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A novel CMC/PVA/MIL-101(Cr) bead (CPMB) with tailored network and affinity sites was prepared by the green polymer matrix of CMC and PVA and nanofiller of MIL-101(Cr) through the simple complexing with the ionic crosslinking agent for efficient capture of heavy metal ions in wastewater. [Display omitted] • Intermolecular H-bonds of CMC/PVA matrix enhanced stable properties of adsorbents. • Adding MIL-101 to the matrix improved specific surface areas and offered active sites. • Synthesis of CMC/PVA/MIL-101(Cr) beads with increased the affinity for targeted ions. • High recycling adsorption performance even after eight cycles at testing conditions. A novel CMC/PVA/MIL-101(Cr) aerogel bead (CPMB) was prepared by the green polymer matrix of CMC and PVA and nanofiller of MIL-101(Cr) through the simple complexing with the ionic crosslinking agent, which could be an adsorptive platform for effectively capturing of Co(II) and Ni(II) ions in wastewater. The morphology, surface chemistry, and textural characteristics were investigated by varied characterization methods to reveal behind mechanisms for the dissimilarity in adsorption performance. The optimal modifying dosage of MIL-101(Cr) nanoparticles was determined to form an optimal tailored network with abundant MIL-101 clusters and hydroxyl/carboxyl groups inside the network that greatly achieved the most accessible heavy metals to CPMB-1. Meanwhile, the influences of temperature, adsorption dosage, pH, and interfering cations on the capacity of CPMB-1 were investigated, while adsorption behaviors of adsorbents were also explored. Analytic results indicated that the capture of two targeted ions by CPMB-1 could favorably comply with the Pseudo-second-order kinetic model and Freundlich isothermal adsorption model. The maximum adsorption capacities of two targeted ions calculated by data were 180.3 mg/g and 261.9 mg/g, respectively. According to the results of XPS and FTIR analysis, the electrostatic attraction and chelating effect could be the main mechanisms for improved performance, and contributing groups were the hydroxyl and carboxylic acid introduced into CPMB-1. Moreover, the as-designed CPMB-1 exhibited excellent recyclability and stability in eight cycles. The encouraging results exhibited by CPMB-1 might bring a new idea for integrating multiple functionalities of MOFs and biomass components for designing functional composites for efficient remediations of wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new adsorbent was synthesized by modifying Zr-MOF with Ni 0.6 Fe 2.4 O 4 and PEI. • The adsorbent showed sufficiently magnetic strength, good thermal and acid-base stability. • The theoretical adsorption capacities of Pb(II) and Cr(IV) were 273.2 mg/g at pH 4.0 and 428.6 mg/g at pH 3.0. • The adsorbent was renewable and selective. A novel magnetic Zr-MOF named Ni 0.6 Fe 2.4 O 4 -UiO-66-PEI was synthesized by modifying UiO-66-NH 2 with Ni 0.6 Fe 2.4 O 4 and polyethyleneimine and its sorption characteristics for two representing heavy metals Pb(II) and Cr(VI) in water were examined. This material showed good thermal stability and was sufficiently magnetic to allow effective solid-liquid separation. The material had a maximum adsorption capacity of 273.2 mg/g for Pb(II) at pH 4.0 and 428.6 mg/g for Cr(VI) at pH 3.0, as obtained from the model fitting by the Hill equation. The sorption kinetics for both heavy metals on the material was fast, with adsorption equilibrium established in 60 min and 30 min for Pb(II) and Cr(VI), respectively. Model fitting of the kinetic data showed that Pb(II) and Cr(VI) sorption on Ni 0.6 Fe 2.4 O 4 -UiO-66-PEI followed the pseudo-second-order model. This material had good selectivity for competing ions, and still hold fairly good binding capacities after 5 times of regeneration. Adsorption mechanisms for Pb(II) and Cr(VI) by Ni 0.6 Fe 2.4 O 4 -UiO-66-PEI were proposed by analyzing FTIR, XPS and the electrokinetic property of the material. Specifically, Pb(II) adsorption on Ni 0.6 Fe 2.4 O 4 -UiO-66-PEI could be attributed to chelation of Pb(II) with the imine/amine functional groups in the material's matrix, while Cr(VI) adsorption might stem from a combination of electrostatic attraction, chelation and redox reaction. It seems that Ni 0.6 Fe 2.4 O 4 -UiO-66-PEI could be used as a green and environmental-friendly material for heavy metals removal, particularly from acidic water streams. [ABSTRACT FROM AUTHOR]