15 mg·L–1. The paracetamol degradation rate approached 98.46% under optimal conditions. Modelling of the system led to a second-degree polynomial. Regression analysis gave an R2value of 0.977 which meant good agreement between the experimental results and the predicted values. An interaction was demonstrated between the catalyst and the operating parameters (pH, CParaand CTiO2) as well as between the model pollutant concentration and the pH had an insignificant effect on the yield compared to that of the quantity of the catalyst and the initial pollutant concentration.

In sustainable development context, solar energy may be adapted to improve the development of green technologies in wastewater treatment. In this paper, the photocatalytic elimination of Methylene Blue (MB) as a reference dye is performed in a fixed bed photoreactor. A commercial TiO2catalyst is immobilized on a cement support irradiated by solar light. The effects of some parameters such as the light source, pH of the solution as well as the pollutant initial concentration were investigated. The results show that the quantity of catalyst affects positively the MB degradation rate unlike the pollutant initial concentration which decreases the degradation efficiency. The degradation efficiency was found higher at around basic pH values (93%–97%). In addition, the degradation rate of pollutant was higher with solar light irradiation (97%) rather than with artificial irradiation (16%). This solar photocatalytic device is a potential application for organic dyes elimination.

AbstractThe non-biodegradability of textile wastewater is mainly due to the presence of synthetic dyes. Resistance to bacterial degradation led to the development of new techniques where solar photocatalysis appears to be the best method for this type of application. methylene blue (MB) degradation was studied in TiO2and ZnO aqueous suspension using solar energy in a tubular reactor. This study was conducted to evaluate the performance of the prototype and explore the feasibility of this concept for solar photocatalytic oxidation. The main objective of this work was to compare the efficiency of two types of catalysts, which are titanium dioxide (TiO2) and zinc oxide (ZnO). The use of TiO2as a catalyst enables a good degradation of MB which can achieve a disposal rate of 98% after 270 min with a TiO2concentration of 0.75 g/L. The same removal rate can be achieved by ZnO but for a much smaller concentration which was 0.025 g/L after 140 min.

The non-biodegradability of textile wastewater is mainly due to the presence of synthetic dyes. Resistance to bacterial degradation led to the development of new techniques where solar photocatalysis appears to be the best method for this type of application. methylene blue (MB) degradation was studied in TiO2and ZnO aqueous suspension using solar energy in a tubular reactor. This study was conducted to evaluate the performance of the prototype and explore the feasibility of this concept for solar photocatalytic oxidation. The main objective of this work was to compare the efficiency of two types of catalysts, which are titanium dioxide (TiO2) and zinc oxide (ZnO). The use of TiO2as a catalyst enables a good degradation of MB which can achieve a disposal rate of 98% after 270 min with a TiO2concentration of 0.75 g/L. The same removal rate can be achieved by ZnO but for a much smaller concentration which was 0.025 g/L after 140 min.