Background: Constant current coulometry is one of the most precise methods in total uranium measurement

especially for pure uranium sample. Purpose: This study aims at the whole experimental flow conditions for total uranium measurement using constant current coloumetry. Methods: U3O8 and uranium standard solution were prepared. And various experimental conditions for phosphorus acid dosage

Fe(II) dosage

oxidizer dosage

oxidation temperature and coexisting ions etc.

were reviewed while measuring total uranium of samples with different weights of standard uranium solutions added in. Results: With optimized flow

total uranium weights in different uranium standard solutions were measured. For 50 mg total uranium added in

the combined uncertainty was 0.12% by constant current coulometry. Conclusions: This method can be used to measure total uranium content in pure uranium sample

and phosphorus acid plays a key role. When the concentration of phosphoric acid is more than 10 mol?L?1

the reduction reaction can be conducted at room temperature. Abstract