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[Display omitted] • Novel and recyclable ZIF-90@CS/SA hybrids were successfully synthesized. • Maximum adsorption capacity of Pb and Co by ZIF-90@CS/SA was 1.24 × 10−3 mol/g and 1.69 × 10−3 mol/g, respectively. • ZIF-90@CS/SA displayed remarkable stability in the elimination of Pb and Co. • Surface complexation and electrostatic attraction were primary interactive mechanisms. • Long-term field studies on Pb and Co behaviors in water medium were required. Efficient elimination of heavy metals contaminations can be extensively concerned by utilizing environmental-friendly adsorbents with pursuing high adsorption capacity and reducing the treatment costs of industrial sewage. Herein, the core–shell structured chitosan/sodium alginate polysaccharide polymers loading zeolite imidazolate framework-90 beads (ZIF-90@CS/SA) were successfully synthesized and analyzed to obtain efficient enrichment performances for Pb and Co. The ZIF-90@CS/SA beads were multifariously characterized through the superficial micropore structures, which included both before and after adsorption performance of Pb and Co from the macroscopical experiments. The optimal weight ratio of chitosan/sodium alginate was chosen 1:2 to prepare ZIF-90@CS/SA beads by drop-method, and then adsorption experiments of Pb and Co were also conducted under various water chemistry conditions. The especial adsorption equilibrium time for the elimination of Pb and Co through the ZIF-90@CS/SA beads was 2.5 h and 3.5 h respectively, which was in accordance with pseudo-second order pattern. The maximal adsorption capacity was respectively 1.24 × 10−3 mol/g for Pb and 1.69 × 10−3 mol/g for Co, which considerably improved in comparison with many previously reported adsorbents. The adsorption mechanisms of ZIF-90@CS/SA beads with Pb and Co were dominated by the surface complexation, ion exchange and electrostatic attraction. According to macroscopical experimental studies, the ZIF-90@CS/SA beads have promising applications in the field of sewage treatment with highly efficient enrichment, advantageous regeneration and purfication of numerous heavy metal contaminants. [ABSTRACT FROM AUTHOR]

Extraction of radionuclide contaminants from wastewater systems has recently drawn widespread attention, and then developing a novel and green extracting technology has also become an enormous challenge. Herein, a facile hydrothermal method was employed to fabricate cobalt-incorporated cryptomelane-type manganese oxide molecular sieve (Co-OMS-2) for extraction Eu(III) from wastewater under diverse experimental conditions. All kinds of characterized techniques, such as SEM, TEM, XRD, FTIR, BET, EDS and XPS had verified the qualified synthesis process and splendid structural features of the Co-OMS-2. The maximum adsorption capacity of Co-OMS-2 was 7.62 × 10−4 mol/g for Eu(III) at 298 K, which was superior than primarily traditional materials reported previous literatures. The high adsorption capacity of Eu(III) onto Co-OMS-2 was primarily attributed to high specific surface area and abundant surface functional groups, and the interactions were mainly contributed to strong surface complexation and electrostatic attraction. Under the condition of low pH, the outer-sphere surface complexation and cation exchange were primary mechanisms to Eu(III) adsorption onto Co-OMS-2 composites, while inner-sphere surface complexation was mainly assigned to Eu(III) adsorption onto Co-OMS-2 under the high pH sections. The Co-OMS-2 composite achieved equilibrium in a relatively short time, and this excellent performance was conducive to the treatment of Eu(III) under the extreme emergency conditions. In view of the extraordinary adsorption capacity and recycled reusability, the Co-OMS-2 composites can be as prospective adsorbents adopted for the extraction of Eu(III) in real wastewater management. • Oriented functionalization of Co-OMS-2 was successfully synthesized. • The maximum adsorption capacity of Eu(III) by Co-OMS-2 was 7.62 × 10−4 mol/g. • Co-OMS-2 displayed remarkable stability in the elimination of radionuclides. • The surface complexation and ion exchange were the main interaction mechanisms. [ABSTRACT FROM AUTHOR]

