Glass Equipment

Preparation of the polymer can be carried out in glass equipment at atmospheric pressure at temperatures typically above 100°C, but the higher pressures in an autoclave result in much faster reaction rates. Each polymer molecule which used butanol as a starter contains one hydroxyl end group as it comes from the reactor diol-started polymers contain two terminal hydroxyls. Whereas a variety of reactions can be carried out at this remaining hydroxyl to form esters, ethers, or urethanes, this is normally not done and therefore lubricant fluids contain at least one terminal hydroxyl group (36). 

These are measurements of standard ground-glass equipment. 

Pressure rupture of even a small pieee of equipment may result in a serious explosion generating missiles travelling at high veloeity. This is an important eonsideration when using laboratory glassware or industrial glass equipment and pipework. 

Maintenance of guards on machinery, open vessels, handrails, screens at sampling/ drumming-up points etc. and on glass equipment Use of sparkproof tools where appropriate Record-keeping... 

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. 

No glass equipment used for flammable or hazardous materials, unless no suitable alternative is available. 

Ground-glass equipment is preferred corks are attacked by the bromine used later. 

Etching of the glass equipment is reduced to a minimum if all equipment used in the preparation and subsequent manipulation is rinsed with water and acetone immediately after use. 

The Freon solvent may be removed under reduced pressure in order to shorten the distillation time. Since phenylsulfur trifluoride attacks glass, the total time involved in the preparation and distillation in the glass equipment should be kept to a maximum of a few hours. It is recommended that the column be changed after distillation of the Freon . If the preparation cannot be completed within a day, the Freon solution of crude phenylsulfur trifluoride may be stored in polyethylene bottles overnight. 

In contact with moisture of glass, phenylsulfur trifluoride develops pink, green, or bluish colors. A small amount of discoloration does not appear to affect the quality. Phenylsulfur trifluoride prepared in glass equipment always contains a few percent of phenylsulfinyl fluoride. The amount of this impurity depends on the care taken to exclude moisture during preparation and manipulation. 

Heavy wall tubing plain, coloured, striped tubing fabrications for instrumentation automotive push-pull cables industrial and process hydraulics and other fluids. .. Piping liners for glass-lined reactors, stainless steel reactors, glass equipment and mixers... Membranes, filter media, filter bags, cartridges, microfiltration membranes, vents and adsorbent products. .. 

Although some slight etching can take place, at this stage glass equipment is entirely safe, and no contamination of the product occurs. 

The reaction may also be performed at atmospheric pressure with ground-glass equipment if carbon monoxide saturation of the solution is maintained. However, somewhat lower yields (about 65%) result under these conditions, tAvailable from Alfa Products, Ventron Corp., P.O. Box 299, Danvers, MA 01923. 

Initially tests were conducted in glass equipment at atmospheric pressure. It was discovered that a more durable catalyst could be made if the Group VI metal oxide were deposited on an alumina support. The best support found for this reaction was alumina, and the first commercial catalyst was made by impregnating a material very similar to activated alumina 1 with a molybdenum salt solution, followed by drying and calcining at a temperature above 1000° F. Interestingly enough, the supported chromia catalyst which showed a marked superiority over the supported molybdena catalyst at atmospheric... 

Ground-glass equipment is advisable. The fractionating column is the standard modified Claisen type. 

About 550-560 ml. of tetrachloroethane is recovered. Ground-glass equipment is preferable for the distillations. 

Ground-glass equipment is preferable, since the final temperature is high enough to decompose rubber or cork stoppers. 

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