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Redirect from ethylene chloride

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If you search on ethylene chloride, you end up on the vinyl chloride page. Traditionally the term, ethylene chloride has referred to 1,2 dichloro ethane. There should be at least a disambiguation page for this. Karl Hahn (T) (C) 17:44, 19 March 2007 (UTC)[reply]

Karl, Britannica Online Encyclopedia shows the definition you cite.[1] However, the term ethylene dichoride (EDC) is much more widely used for 1,2 dichloroethane. I had not seen ethylene chloride used to mean vinyl chloride, though I have seen chloroethene used in some scientific articles. ChemE50 (talk) 17:25, 27 August 2009 (UTC)[reply]

Lack of Referencing

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There's a lack of Referencing under subheads of Vinyl chloride monomer and Dioxin. They seem to have footnotes but they aren't referenced. —Preceding unsigned comment added by 99.230.45.10 (talk) 20:46, 16 November 2008 (UTC)[reply]

See the section below for an explanation: I'll now bring over the refs from the original article. Gonzonoir (talk) 09:49, 28 June 2009 (UTC)[reply]

Contents merged in from Polyvinyl chloride

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A year ago, with this edit, an IP copied a section from Polyvinyl chloride into this article. The move wasn't attributed at the time; please see the page history of Polyvinyl chloride for contributor attribution. Gonzonoir (talk) 09:47, 28 June 2009 (UTC)[reply]

Health Effects

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The subsection on dioxins should be moved to the Dioxin (chemical) page. The text primarily discusses health effects of dioxins generated by burning PVC. Dioxin generation is more closely linked to PVC production and use than to VCM production.ChemE50 (talk) 23:48, 27 August 2009 (UTC)[reply]

In the UK VCM is not classified as toxic or very toxic - source CHIP approved supply list 2005. It is labelled as toxic because it is a carcinogen. There is no classification of "highly toxic." — Preceding unsigned comment added by 88.96.247.172 (talk) 10:38, 15 December 2011 (UTC)[reply]

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"Ethane sulfochlorination has been proposed as a route to produce vinyl chloride using sulfur instead of oxygen" suggests a direct analogy to the oxychlorination process but with sulphur instead of oxygen. However, this link, in the other processes routes, is redirected to the Reed reaction, using sulphur dioxide, chlorine and a photochemical process to form sulphonyl chloride groups on alkanes, i.e. not chlorosubsituted alkenes. One sample product is called chlorosulfonated polyethylene (CSPE). It seems that the two terms sulfochlorination and chlorosulfonation are distinct from each other but have been mixed up. One culprit seems to be the redirection and possibly a missing proper sulphochlorination article. The product name "chlorosulfonated polyethylene" also contributes to the mess. It would be nice if somebody could state what the correct nomenclature is but even if "chlorosulfonated polyethylene" is incorrect it may be established and then some explanation and disambiguition of the concept "sulphochlorination" is needed. I don't know how to change the redirection but will unlink the sulfochlorination link.150.227.15.253 (talk) 09:57, 13 June 2022 (UTC)[reply]

I removed that remark. It is based on one sentence in the Ullmann encyclopedia, supported by this patent: Seymour C. Schuman, US 3 377 396, 1968. Otherwise, a search of ChemAbs seems to indicate that sulfochlorination involves the addition of Cl-SO2R across double bonds, as illustrated with this recent paper: "Fast Heating-Assisted One-Pot Copper-Catalyzed Sulfonylation and Sulfochlorination of Styrenes" Jorge Saavedra-Olavarría, Patricio Hermosilla-Ibáñez, Iriux Almodóvar, Edwin G. Pérez in Eur. J. Org. Chem. doi.org/10.1002/ejoc.202101526.--Smokefoot (talk) 20:47, 13 June 2022 (UTC)[reply]

Uncited material in need of citations

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I am moving the following uncited material here until it can be properly supported with inline citations of reliable, secondary sources, per WP:V, WP:NOR, WP:CS, WP:NOR, WP:IRS, WP:PSTS, et al. This diff shows where it was in the article. Nightscream (talk) 14:24, 30 July 2022 (UTC)[reply]

Extended content

Uses

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Vinyl chloride is a chemical intermediate, not a final product. Due to the hazardous nature of vinyl chloride to human health there are no end products that use vinyl chloride in its monomer form. Polyvinyl chloride (PVC) is very stable, storable, and not toxic as the vinyl chloride monomer (VCM).[citation needed]

Vinyl chloride liquid is fed to polymerization reactors where it is converted from a monomeric VCM to a polymeric PVC. The final product of the polymerization process is PVC in either a flake or pellet form. From its flake or pellet form PVC is sold to companies that heat and mold the PVC into end products such as PVC pipe and bottles. Several million tons of PVC are sold on the global market each year.[citation needed]

