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This review focuses on the occurrence and interactions of engineered nanoparticles (ENPs) and brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) in water systems and the generation of highly complex compounds in the environment. The release of ENPs and BFRs (e.g. PBDEs) to aquatic environments during their usage and disposal are summarised together with their key interaction mechanisms. The major interaction mechanisms including electrostatic, van der Waals, hydrophobic, molecular bridging and steric, hydrogen and π-bonding, cation bridging and ligand exchange were identified. The presence of ENPs could influence the fate and behaviour of PBDEs through the interactions as well as induced reactions under certain conditions which increases the formation of complex compounds. The interaction leads to alteration of behaviour for PBDEs and their toxic effects to ecological receptors. The intermingled compound (ENPs-BFRs) would show different behaviour from the parental ENPs or BFRs, which are currently lack of investigation. This review provided insights on the interactions of ENPs and BFRs in artificial, environmental water systems and wastewater treatment plants (WWTPs), which are important for a comprehensive risk assessment.

The electrochemical synthesis of ammonia using nanolayered catalyst of RuO2 and CeO2 on a 3D-Graphene support at an ambient condition, demonstrates excellent NRR activity with long-term stability.

The continuous increase of demand for lithium (Li) chemicals in industrial applications calls for exploring affordable Li production and sustainable options beyond land mining. Thus, aqueous resources, such as geothermal brine, salt lake brine, and seawater, play an essential role in continuous Li supply due to abundant storage and low cost. Adsorption technology is promising in Li recovery with the advantages of attaining high selectivity for Li over other major ions present in aqueous resources at low cost and low energy demand with facile synthesis processes that enable practical large-scale production. Metal-based adsorbents are conspicuous among various adsorbents for presenting the visible prospect closest to industrial applications. This review presents a comprehensive summary and critical analysis of the synthesis methods for metal-based adsorbents, the mechanisms for Li selective recovery, and the performance of Li adsorption. The advantages and challenges are discussed for different adsorbents and preparation methods. A specific focused case study on an industrial application of Al-based adsorbent production and Li recovery processes and operations on an engineering and economic scale is discussed in detail to provide a comprehensive overview of the practical industrial application of metal-based adsorbent.

Human urine contains high concentration of pharmaceuticals, a concern that must be addressed if used as a fertiliser. This study systematically evaluated granular activated carbon (GAC) adsorption in removing five most commonly found pharmaceuticals in the environment – naproxen (NAP), carbamazepine (CBZ), ibuprofen (IBP), acetaminophen (APAP) and metronidazole (MTZ) from hydrolysed urine. Fixed-bed column experiments were conducted to obtain breakthrough curves and assess GAC (1000 m2g−1) performance in the adsorption of pharmaceuticals at different adsorbent mass (4–12 g·L−1), flow rate (1.15–4.32 L·d−1) and adsorption/contact time at ambient room temperature and pH 9. The highest adsorption capacity was observed at a lower adsorbent mass (4 g·L−1) and lower flow rate (1.15 L·d−1) for all micropollutants. The breakthrough curves showed the highest GAC adsorption capacity for CBZ (56.1 mg·g−1) while MTZ (32.2 mg·g−1) with the lowest adsorption will be the design limiting for column adsorption application. Thomas and Yoon-Nelson models fitted well for predicting empirical breakthrough curves for fixed-bed GAC column adsorption. The artificial neural network (ANN) modelling was able to predict the removal effectiveness of over 99% except for APAP at 84.5%. The study showed that the potential application of GAC column adsorption for micropollutant removal is significant although this study was limited in the range of parameters studied.

The electrochemical synthesis of ammonia at ambient temperature and pressure has the potential to replace the conventional process for the production of ammonia. However, the low ammonia yield and poor long-term stability of catalysts for the synthesis of ammonia hinders the application of this technology. Herein, we endeavored to tackle this challenge by synthesizing 3-D vertical graphene (VG) on Ni foam