It can also be made by calcinating silica gel obtained by neutralization or decomposition of sodium silicate. Silicon dioxide can be prepared by oxidizing elemental silicon, for obtaining high purity silica. Amounts as high as 30 pounds can often be bought, or as little as one pound, for a reasonable price. Several other electronic devices that contain quartz are crystal oscillators, quartz clocks, quartz heat lamps.Ĭeramics stores often sell quite pure silicon dioxide that is already reduced to a fine powder, making this perhaps the best source to obtain it.
#Silica dioxide windows
The windows from old CPU's and EPROMs are made of fused quartz. Natural quartz crystals are a very good source of silicon dioxide, as it has few impurities (the colorless ones are purer). While each pack only contains a small amount, an opportunity such as working in a warehouse may arise where a very substantial supply of silica gel packs can be found. However, since molten sodium hydroxide is extremely dangerous to handle, this should not be attempted unless you're a professional.Ī more pure form of silicon dioxide can be found in the small packs of silica gel placed in the containers of items to absorb any moisture that may otherwise affect the product. One way to obtain pure silica from gall is to dissolve it in molten sodium hydroxide and after cooling, the resulting sodium and calcium, zinc ions from the glass are dissolved in acid, leaving behind relative pure silica, which can be purified via filtration. Powdered glass likely contains other impurities that cannot be removed through the above process. While ordinary glass is mostly silica, it also contains calcium and or sodium oxides, that are nearly impossible to remove. Relatively pure silicon dioxide can be obtained from beach sand by treating the sand with hot concentrated acid for an extended period of time, dissolving most impurities. Silicon dioxide has many allotrope forms. Silicon dioxide is a white compound, insoluble in water and acids. Molten sodium hydroxide, or any alkali hydroxide, will very quickly attack silica, meaning it must be contained in stainless steel or another medium for use in molten state. Very hot or concentrated solutions of sodium hydroxide, or any alkali hydroxide, can also dissolve and react with silicon dioxide, forming an aqueous solution of sodium silicate (waterglass). It is important to note that while silicon dioxide is largely unreactive with most substances, it is incompatible with a few very reactive chemicals, including hydrofluoric acid, which readily dissolves most kinds of glass.
0 kommentar(er)
