Deeply removal of trace Cd2+ from water by bacterial cellulose membrane loaded with nanoscale zerovalent iron: Practical application and mechanism

•BCM-nZVI exhibit adsorption capacity of 134 mg·g−1 and Cd2+ removal rate of 99.96%.•Cd2+ in water treated by BCM-nZVI is below drinking water standards (5 μg·L-1).•BCM-nZVI can be stored stably for 120 days without loss of activity.•The adsorption mechanism by reducing toxic Cd2+ to non-toxic Cd0 is revealed.