• Oriented functionalization of UiO-66-PO 4 was successfully prepared. • The maximal adsorption capacity of Eu(III) by UiO-66-PO 4 was 3.86 × 10-4 mol·g−1. • UiO-66-PO 4 revealed excellent stability in the removal of radionuclides. • The surface complexation and electrostatic interaction were primary mechanisms. • Long-term evaluation of Eu(III) performances in aqueous medium were needed. Herein, phosphorylation modified zirconium-based metal–organic frameworks composites (UiO-66-PO 4) were synthesized by facile and green approach, which was employed to remove Eu(III) from water solution under various experimental conditions. The macroscopic experiments showed that the removal performance of Eu(III) onto the UiO-66-PO 4 composites was endothermic and spontaneous with the tremendous phosphate groups acting as critical binding sites. The SEM, XRD and FTIR provided beneficial evidence for propitious phosphate group grafted onto UiO-66 surfaces. The removal performance of Eu(III) onto UiO-66-PO 4 composites followed the pseudo-second-order model and the adsorption isotherms were well simulated by Langmuir model. The maximum adsorption capacity of UiO-66-PO 4 composites toward Eu(III) was calculated to 3.86 × 10-4 mol·g−1 using Langmuir model. The UiO-66-PO 4 hybrids having excellently stable could be easily regenerated with no observed significant reduction in the elimination of Eu(III) even after five consecutive cycles. Furthermore, the XPS spectra results further revealed that those including zirconium, phosphate and oxygen functional groups played significantly role in the restricting of europium onto UiO-66-PO 4 surfaces. The experimental results further illustrated that the interactive mechanisms of Eu(III) onto UiO-66-PO 4 hybrids were primarily attributed to the outer-sphere surface complexation at low pH values and then inner sphere surface complexation at high pH values. Based on the discussed results, the UiO-66-PO 4 composites can be as promising candidates with favorably recycled reutilization for the elimination of europium from wastewater systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Zn-Al LDH/SDS/MWCNTs was synthesized through a green method. • Zn-Al LDH/SDS/MWCNTs presented high adsorption rate and capacity towards Congo red. • Interaction mechanism of as synthesized samples was revealed by various characteristic approaches. • Zn-Al LDH/SDS/MWCNTs composites have excellent adaptability to the environment. Herein, high-activityand petal-like Zn-Al layered double hydroxide/multiwalled carbon nanotubes supported sodium dodecyl sulfonate (Zn-Al LDH/SDS/MWCNTs) composites were successfully synthesized as novel, eco-friendly and effective adsorbents. The particularly physical and chemical properties of Zn-Al LDH/SDS/MWCNTs composites were characterized in detail. Besides, the adsorption performance and interaction mechanism of Congo red onto Zn-Al LDH/SDS/MWCNTs were also investigated under various experiment conditions. The initial pH values and adsorbent concentration played significant part in adsorption performance of Congo red dye. The adsorption kinetics and temperature-dependent isotherms of Congo red onto Zn-Al LDH/SDS/MWCNTs were respectively consistent with pseudo second-order model and Langmuir model. The maximum adsorption capacity of Congo red was greatly achieved to 1.42 × 10−3 mol/g adopting Langmuir model, which was much better than those previously reported other composites to date. The experimental results illustrated that the adsorption performance of Congo red onto Zn-Al LDH/SDS/MWCNTs composites was primarily contributed to surface complexation, ion change, π-π interaction, electrostatic interaction together with hydrogen bond to some extent. The experimental results demonstrated that the as-synthesized Zn-Al LDH/SDS/MWCNTs composites are remarkable adsorbents for the wastewater treatment systems. Our study initials a new foresight for understanding the interaction mechanism and preparing highly efficient and eco-friendly adsorbents with excellent adsorption performance for the elimination of organic contaminants. [ABSTRACT FROM AUTHOR]