Abstract: A novel method for determination of uranium in sea water with sodium polyphosphate as fluorescence intensifier was reported. It was found experimentally that quantitative determination of trace uranium was achievable with a 10-fold dilution by deionized water,the solution pHset to 2-3 and a concentration of sodium polyphosphate of 0.58%. The relative deviation of duplicate analysis is 4.3%-6.2%,and the recovery of standard addition is 95.0%-98.2%. Its detection limit is 0.16-0.22 μg/L.

Key words: Sodium polyphosphate, Fluorescence intensifier, Sea water, Trace uranium