Handling of ethylene oxide

Guidelines for Bulk Handling of Ethylene Oxide, London, CIA, 1983... 

Tests Tests shall be conducted as follows Exercise care in the handling of ethylene oxide as it is an explosive and toxic.material. Conduct all tests in a ventilated hood. Use... 

Small shipments of ethylene oxide are made in either compressed gas cylinders up to -0.1 m3 (30 gal) or in 1A1 steel drums (61 gal). Very large shipments >40 m3 (10,000—25,000 gal) are made in insulated, type 105J100W or other DOT approved tank cars. For further information on the shipping and handling of ethylene oxide, see References 9 and 227. 

Several companies have published descriptive bulletins for the safe handling of ethylene oxide, propylene oxide, and butylene oxide. Typical glassware and technical reviews are given in [5,6]. Some physical properties of ethylene and propylene oxides are given in Table I. 

Hazards attendant on use of ethylene oxide in steriliser chambers arise from difficulties in its subsequent removal by evacuation procedures, owing to its ready absorption or adsorption by the treated material. Even after 2 evacuation cycles the oxide may still be present. Safety is ensured by using the oxide diluted with up to 90% of Freon or carbon dioxide. If high concentrations of oxide are used, an inert gas purge between cycles is essential [7], The main factors in safe handling... 

Explosibility. Liquid ethylene oxide is stable to detonating agents, but the vapor will undergo explosive decomposition. Pure ethylene oxide vapor will decompose partially however, a slight dilution with air or a small increase in initial pressure provides an ideal condition for complete decomposition. Copper or other acetylide-forming metals such as silver, magpesium, and alloys of such metals should not be used to handle or store ethylene oxide because of the danger of the possible presence of acetylene. Acetylides detonate readily and will initiate explosive decomposition of ethylene oxide vapor. In the presence of certain catalysts, liquid ethylene oxide forms a poly-condensate. 

Mechanical seal of a pump handling a mixture of ethylene oxide and strong acids at 200°C (390°F) and high pressures... 

Phosphate esters are widely used in metalworking and lubricants. A C12 h with 6 mol of ethylene oxide (diester) can be used as an emulsifier but also as an extreme pressure additive - it can reduce wear where there is high pressure metal to metal contact. PEs can also show corrosion inhibiting properties, as with petroleum sulphonates and the emulsifying power of PEs with low foam is used in agrochemical formulations. PEs can act as dispersants or hydrotropes in plant protection formulations, allowing the development of easy-to-handle and dilute formulations of both poorly miscible and insoluble herbicides. 

The nature of ethylene oxide and, to a lesser degree, the higher alkylene oxides, because of their high reactivity, flammability and explosion hazards mean that plants handling these reactants must be designed to eliminate all possible ignition sources. Reactions must be operated in inert conditions and have explosion pressure rated plant design [ 1-4]. 

National Fire Protection Association, Standard for the Storage, Handling, and Use of Ethylene Oxide for Sterilization and Fumigation. NFPA 560, Quincy, MA, 1995. 

Caution Leong reports that the cyclic tetramer of ethylene oxide is acutely toxic to rats and rabbits. He suggests that all macrocychc ethers should be handled in a manner that precludes exposure until their toxicological properties have been evaluated. 

Contact with an aqueous solution of ethylene oxide on skin can produce severe bums after a delay period of a few hours. It may be absorbed by plastic, leather, and rubber materials if not handled properly, and can cause severe skin irritation. 

The objective of this paper is applying the multi-objective based analysis for the process synthesis with wastes minimization. A step-by-step systematic approach is proposed to ensure the reduction or elimination of the conflicts with regards to the waste handling and multi-objective synthesis. The pollution prevention alternatives are identified and the superstructure aimed at wastes minimization is formulated for the further mathematical optimisation. A case study, air-based direct oxidation process for the production of ethylene oxide, is presented for the illustration of the proposed approach. 

Two points should be borne in mind (i) because of the explosive nature of ethylene oxide in air, it should only be handled in a flame-free area, and the screens should be flushed with nitrogen or carbon dioxide before introducing the ethylene oxide and at the first stages of its subsequent removal (ii) rubber absorbs a certain amount of ethylene oxide and this can cause reactions in sensitive skins. This can be obviated by hanging the gauntlets in free air for an hour after flushing the screen. ... 

Imperial Chemical Ind. Ltd, Shell Chemicals UK Ltd., and Union Carbide UK Ltd., The Handling and Storage of Ethylene Oxide. CPP4, The Chemical Industries Safety Health Council of the Chemical Industries Association, London, August 1975. 

Alternatives to oxychlorination have also been proposed as part of a balanced VCM plant. In the past, many vinyl chloride manufacturers used a balanced ethylene—acetylene process for a brief period prior to the commercialization of oxychlorination technology. Addition of HCl to acetylene was used instead of ethylene oxychlorination to consume the HCl made in EDC pyrolysis. Since the 1950s, the relative costs of ethylene and acetylene have made this route economically unattractive. Another alternative is HCl oxidation to chlorine, which can subsequently be used in dkect chlorination (131). The SheU-Deacon (132), Kel-Chlor (133), and MT-Chlor (134) processes, as well as a process recently developed at the University of Southern California (135) are among the available commercial HCl oxidation technologies. Each has had very limited industrial appHcation, perhaps because the equiHbrium reaction is incomplete and the mixture of HCl, O2, CI2, and water presents very challenging separation, purification, and handling requkements. HCl oxidation does not compare favorably with oxychlorination because it also requkes twice the dkect chlorination capacity for a balanced vinyl chloride plant. Consequently, it is doubtful that it will ever displace oxychlorination in the production of vinyl chloride by the balanced ethylene process. 

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