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• A novel tailored ion-imprinted polymer for recovery of Li+ and Sr2+ was prepared. • The brine sample showed a higher Li+ and Sr2+ concentration of 43.32 mg/L and 16.93 mg/L, respectively. • Q m was increased as the temperature rise from 714 mg Li+/g at 25 °C to 2500 mg Li+/g at 45 °C. • Li+ desorption results show that 94.03% − 94.71% of the ions were recovered. • The IIP efficiency to adsorb Li+ from brine was 84.68%, and 10% for Sr2+. This study aims to prepare ion-imprinted polymer (IIP) with the benefit of a metal-based sorbent, which is fabricated to selectively adsorb lithium (Li+) from aqueous solutions, and in an attempt to remove strontium (Sr2+). The adsorption processes were carried out at different pH values, initial concentrations, and temperatures, to optimize the experimental conditions, with the use of response surface methodology (RSM). The seawater reverse osmosis (SWRO) brine was physically and chemically characterized, and the physicochemical characterization of the prepared IIP before and after adsorption was also performed using different spectroscopic methods. The adsorption capacity for Li+ and Sr2+ from SWRO brine was evaluated, and the reusability of IIP was investigated using adsorption–desorption cycles. The results showed that the IIP was efficient to remove Li+ but not Sr2+, and it follows Freundlich adsorption isotherms models. The analysis revealed a significant concentration of minerals in the brine sample It also revealed a low concentration of trace metals, like Ba (0.16 mg/L), Zn (0.845 mg/L), Fe (1.31 mg/L), Cu (1.165 mg/L), Pb (1.505 mg/L), and V (3.88 mg/L), except Li and Sr which shows a higher concentration of 43.32 mg/L and 16.93 mg/L respectively. pH 10 was selected to be the optimum pH for the adsorption isotherm experiments, as it was the highest efficient pH to adsorb Li+ and Sr2+. The thermodynamics study revealed that the adsorption of Li+ on the IIP favored exothermic conditions. It was noticed that the maximum adsorption capacity (Q m) was increased as the temperature rise from 714.3 mg/g at 25 °C to 2500 mg/g at 45 °C. The Li+ desorption results show that 94.03% − 94.71% of the ions were recovered, while the Sr2+ desorption results show that 96.35% − 96.56% of the ions were recovered. The efficiency of IIP to adsorb lithium and strontium from brine shows that the adsorption removal% of Li+ was between 84.21% and 84.68%, while the adsorption removal% of Sr2+ was between 3.83% and 10%. The cost analysis for IIP preparation was 2 USD/g. [ABSTRACT FROM AUTHOR]

Commercial diesel is often loaded with organosulphur compounds including hard-to-remove dibenzothiophene DBT and other derivatives. Following uncommon and simple procedure, dibenzothiophene was selectively removed upon diesel acidification by acetic acid prior to activated carbon adsorption. Initially, competitive adsorption tests from synthetic fuel proved that dibenzothiophene is preferentially removed over di/tri and tetra-aromatic hydrocarbons upon fuel acidification by 5% ( by vol .) acetic acid. The efficacy of the proposed method was further validated by removing dibenzothiophene from commercial diesel containing 2578 (±15) mg kg −1 . The removal of DBT from complex diesel has increased from 27% to 55% upon acidification by 5% acetic acid. Acidity value of the treated diesel is within the regulated limit giving more chance for the new procedure for practical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Positively charged PEI improved deposition and orientation of GO on PSf. • Synergic effects of PEI-modification and GO govern the formation of PA. • A thin but rough PA is formed on the surface of PEI-modified PSf substrate. • PEI-interlayer TFN membrane showed greater water flux without affecting rejection. In this work, the polyethyleneimine (PEI)-interlayered thin film nanocomposite (iTFN) membranes were developed by establishing graphene oxide (GO)-incorporated polyamide (PA) layer atop PEI-coated polysulfone (PSf) substrate for reverse osmosis process. The effects of PEI layer sandwiched between selective layer and substrate were studied by varying several main parameters of the PEI coating process, i.e., PEI concentration (0.005–0.2 wt/v%), drying time (0–120 min), and coating layer number (1–3 layers). The positively charged PEI interlayer was found to alter not only the hydrophilicity and pore structure of the substrate but also improve the orientation and distribution of deposited GO through electrostatic interaction. Synergic effects of GO and PEI, including enhanced substrate surface hydrophilicity and increased amine content, eventually formed a rough but thin PA layer. As a result, almost all iTFN membranes exhibited higher NaCl rejection and water permeability than the control TFN membrane (without PEI intermediate layer). This experiment revealed that PSf substrate modified with a single layer of 0.05 wt/v% PEI followed by 60-min drying yielded the TFN membrane (i.e., iTFN-C0.05-T60-L1) with the best desalination performances (96.66% NaCl rejection and 2.24 L/m2·h·bar). The control TFN membrane meanwhile showed lower performance, i.e., 95.61% NaCl rejection and 1.69 L/m2·h·bar. [ABSTRACT FROM AUTHOR]

