Efficient adsorption of Cu2+ using ZnCo bimetallic organic frameworks loaded cellulose-based modified aerogel: Adsorption behavior and mechanism

Cellulose has been broadly used in wastewater treatment . However, its adsorption capacity is limited by the lack of strong sites interacted with pollutants. Because of the good ability of carrying other substances, cellulose-based materials still have considerable room for improvement in adsorption capacity. Therefore, in virtue of this property, we synthesized a cellulose nanofibril (CNF) composite, Zn 0.5 Co 0.5 -ZIF@GEL aerogel , using mussel-bionic technique and zeolitic imidazolate frameworks (ZIFs) materials, which was applied in adsorbing copper ions . The experiments indicated the adsorption kinetics was consistent with the pseudo-second-order model. Langmuir model had a better fitting effect in isotherm analysis, revealing that the maximum adsorption capacity was 274.73 mg/g at 25 °C. Furthermore, we found that the appropriate doping of Co element to achieve an optimal synergistic effect enhance the adsorption capacity of Cu 2+ greatly. The mechanisms of synthesis and adsorption progress were also deeply researched. Overall, the findings of Zn 0.5 Co 0.5 -ZIF@GEL promote the application of ZIFs in the adsorption field of polydopamine-composited CNF aerogel . • The adsorbent used bionics techniques and metal organic frameworks (MOFs). • The synthesis of MOFs materials was easily operated. • The adsorption reached 70% of maximum adsorption capacity in a short time. • High maximum adsorption capacity (274.73 mg/g) at 25 °C was achieved for Cu 2+ . • The mechanism of Cu 2+ adsorption was investigated in detail.