![]() This process is known as oxychlorination. Hydrogen chloride recovered from the cracking of ethylene di-chloride is recycled in the process via reaction with oxygen and ethylene over a copper catalyst to make more ethylene dichloride. Pure, dry ethylene dichloride is thermally cracked to produce VCM and hydrogen chloride. The crude ethylene dichloride is washed, dried and purified. In the ethylene-based process, ethylene dichloride is synthesized by the reaction of elemental chlorine with ethylene over a catalyst. A less common method is by hydrochlorination of acetylene ( WHO, 1999 Cowfer & Gorensek, 2006). Over 95% of the VCM produced worldwide in 2006 was made by this method. The most common method for the production of vinyl chloride monomer (VCM) is by thermal cracking of ethylene dichloride (1,2-dichloroethane). (2000) proposed the use of a solid-phase microextraction/GS/MS to analyse vinyl chloride in materials and aqueous samples. ![]() The Department of Labor (1989) of the USA published the Occupational Safety and Health Administration method 75 that detects vinyl chloride in air with a reliable quan-titation limit of 0.020 ppm. The Environmental Protection Agency method TO-1 analyses volatile organic compounds in ambient air using Tenax ® and detection by gas chromatography (GS)–mass spectrometry (MS) method TO-14 analyses volatile organic compounds in ambient air using canister sampling followed by high-resolution GC ( Environmental Protection Agency, 1999).Ī GC analytical method has been used since 1978 to determine vinyl chloride concentrations in foodstuffs and in vinyl chloride polymers and copolymers that are intended to come into contact with food (Directive 78-142-EEC European Commission, 1978). Several methods for the analysis of vinyl chloride in ambient air have been developed. Several reviews of methods of sampling and analysis of vinyl chloride in the workplace atmosphere, ambient air, water, water piping, food and cigarette smoke, and of polyvinyl chloride (PVC) are available ( Environmental Protection Agency, 1975 Laramy, 1977 Egan et al., 1978). ![]()
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