[Study and spectrophotometric determination of nitrite with sulfanilamide and N-phenyl J-Acid system].
In the present article, compounds used in diazotizing-coupling reaction were selected. The conditions and methods of diazotizing-coupling chromogenic reaction were studied. A new method of diazotizing-coupling spectrophotometry with sulfanilamide(p-aminobenzene sulfonamide) and J-Acid series dye intermediates (N-phenyl J-Acid, J-Acid, Di-J-Acid) to determine nitrite was developed. At room temperature, in the presence of potassium bromide, nitrous acid reacted with sulfanilamide in the medium of thin hydrochloric acid. Then diazonium salt reacted with N-phenyl J-Acid in the aqueous solution of sodium carbonate, forming coloured azo compounds. The apparent molar absorptivity was 4.63 x 10(4) L x mol(-1) x cm(-1). The Beer's law was obeyed in the range of 0.003-0.7 mg x L(-1). The recoveries were in the range of 99.5%-101.6%. RSD was 2.1%. This method has been used for the determination of trace nitrite in the environmental water.
Yu
Yun
Y
College of Urban Construction, University of Shanghai for Science and Technology, Shanghai 200093, China.
Shi
Wen-jian
WJ
Yang
Ning-fei
NF
D000143:Acids / Q000737:chemistry*; D001391:Azo Compounds / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D009573:Nitrites / Q000032:analysis*; D013053:Spectrophotometry / Q000379:methods*; D000077145:Sulfanilamide; D013424:Sulfanilamides / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry*
D000143:Acids; D001391:Azo Compounds; D009573:Nitrites; D013424:Sulfanilamides; D014867:Water; D000077145:Sulfanilamide