Rapid co-sintering enables ultra-narrow pore size distribution ceria membranes for high-selectivity U(VI)/V(V) separation

A rapid co-sintering strategy is developed for CeO 2 nanofiltration membranes. • The membrane exhibits an ultra-narrow pore size distribution. • The membrane achieves a U/V separation factors of 326 in natural seawater. • The permeance reaches 21.6 L·m −2 ·h −1 ·bar −1 in natural seawater. • The strategy cuts fabrication time to 0.7 h and reduces energy consumption by 98.8%. Extracting uranium from seawater is essential for the sustainable development of nuclear energy. The highly selective uranium extraction remains challenging due to the extreme physicochemical similarity between uranium (U) and vanadium (V). Despite the sub-nanometer sieving capability of ceramic nanofiltration membranes, the conventional sintering required for structural integrity inevitably broadens the pore size distribution, thereby compromising selectivity toward closely sized ion pairs. This work proposes a rapid co-sintering (Co-RTP) strategy that utilizes radiation-induced ultra-fast heating and an adaptive co-sintering mechanism to construct a uniform CeO 2 selective layer within minutes, achieving a narrow pore size distribution (PSD) with a coefficient as low as 1.097. This ultra-narrow PSD effectively intensifies the U/V separation. In natural seawater, the membrane achieves a remarkable U/V separation factor of 326 and a permeance of 21.6 L·m −2 ·h −1 ·bar −1 . Moreover, the route reduces fabrication time from 110.6 h to 0.7 h and lowers energy consumption by 98.8%. This rapid co-sintering method provides a simplified and efficient fabrication route for precision ceramic membranes, and the resulting CeO 2 membrane holds great promise for challenging precision separations such as uranium extraction from seawater. Download: Download high-res image (222KB) Download: Download full-size image