KSKG, KSMG silica gel, indicator

Silica gel represents the dried-up gel which is formed of the oversaturated solutions of silicon acids (nSiO2 · mH2O) at pH> 5 — 6. Firm hydrophilic sorbent.

Commodity silica gel is let out in the form of grains or spherical granules from 5 — 7 to 0,01 mm in size. Different brands of silica gels have the average effective diameter of time 20 — 150Å and specific surface of 102 — 103 m ²/g.

Silica gels find the main application when drying air, carbon dioxide gas, hydrogen, oxygen, nitrogen, chlorine and other industrial gases.

Ability of silica gel to absorb significant amount of water is used for drying of different liquids, in particular in that case when the dehydrated liquid badly dissolves water (drying of the halogenated liquids like freon). Silica gels serve also as dehumidifiers at preservation of the equipment for its protection from corrosion.

Along with water silica gels well occlude vapors of many organic substances. Use this its property for catching (recuperation) of vapors of gasoline, benzene, ether, acetone, etc. from air, benzene, from gas coke furnaces and gasoline from natural gases.

Property of silica gel to absorb many substances from liquid phase is used in industrial purification of different oils, at desulphuration of petroleum cuts and removals from oil of high-polymer resinous substances.

Also silica gel is used as adsorbent in chromatography as absorber of water vapors (dehumidifier) and organic solvents (for example, in dehumidifiers of compressed air, the adsorptive purification of unpolar liquids; for division of alcohols, amino acids, vitamins, antibiotics, etc.). Krupnoporisty silica gels are applied as carriers of catalysts. Also silica gel well adsorbs radon-222 kernels (and its isotopes). Silica gel is widely used for production of fillers for cat's toilets