Liquid oxygen, production

Contaminants in Liquid Oxygen as Related to Safety in Liquid Oxygen Production and Distribution Equipment (3) 218 Pressurized Transfer of Cryogenic Liquids (4) 342... 

Argon, nitrogen, carbon dioxide, methane and its homologs, nitrous oxide, and sometimes traces of other materials are residual in commercial liquid oxygen from the atmosphere in varying amounts. Since reciprocating air compressors are usually used in the liquid-oxygen production cycle, there may also be traces of thermal decomposition products of the cylinder lubricant used. 

Linde process A high-pressure process for the production of liquid oxygen and nitrogen by compression to about 200 bar (20MN/m ) followed by refrigeration and fractionation in a double column. 

Preliminary minimum distances Liquid oxygen Liquefied flammable gases Liquids stored at ambient temperature and pressure A Code of Practice for the Bulk Storage of Liquid Oxygen at Production Sites (HSE, 1977) Process Plant Layout page 562 (Mecklenburgh, 1985) Process Plant Layout page 564... 

First production of liquid oxygen on a technical scale (C. von Linde). 

A Code of Practice for the Bulk Storage of Liquid Oxygen at Production Sites (HSE, 1977)... 

Approximately 10 million pounds of trichloroethylene are used aimually as a chain transfer agent in the production of polyvinyl chloride (McNeill 1979). Other chemical intermediate uses of trichloroethylene include production of pharmaceuticals, polychlorinated aliphatics, flame retardant chemicals, and insecticides (Mannsville 1992 Windholz 1983). Trichloroethylene is used as a refrigerant for low-temperature heat transfer (Cooper and Hickman 1982 lARC 1979 McNeill 1979) and in the aerospace industry for flushing liquid oxygen (Hawley 1981 Kuney 1986). 

Iron (II) oxide and especially that made by reducing the other oxides, combusts spontaneously if it is heated to 200°C. It also strongly catalyses the combustion of carbon in air. This behaviour can explain the spontaneous inflammable property of the products of burning iron oxalate, which contain this oxide and carbon. When they are placed on the hand and thrown into the air, they form very spectacular showers of sparks. It combusts in contact with liquid oxygen in the presence of carbon. 

Procedures relevant to safe handling and use are discussed. Perchloryl fluoride is stable to heat, shock and moisture, but is a powerful oxidiser comparable with liquid oxygen. It fonns flammable and/or explosive mixtures with combustible gases and vapours [1,2]. It only reacts with strongly nucleophilic centres, and the by-product, chloric acid is dangerously explosive in admixture with organic compounds [3], Safety aspects of practical use of perchloryl fluoride have been reviewed [4],... 

The ideal systems for these media are those which do not require any additional solvent, and in which the substrate is more soluble than the product, leading to preferential rejection of the product from the catalyst phase. For fluorous reactions, this would include oxidation reactions where oxygenated products are typically more polar than the substrates. In ionic liquids it is products less polar than the substrates that will normally be less soluble, although the ability to tune the structure of ionic liquids to match a particular application must... 

Xenon is recovered from air by liquefaction and fractional distillation. Usually it is obtained as a by-product of making other noble gases. It is collected in the liquid oxygen fraction along with krypton, acetylene, and other hydrocarbons that may be present in air. The xenon fraction is flash vaporized. Hydrocarbons present are separated by burning over a catalyst. Xenon is absorbed on silica gel at low temperatures. Finally, it is separated from krypton by selective absorption and desorption from charcoal. 

In the present commercial Sasol operations the tailgas leaving the reactors are cooled to ambient temperature and the liquid products separated into two phases, namely an oil and a water phase. The lower molecular weight oxygenated products are predominantly present in the water phase. Typical compositions of these oxygenates compounds are given in Table IV. 

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