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Highlights: [•] We engineered a simple, micro-object mesosensor based on aluminosilica pellets. [•] Ultra-fast and specific remote visualization and removal of multi-toxic metals were evident. [•] The sensor shows high stability, reproducibility, and versatility over ion detections. [•] Selective removal of Hg2+, Cd2+, and Cu2+ ions from drinking water and blood was evident. [Copyright &y& Elsevier]

Abstract: This study is an efficient arsenic(V) removal from contaminated waters used as drinking water in adsorption process by zirconium(IV) loaded ligand exchange fibrous adsorbent. The bifunctional fibers contained both phosphonate and sulfonate groups. The bifunctional fiber was synthesised by graft polymerization of chloromethylstyrene onto polyethylene coated polypropylene fiber by means of electron irradiation graft polymerization technique and then desired phosphonate and sulfonate groups were introduced by Arbusov reaction followed by phosphorylation and sulfonation. Arsenic(V) adsorption was clarified in column methods with continuous flow operation in order to assess the arsenic(V) removal capacity in various conditions. The adsorption efficiency was evaluated in several parameters such as competing ions (chloride and sulfate), feed solution acidity, feed flow rate, feed concentration and kinetic performances at high feed flow rate of trace concentration arsenic(V). Arsenic(V) adsorption was not greatly changed when feed solutions pH at 3.0–7.0 and high breakthrough capacity was observed in strong acidic area below pH 2.2. Increasing the flow rate brings a decrease both breakthrough capacity and total adsorption. Trace level of arsenic(V) (0.015 mM) in presence of competing ions was also removed at high flow rate (750 h−1) with high removal efficiency. Therefore, the adsorbent is highly selective to arsenic(V) even in the presence of high concentration competing ions. The adsorbent is reversible and reusable in many cycles without any deterioration in its original performances. Therefore, Zr(IV) loaded ligand exchange adsorbent is to be an effective means to treat arsenic(V) contaminated water efficiently and able to safeguard the human health. [Copyright &y& Elsevier]

Alkali treated tea waste (ATTW) was investigated as a novel alternative cost-effective natural adsorbent to decontaminate the pollutant of chromium (Cr(VI)) in the polluted water with the variation of equilibration time, solution pH, initial Cr(VI) concentration, adsorbent dosage, and temperature with a view to ensuring a safe disposal as well as sustainable management of the discarded bulk quantities of industrial tea leaves wastes. The adsorbent characteristic was confirmed the significant amount of Cr(VI) accumulation onto ATTW surfaces. The adsorption processes were satisfactorily described by pseudo-first order (PFO), pseudo-second order (PSO) and intra-particles diffusion models (IDM) where the PSO model evidently shows a better fitting with the regression coefficient (R 2 = 0.994). Exploration of Langmuir, Freundlich, Flory-Huggins, and Temkin isotherm models were also investigated and the best fitting was observed for the Langmuir model as it was produced the highest regression coefficient value (R 2 = 0.993). The maximum adsorption ability of ATTW according to the Langmuir model was found to be 158.73 mg/g. These results demonstrate that Cr(VI) adsorption was a complex process involving a physicochemical spontaneous monolayer and multiple rate-limiting states, which was predominantly chemical or chemisorption due to ion-exchange or electrostatic attraction/surface complexation formation, film diffusion and intra-particle diffusion. Furthermore, the substrates exhibited an excellent regeneration capacity upon using 0.10 M HNO 3 as eluent and ATTW was reused several cycles without influencing the adsorption performance. The results of this study thus concludes that ATTW could be a promising environmentally friendly and cheap bio-adsorbent for Cr(VI) remediation with profound implications in water and wastewater treatment for a large-scale environmental pollutant clean-up laden with toxic Cr(VI) ions. Unlabelled Image • A natural adsorbent was developed using alkali treated tea waste for pollutant removal. • The developed adsorbent demonstrated high adsorption to clean up wastewater efficiently. • The pollutant removal was predominantly governed by the chemisorption mechanisms. [ABSTRACT FROM AUTHOR]