Metals glass-lined

Shell and trays The tower may be made of any number of materials, depending upon the corrosion conditions expected. Glass, glass-lined metal, impervious carbon, plastics, even wood but most frequently metals are used. For metal towers, the shells are usually cylindrical for reasons of cost. In order to facilitate cleaning, small-diameter towers are fitted with hand holes, large towers with manways about every tenth tray [66]. 

These may be of wood, metal, chemical stoneware, acidproof brick, glass, plastic, plastic- or glass-lined metal, or other material depending upon the corrosion conditions. For ease of construction and strength they are usually circular in cross section. 

Piping materials used in ohmic heaters must be nonconductive. Many forms of plastics and glass-lined metal have been successfully used in ohmic heating applications. 

Processes that are essentially modifications of laboratory methods and that allow operation on a larger scale are used for commercial preparation of vinyhdene chloride polymers. The intended use dictates the polymer characteristics and, to some extent, the method of manufacture. Emulsion polymerization and suspension polymerization are the preferred industrial processes. Either process is carried out in a closed, stirred reactor, which should be glass-lined and jacketed for heating and cooling. The reactor must be purged of oxygen, and the water and monomer must be free of metallic impurities to prevent an adverse effect on the thermal stabiUty of the polymer. 

Most metals, concrete, and other constmction materials are corroded by hydrobromic acid. Suitable materials of constmction include some fiber glass-reinforced plastics, some chemically resistant mbbers, PVC, Teflon, polypropylene, and ceramic-, mbber-, and glass-lined steel. Metals that are used include HasteUoy B, HasteUoy C, tantalum, and titanium. The HasteUoys can only be used at ambient temperatures. Liquid hydrogen bromide under pressure in glass at or above room temperature can attack the glass resulting in unexpected shattering. 

In commercial practice, chlorination may be carried out either in batches or continuously. Glass-lined or nickel reactors may be used. Because certain metallic impurities such as iron catalyze ring chlorination and self-condensation, their presence must be avoided. The cmde product is purged of dissolved... 

Chlorosulfuric acid attacks brass, bronze, lead, and most other nonferrous metals. From a corrosion standpoint, carbon steel and cast Hon are acceptable below 35°C provided color and Hon content is not a concern. Stainless steels (300-series) and certain aluminum alloys are acceptable materials of constmction, as is HasteUoy. Glass, glass-lined steel, or Teflon-lined piping and equipment are the preferred materials at elevated temperatures and/or high velocities or where trace Hon contamination is a problem, such as in the synthetic detergent industry. 

Commercial ethyl alcohol is shipped in railroad tank cars, tank tmcks, 208-L (55-gal) and 19-L (5-gal) dmms, and in smaller glass or metal containers having capacities of 0.473 L (one pint), 0.946 L (one quart), 3.785 L (one U.S. gal), or 4.545 L (one Imperial gal). The 208-L dmms may be of the unlined iron type. If a guarantee of more meticulous quaUty is desired, the dmms may be lined with phenoHc resin. AH containers, of course, must comply with the specifications of the U.S. Department of Transportation. Both 190 proof and 200 proof ethyl alcohol are considered red label (flammable) materials by the DOT, as both have flash points below 37.8°C by the Tag closed-cup method. 

Copper or glass-lined equipment for carbonyl in the presence of carbon monoxide Most common metals for dry gas. For moist gas use 18 8 stainless steel, PTFE Any common metal Most common metals for dry gas. For moist gas use 18 8 stainless steel Nickel and Monel are preferred. Steel, copper and glass are acceptable at ordinary temperatures Steel for dry gas otherwise use 18 8 stainless steel Nickel, Monel and Inconel. For moist gas tantalum is suitable Most common metals Cast iron and stainless steel <120°C, steel <175°C, Inconel, nickel and platinum <400°C Most common metals... 

All glass-lined steel tanks have at least one anode. This is a long metal rod made of magnesium, alu-... 

In the chemical process industry molybdenum has found use as washers and bolts to patch glass-lined vessels used in sulphuric acid and acid environments where nascent hydrogen is produced. Molybdenum thermocouples and valves have also been used in sulphuric acid applications, and molybdenum alloys have been used as reactor linings in plant used for the production of n-butyl chloride by reactions involving hydrochloric and sulphuric acids at temperatures in excess of 170°C. Miscellaneous applications where molybdenum has been used include the liquid phase Zircex hydrochlorination process, the Van Arkel Iodide process for zirconium production and the Metal Hydrides process for the production of super-pure thorium from thorium iodide. 

The principal advantages of glass linings are the increased size and mechanical strength that are possible compared with all-glass equipment, and the flexibility of operation with different chemicals compared with all-metal equipment. The increased heat transmission, in comparison with glass equipment, can also be an advantage. 

Most common metals Common metals for dry gas. Monel, tantalum or glass lined equipment for moist gas... 

Inconel <65°C. Glass-lined equipment. Iron and steel at ordinary temperatures C T Common metals for dry gas. 

Jacketed tank reactors, mainly stainless steel reactors and glass-lined reactors equipped with a stirrer, predominate in plants for the manufacture of fine chemicals. Glass-lined reactors are in common use although they are by 30-50 % more expensive than stainless steel reactors. This is because of the high chemical resistance of enamels towards typical chemical media and the much lower possibility of contamination of products with heavy metals, which should not be... 

The corrosion resistance of tantalum is similar to that of glass, and it has been called a metallic glass. It is expensive, about five times that of stainless steel, and is used for special applications, where glass or a glass lining would not be suitable. Tantalum plugs are used to repair glass-lined equipment. 

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