Preparation of NiAl-LDH/Polypyrrole composites for uranium(VI) extraction from simulated seawater

In this work, NiAl-LDH/Polypyrrole (NiAl-LDH/PPy) was synthesized by a simple method for the adsorption of uranium(VI) (U(VI)) from simulated seawater. The parameters studied contained pH, contact time, initial concentration and temperatures. The kinetic parameters showed that it could be well consistent with pseudo-second-order model. Langmuir and Freundlich isotherm models were used to describe the equilibrium data at three different temperatures (25, 35 and 45 °C). The result confirmed that the adsorption equilibrium tend to follow Langmuir isotherm model and the maximum adsorption capacity was evaluated to be 406.5 mg/g at 45 °C. The adsorption was a spontaneous endothermic process. NiAl-LDH/PPy also had good reproducibility and selectivity. In simulated seawater, NiAl-LDH/PPy composites showed a good enrichment effect for U(VI).