Word: silica
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...week this useful packaging discovery had become a prime aid in the shipment of U.S. equipment, from airplanes to bomb sights, all over the world. The process, which has big postwar possibilities, was exhibited at an ordnance show in Philadelphia. The nub of the matter is a substance called silica...
Adsorbing Gel. One of the most efficient adsorbent materials known, silica gel was first produced commercially (for use in gas masks) in World War I. It also has industrial uses as a dehydrator and catalyst. Made by drying a gelatinous form of silicon dioxide, silica gel looks like crushed quartz, is riddled with invisible pores so numerous that a cubic inch has more than 50,000 square feet of interior surface. By adsorption (sticking of moisture to the surface), silica gel can hold half its own weight in water without swelling, caking or developing a visible sweat...
Called Seaporcel, a silica product, the coating is first sprayed, then fired on the surface of metal. The Navy and Maritime Commission are covering bulkheads, doors, crews' quarters and galleys with it. It does not char, chip or crack, can be cut or tack-welded like uncoated metal, and actually strengthens light steel sheets to which it is applied-a quality which may make it possible to build lighter ships. Whether Seaporcel can be used on a ship's hull is still a moot question; the Navy is testing to see whether barnacles will grow...
...from high-grade bauxite ores. The process takes advantage of the fact that part of the aluminum silicate of which clay is largely composed is aluminum oxide. Boiling hydrochloric acid, Hixson found, combines with the oxide to form aluminum chloride dissolved in water (though it does not affect the silica). Impurities such as iron chloride (formed at the same time) are then removed with an ether. The remaining aluminum' chloride solution is then heated, aluminum is precipitated as hydrated oxide, and baking changes it to alumina ready to be electrolyzed by the Hall-Héroult process to produce...
...Optical glass made without silica (sand or quartz)-"almost as revolutionary," says Eastman Kodak Co., "as if someone had discovered how to make steel without iron." It is compounded of three rare metals: tantalum, tungsten, lanthanum...