The method describes how to determine the free and total chlorine content using a titrimetric method with DPD.
The analysis involves a reaction with N,N-diethyl-1,4-phenylenediamine (DPD), which forms a compound possessing a red color at a pH of 6.2–6.5. The solution is titrated with an ammonium iron(II) sulfate standard solution until the red color disappears. Total chlorine is measured through the addition of potassium iodide, of which a known amount in excess of that required is added to the solution in advance.
The method describes how to determine the free chlorine and total chlorine content using a photometric method with DPD.
The analysis involves a reaction with N,N-diethyl-1,4-phenylenediamine (DPD), which forms a compound possessing a red color at a pH of 6.2–6.5. The color is measured photometrically at 510 nm. Total chlorine is measured through the addition of potassium iodide, of which a known amount in excess of that required is added to the solution in advance.
The method describes how to determine the chlorine dioxide content of water photometrically with a cuvette test.