Fabrication of a Magnetic Cellulose Nanocrystal/Metal-Organic Framework Composite for Removal of Pb(II) from Water

A novel composite material (MCNC@Zn-BTC) is synthesized from magnetic cellulose nanocrystals (MCNC) and a metal-organic framework (MOF), based on Zn(II) and benzene-1,3,5-tricarboxylic acid (Zn-BTC), using a simple mechanical agitation method at room temperature. The developed MCNC@Zn-BTC was characterized by SEM, TEM, FTIR, XRD, XPS, and VSM instruments. The impact of MCNC@Zn-BTC dose, initial Pb(II) concentration, contact time, pH, and adsorption temperature have been explored. Results demonstrated that only 30 min was needed to achieve the adsorption equilibrium; the maximum adsorption capacity was 558.66 mg/g at 298.2 K. Besides, data obtained were fitted to a Langmuir isotherm model (R-2 = 0.9890), and the adsorption kinetics followed a pseudo-second-order model. In addition, the removal (%) of Pb(II) remained greater than 80% after five recycled times. Therefore, the novel MCNC@Zn-BTC adsorbent displays great potential to improve the quality of environmental water contaminated with heavy metals.