A. Nitrate
Determination of nitrate-nitrogen used brucine method with reagents brucine and concentrated sulfuric acid. brucine reactions with nitric yellow forming compounds. the reaction speed is greatly influenced by the heat of solution. heating is done by adding a solution of concentrated sulfuric acid. Nitrate content measurement in addition to using brucine method can also use methods Cadnium Reduction Methode, Ultraviolet Spectrophotometric Screening Method or Nitrate Electrode Method.
Nitrate-Nitrogen measurement procedure with Brucine method.
Ways of working :
a. Strain 25-50 ml water sample with filter paper
b. Take a sample of 5 ml put in a beaker
c. Add 0.5 ml of brucine stir
d. Add 5 ml of concentrated H2S04 stir
e. After the muted and do spectrophotometer with wave 410 nm (log data)
f. The creation of standards, ie 5 ml NO3 taken and put in a flask, add 100 ml of distilled water sebnyak and whipped until blended. Then take 25 ml and drip with brucine 0.5, and 5 ml of H2SO4 and dispektro silenced by a wave of 410 nm.
g. For the blank, the first taken 25 ml of distilled water, then drip with brucine 0.5, and 5 ml of H2SO4. Settling and dispektro
B. Nitrite
Measurement of nitrite-nitrogen can using sulfanilamide. reagent used is sulfanilamide as diazotizing reagent and NED (N-1-napthyl-ethylene-diamine-dihydrochloride) as the coupling reagent. nitrite in the water react with the reactants forming diazonium salts together form compounds ‘azo’ bright red (pink).
Measurement procedure nitrite-nitrogen by the method of sulfanilamide
Ways of working :
a. Strain 25-50 ml water sample with filter paper
b. Pipette 10 ml of sample water that has been filtered put into the beaker
c. Add 0.2 ml (+4 drops) diazotizing reagent, stir, allow 2-4 minutes
d. Add 0.2 ml ned, stir, let stand for 10 minutes to form a red color (pink) with perfect
e. Create a blank solution of 10 ml of distilled water, perform the procedure 3 and 4
f. Create a series of standard solution of nitrite-n to the concentration (ppm) as follows: 0,025; 0.05; 0.01; 0.02; 0.04; 0.06; 0.08 of 1 ppm standard solution by dilution right by using a pipette and flask. Perform the procedure 3 and 4
g. With reference solution and at a wavelength of 543 nm, a spectrophotometer set at absorbance = 0.000, then measure the sample and the standard solution
h. To determine the concentration of nitrite-nitrogen, create charts or regression equation (y = ax + b) of laruran standard. The x-axis as the concentration (ppm) of nitrite nitrogen ddan y axis as absorbance values (a) or the transmitter (t). A value or t water samples were plotted on a graph or substituted in the regression equation, in order to obtain the levels of nitrite-nitrogen in the water.