What is the significance of the determination of total organic carbon in purified water?
Purified water represents the total amount of organic matter in water by carbon content. It is an important indicator of water quality. The detection of total organic carbon in water is an important item for the detection of pharmaceutical water. Inspection item 2005 edition test item [1] character: This product is colorless and tasteless clear liquid. Check: pH, take this product 10ml, plus methyl red indicator liquid 2 drops, may not show red; another take 10ml, add bromine, thymol blue, indicating liquid 5 drops, may not show blue. Chloride, sulfate and calcium salt were taken in three test tubes, each with 50ml.
The first tube with 5 drops of nitric acid and silver nitrate solution 1ml second tube plus barium chloride solution 2ml third tube plus ammonium oxalate solution 2ml, are not allowed to turbidity. Take this product 5ml nitrate test tube, in ice bath cooling, adding 10% potassium chloride solution and 0.1% 0.4ml aniline two 0.1ml sulfuric acid solution, then slowly adding sulfuric acid 5ml, shake the tube in 50 DEG C water bath for 15 minutes, the solution with the standard blue nitrate solution [for potassium nitrate 0.163g, dissolved in water and diluted to 100ml, shake, precise amount of water into 1ml, 100ml, then the precise amount of water into 10ml, 100ml, and the (per 1ml equivalent to 1 gNO3]0.3ml), with no nitrate water 4.7ml, compared with the same method after color not more, (0.000006%). Nitrite to take this product 10ml, the Nessler tube, and sulfanilamide dilute hydrochloric acid solution (1, 100) and 1ml hydrochloride Naphthylethylenediamine (0.1 - 100) 1ml solution, the pink, and the standard solution of sodium nitrite and nitrite [0.750g (calculated on dry goods), dissolved in water, dilute to 100ml, shake, precise amount of water into 1ml, 100ml, and then precise amount of water into 1ml, 50ml, and the (equivalent to 1 gNO2 per 1ml) 0.2ml), plus nitrite free water 9.8ml, compared with the same method after color, shall not be deeper (.000002%). Take this product 50ml ammonia, alkaline potassium tetraiodomercurate solution 2ml, placed 15 minutes; such as color, with ammonium chloride solution (from ammonium chloride 31.5mg, and no amount of ammonia dissolved and diluted into 1000ml 1.5ml), compared with alkaline solution and free ammonia 48ml iodine potassium iodide solution made from 2ml, not deeper (0.00003%).
