2,6-二甲酚双波长分光光度法同时测定水中NO_(3)^(-)及NO_(2)^(-)的研究

Dual-Wavelength Spectrophotometric Determination of Nitrate and Nitrite with 2,6-Xvlenol

水中NO_(3)^(-)和NO_(2)^(-)的一般光度法同时测定已见报导,但其操作手续均较麻烦。2,6-二甲酚光度法单独测定NO_(2)^(-)或NO_(2)^(-)虽已有报导,可是它们相互干扰。我们采用双波长光度法,测定NO_(3)^(-)和NO_(2)^(-)在H_(2)SO_(4)介质与2,6-二甲酚的反应产物,既免除了它们的相互干扰,又达到同时测定的目的。

Nitrate and nitrite react with 2,6-xylenol in H2SO4solution.On the basis of this fact we simutaneously determined nitrate and nitrite with dual-wavelength at 318nm-290.5nm and 305.5nm-332.5nm.Beer's law is obeyed in the range 0.00-19.03μg NO3--N/25ml and 0.00-12.00μg NO2--N/25ml and△ε318;390.5nm is 2.3×103and△ε305,332.5nm is 4.74×103.After neutralization of solution with NaOH,spectra took place bathochromic shift and nitrate and nitrite can be determined with dual-wavelength at 417.5nm-359nm and 384nm-463.5nm.Beer's law is obeyed in the range 0.00-7.61μg NO3--N/25ml and 0.00-4.8μg NO3--N/25ml and△ε417.5,359nm is 1.13×104and△ε384,463.5nm is 1.29×104This methed was applied to determine of nitrate and nitrite in water.