Segment Flow Analysis Applied to the Determination of Ammonia Nitrogen in Water

By the use of the reaction among NH+4,hypochlorite and alkaline solution of phenol,catalyzed by sodium nitroferricyanide,to produce a blue colored complex (λmax=660 nm) and by the use of the instrument FS-Ⅳ Flow Analyzer,ammonia (including ammonium) nitrogen in water was determined photometrically. Sensitivity accuracy and precision of the method were tested,and the values of D.L.,RSD and recovery obtained were 0.003 mg·L-1,<2% and in the range of 90%-111% respectively.