They showed adsorption capacities of 389.8-554.8 mg/g for Cu 2+ ions with a selectivity of 86.8% toward Fe 3+ ions . A filter paper containing cellulose and ZIF-8 were reported . The prepared filter paper, denoted as CelloZIFPaper, was used for heavy metal adsorption. The materials offered adsorption capacities of 66.2-354.0 mg/g. CelloZIFPaper was also tested as a flexible electrode for toxic heavy metal detection . The reader can directly go to our recent Review on the topic of cellulose-MOF composite (denoted as CelloMOF) and their applications . CelloMOF enabled multifunctional applications being efficient adsorbents and catalysts . ZIF-8 was also reported for the recovery of rare-earth elements . Magnetic nanoparticle-modified MOF materials were reported for heavy metal adsorption and removal . Fe3O4@ZIF-8 and Fe3O4@UiO-66-NH2) were investigated for the adsorption of Cd 2+ and Pb 2+ ions. Fe3O4@UiO-66-NH2 and Fe3O4@ZIF-8 offered adsorption capacities of 714.3 mg/g, and 370 mg/g for Cd 2+ , respectively, and 833.3 mg/g, and 666.7 mg/g for Pb 2+ , respectively .