• Electrokinetic and rheological behavior of treated bentonite suspension were studied. • NADES showed better performance compared to ChCl-LA mixture. • NADES treated suspensions showed pseudoplastic and time-dependent behavior. • Solid-like behavior ( G ' > G ' ' ) was observed in all treated suspensions. • The destabilization degree and rheological behavior were in good agreement. Colloids in wastewater are considered a serious problem due to their stability and separation difficulty. Coagulation/ flocculation processes are the most common for the separation of colloids because of their high-performance efficiency, simplicity, and economical characteristic. Natural deep eutectic solvents (NADES) are green solvents that proved to be highly effective in the destabilization of colloidal suspensions. In the present study, the influence of choline chloride (ChCl) and lactic acid (LA) based NADES on the rheological behavior of bentonite suspension was investigated. Furthermore, it examines the difference in the rheological behavior of NADES treated suspension with others treated with ChCl-LA mixture (LA and ChCl added one after the other). The rheological behavior are correlated to the destabilization degree of each coagulants through turbidity reduction, zeta potential, particle size distribution, and capillary suction time. The study revealed that while untreated bentonite suspension follows a Newtonian behavior, treated suspensions are non-Newtonian fluids with shear thinning behavior. Furthermore, all treated suspensions showed elastic behavior under moderate to low oscillatory frequencies. The changes in the studied rheological parameters (i.e., initial viscosity, elastic modulus, and Bingham yield stress) were influenced by the concentration in addition to the structure of the selected coagulant. The addition of higher coagulant concentration enhances the elastic properties from two to more than ten times depending on the concentration and coagulant type. At concentration of 6.76 × 10 - 2 M , suspension treated with NADES achieved an initial viscosity of 194 , 110 m P a. s and a yield stress of 2959.3 m P a which indicates the formation of stronger and stiffer flocs. On the other hand, ChCl-LA treated suspension had viscosity and yield stress of 9 and 15 magnitudes lower, respectively. Enhancing the rheological behavior of suspensions is usually attributed to higher destabilization degree, which is desirable for the further treatment processes. By increasing the concentration from 5.9 × 10 - 3 M to 6.76 × 10 - 2 M , turbidity reduction increases from 12 % to 99.9 % with an increase in the floc size from 3.3 μ m to 27.3 μ m for NADES treated suspension. The increase in the destabilization degree was associated with an enhancement in the suspension viscosity by more than two folds. [ABSTRACT FROM AUTHOR]

• Hybrid coagulation-flocculation on the flocculation of bentonite is investigated. • Compared to single PAM, hybrid systems performed exceptionally well. • Hybrid systems were able produce bigger flocs than single systems. In this study, the influence of the hybrid coagulation-flocculation system on the flocculation and shear resistivity of bentonite suspension has been investigated. Two short-chained coagulants, polyamine and polyDADMAC, accompanied with low and high Molecular Weight (Mw) long-chained anionic Polyacrylamide (PAM) flocculants have been used to enhance the size and mechanical properties of the produced flocs. Four characterization techniques were used as evaluation criteria of degree of flocculation including turbidity, zeta potential (ζ), floc size analysis and rheology. Optimum dosages between 5 and 10 mg/L were obtained for flocculants and between 20 and 30 mg/L for coagulants in hybrid systems. Compared to single systems, hybrid systems performed exceptionally well. Removal efficiency of 99% was achieved using hybrid systems producing water with turbidity as low as 1.05 NTU. Although differences were insignificant in the treatment quality, significant improvement was achieved in floc size and rheological behavior. Hybrid systems were able to produce large flocs of more than 400 µm, five times bigger than flocs from the single cationic coagulant systems. Most importantly, rheological testing of produced slurries revealed the remarkable advancement achieved by hybrid systems. Hybrid systems were able to increase the elastic modulus (G′) by more than ten times resulting from the compacted flocs present in the system. Furthermore, resistivity toward shear and oscillations were improved. Ultimately, hybrid systems have surpassed the single cationic systems by achieving slightly better treatment besides producing larger, denser and more resistive flocs. Generally, polyDADMAC performed better than polyamine in hybrid systems. The combination of polyDADMAC with high Mw PAM gave the best separation as well as the largest flocs, while the combination with low Mw PAM resulted in the best rheological properties. [ABSTRACT FROM AUTHOR]