The Removal of Uranium From Simulated Ammonium Diuranate Filtrate by Nanofiltration Available to Purchase

In this study, a simulated ammonium diuranate filtrate (ADUF) which was obtained by adding uranyl nitrate to a 35 g/L ammonium nitrate solution to adjust the uranium concentration to about 50 mg/L was treated by a nanofiltration process. Experiments were carried out on a plate membrane testing device with a trans-membrane pressure (TMP) range of 0.5 ∼ 3.0 MPa, a crossflow velocity range of 10 ∼ 50 cm/s and a temperature range of 5 ∼ 35 °C. The results show that NF270 membrane has good rejection property for uranium and excellent permeability for ammonium nitrate. The ammonium nitrate concentration in the permeate is about 32 g/L which means the reject ratio of ammonium nitrate is only about 10%. Though NF270 membrane shows good uranium rejection property, the corresponding permeate flux is very high. When the trans-membrane pressure is 1.5 MPa, the uranium reject ratio is 96.8% and the the corresponding permeate flux is about 80 L/(m²·h). It indicates a bright application prospect of nanofiltration process in the treatment of ADUF.