Deionized water.
Deionized water is deeply demineralized ultrapure water. It is purity of 99.99999 %. This water purified from ions impurities.
The requirements for deionized water
Deionized water:
Deionized water (deionized water) – water, purified from ions impurities. Chemical composition dionisievna water is only H2O molecules.
The main method of obtaining deionized water consists of a deep purification using reverse osmosis and subsequent deep deionization with ion exchange resins. It uses two types of resins: cationite R-H (R-organic radical) and anionite R-OH. Ions of the metal contact on the cation. Negative ions of acidic residues deposited on the anion exchanger. The resulting ions are H and OH combine in a molecule of water.
Deionized water is deeply demineralized ultrapure water. It is purity of 99.99999 %. This water has a high specific resistance, which is up to 18 Mω·cm is for the indicator (specific resistance) determine whether this water dionisievna or not.
Dionisievna water has a high chemical activity, is an excellent solvent. It is able to dissolve and absorb ions in the external environment, which adjoins:
– gas ions from the air,
– metal ions and acid residues and salts from the solid surfaces of containers, vessels, etc.
Due to the high chemical activity dionisievna water is stored in special containers made of PTFE.
Dionisievna water finds its application in electronic, chemical and food industries, in medicine and cosmetics, in engineering and agriculture, detergent and solvent. For drinking this water is unusable because it washes out of the body all the essential salts and does not bring any new.
The requirements for deionized water:
The requirements for deionized water is established in the regulations of the Russian Federation OST 11.029.003-80 and regulations of the American electronics industry ASTM D-5127-90.
Water parameters | Brand water at OST 11.029.003-80 | Grade water standards ASTM D-5127-90 |
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And | B | In | E-1 | E-2 | E-3 | E-4 | |
Specific resistance at 20 °C, Mω/cm | 18 | 10 | 1 | 18 | 17,5 | 12 | 0,5 |
The content of organic substances (biochemical oxygen demand), mg O2/l, not more | 1,0 | 1,5 | |||||
Total organic carbon, mg/l, max | 25 | 50 | 300 | 1000 | |||
The content of silicic acid (calculated as SiO3-2), mg/l, max | 0,01 | 0,05 | 0,2 | 0,005 | 0,01 | 0,05 | 1,0 |
The contents iron, mg/l, max | 0,015 | 0,02 | 0,03 | ||||
The content of copper, mg/l, max | 0,005 | 0,001 | 0,002 | 0,5 | |||
The contents of micro-particles with size of 1-5 µm, PC/l not more than | 20 | 50 | not regulated | ||||
The content of microorganisms, colonies/ml, no more | 2 | 8 | not regulated | ||||
Chlorides, mg/l, max | 1 | 10 | 1000 | ||||
Nickel, µg/l, not more | 0,1 | 1 | 2 | 500 | |||
Nitrates, mg/l, max | 1 | 5 | 500 | ||||
Phosphates, mg/l, max | 1 | 5 | 500 | ||||
Sulfates, mg/l, max | 1 | 5 | 500 | ||||
Potassium, mg/l, max | 2 | 5 | 500 | ||||
Sodium, mg/l, max | 0,5 | 1 | 5 | 500 | |||
Zinc, µg/l, not more | 0,5 | 1 | 5 | 500 |
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