Production

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In 1912, Fritz Klatte, a German chemist working for Griesheim-Elektron, patented a means to produce vinyl chloride from acetylene and hydrogen chloride using mercuric chloride as a catalyst. This method was widely used during the 1930s and 1940s in the West. It has since been superseded by more economical processes based on ethylene in the United States and Europe. The mercury-based technology is the main production method in China.[citation needed]

Thermal decomposition of dichloroethane

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1,2-Dichloroethane, ClCH2CH2Cl (also known as ethylene dichloride, EDC), can be prepared by halogenation of ethane or ethylene, inexpensive starting materials. When EDC in gas phase is heated to 500 °C at 15–30 atm (1.5 to 3 MPa) pressure, it decomposes to produce vinyl chloride and anhydrous HCl. This production method is cheaper than preparing EDC from acetylene, which is why it has become the major route to vinyl chloride since the late 1950s.[citation needed]

ClCH2CH2Cl → CH2=CHCl + HCl

The thermal cracking reaction is highly endothermic, and is generally carried out in a fired heater. Even though residence time and temperature are carefully controlled, it produces significant quantities of chlorinated hydrocarbon side products. In practice, the yield for EDC conversion is relatively low (50 to 60 percent). The furnace effluent is immediately quenched with cold EDC to stop undesirable side reactions. The resulting vapor-liquid mixture then goes to a purification system. Some processes use an absorber-stripper system to separate HCl from the chlorinated hydrocarbons, while other processes use a refrigerated continuous distillation system.[citation needed]

Production from acetylene

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Acetylene reacts with anhydrous hydrogen chloride gas over a mercuric chloride catalyst to give vinyl chloride:

C2H2 + HCl → CH2=CHCl. The reaction is exothermic and highly selective. Product purity and yields are generally very high.[citation needed]

Production from ethane

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High-temperature chlorination:

C2H6 + 2 Cl2 → C2H3Cl + 3 HCl

High-temperature oxychlorination:

C2H6 + HCl + O2 → C2H3Cl + 2 H2O

High-temperature oxidative chlorination:

2 C2H6 + 32 O2 + Cl2 → 2 C2H3Cl + 3 H2O

A major drawback to the use of ethane are the forcing conditions required for its use, which can be attributed to its lack of molecular functionality. In contrast to ethylene, which easily undergoes chlorine addition, ethane must first be functionalized by substitution reactions, which gives rise to a variety of consecutive and side-chain reactions. The reaction must, therefore, be kinetically controlled in order to obtain a maximal vinyl chloride yield. Vinyl chloride yields average 20–50% per pass. Ethylene, ethyl chloride, and 1,2-dichloroethane are obtained as major byproducts. With special catalysts and at optimized conditions, however, ethane conversions of greater than 96% have been reported from oxychlorination reactions. The ethylene formed can either be recycled or oxychlorinated and cracked in a conventional manner. Many such ethane-based processes have been and are being developed.[citation needed]

Other routes

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Vinyl chloride can also be obtained as a byproduct in the synthesis of chlorofluorocarbons when saturated chlorofluorocarbons are catalytically dechlorinated by ethylene.[citation needed]

Fire and explosion hazard

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Vinyl chloride is a gas at normal atmospheric temperature and pressure.[citation needed]

It is flammable, and emits hydrogen chloride.[citation needed]

Health effects

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The US OSHA limits vinyl chloride exposure of workers to no more than 1 ppm for eight hours or 5 ppm for 15 minutes. The US Environmental Protection Agency (EPA) and FDA limit vinyl chloride in drinking water to 0.002 ppm. Food (ingestion) is a trivial source of exposure.[citation needed]

Cancerous tumors

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In the late 1960s, the cancers that all of these studies warned of finally manifested themselves in workers. John Creech from B.F. Goodrich discovered angiosarcoma (a very rare cancer) in the liver of a worker at the B.F. Goodrich plant in Louisville, Kentucky. Then, finally, on January 23, 1974, B.F. Goodrich informed the government and issued a press release stating that it was "investigating whether the cancer deaths of three employees in the polyvinyl chloride operations at its Louisville, Ky. plant were related to occupational causes."[citation needed]

EPA

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The article cites "EPA", without stating what EPA it stands for. One can guest it is some official controlling body from the context, but people like me have no idea if it's some local organization or a UN agency. 85.195.209.11 (talk) 12:51, 15 February 2023 (UTC)[reply]

Conflicting vital information

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Article lede states "About 13 million tonnes are produced annually."

But in the Production section, it states "Approximately 31.1 million tons were produced in 2000."

This difference hurts the credibility of the article.

More scrutable and well-known reference sources would help in resolving this huge discrepency. (Some major encyclopedias e.g. EB, don't attempt this number.) In the meantime, I'm removing both statements. Twang (talk) 21:09, 17 February 2023 (UTC)[reply]