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Natural water usually contains five kinds of impurities:
♦ Electrolytes, including charged particles, common cations are H+, Na+, K+, NH4+, Mg2+, Ca2+, Fe3+, Cu2+, Mn2+, Al3+, etc.; anions include F-, Cl-, NO3-, HCO3-, SO42- , PO43-, H2PO4-, HSiO3-, etc.;
♦ Organic substances, such as: organic acids, pesticides, hydrocarbons, alcohols and esters, etc.;
♦ Particulate matter;
♦ Microorganisms;
♦ Dissolved gases, including: N2, O2, Cl2, H2S, CO, CO2, CH4, etc.
The so-called purification of water is to remove these impurities. The more thoroughly the impurities are removed, the purer the water will be.
► Distilled water
Distilled water is water that is distilled and condensed. The second steam is called double-distilled water, and the third steam is called three-distilled water. Sometimes for special purposes, appropriate reagents are added before steaming. For example, for ammonia-free water, acid is added to the water; for water with low oxygen consumption, potassium permanganate and acid are added. Industrial distilled water is pure water obtained by the distilled water method. Generally, the purity of water obtained by ordinary distillation is not high. After multi-stage distilled water, the effluent can be very pure and the cost is relatively high.
► Deionized water
Deionized water is to pass water through a cation exchange resin (usually styrene-type strong acid cation exchange resin), the cations in the water are absorbed by the resin, and the cations H+ on the resin are replaced into the water and correspond to the cation composition in the water Inorganic acid; water containing this inorganic acid is replaced by anion exchange resin (usually styrene-type strong basic anion) OH- into the water, and combines with the H+ in the water to form water, which is deionized water. Deionized water has a very wide range of uses in modern industries. The use of deionized water is one of the important means for many industries to improve product quality and catch up with the world's advanced level. Since the number of ions in deionized water can be controlled artificially, its electrical resistivity, solubility, corrosivity, virus and bacteria and other physical, chemical and pathological indicators are well controlled. In industrial production and laboratory experiments, if deionized water is used in processes involving the use of water, many parameters will be closer to the design or ideal data, and product quality will become easier to control.
► High purity water
High-purity water refers to water with extremely high chemical purity. It is mainly used in the fields of biology, chemistry and chemical engineering, metallurgy, aerospace, electric power, etc. However, it requires high water purity, so it is generally used in the electronics industry. For example, the pure water used in the power system requires the content of each impurity to be as low as "micrograms/liter". In the production of pure water, the various indicators specified in the water quality standards should be determined according to the production process of electronic (microelectronic) components (or materials) (for example, the size of the particulate matter that is generally believed to cause circuit performance damage is its line width 1/5-1/10), but due to the complexity of microelectronics technology and many factors that affect product quality, there is still no complete water quality standard that can be obtained from process tests and is suitable for a certain circuit production. However, in recent years, electronic water standards have also been continuously revised, and many breakthroughs and developments in the field of high-purity water analysis, and the continuous application of new instruments and new analytical methods have created conditions for the development of water production processes.
► Ultra-pure water
Ultra-pure water can be considered to be a degree that is difficult to achieve in general processes. If the resistivity of water is greater than 18MΩ*cm (without obvious boundaries), it is called ultra-pure water. The key is to look at the purity of your water and various characteristic indicators, such as conductivity or resistivity, PH value, sodium, heavy metals, silica, dissolved organic matter, particulates, and microbial indicators.
VOLARDDA can produce different specifications of deionized industrial ultrapure water equipment according to the specific requirements of customers for water quality, and the resistance can reach 18.2 megaohms. For details, please consult customer service staff.
