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44-478: Perfluorosulfonic acids are organofluoroanalogues of conventional alkanesulfonic acids , but they are several pK A units stronger (and are therefore strong acids ). Their perfluoroalkyl chain has a highly hydrophobic character . Perfluorooctanesulfonic acid , for example, has been used in hard chromium plating . Since the early 2000's 6:2 fluorotelomersulfonic acid has been used as a replacement for perfluorooctanesulfonic acid . Perfluorooctanesulfonic acid

88-531: A values of −2.8 and −1.9, respectively, while those of benzoic acid and acetic acid are 4.20 and 4.76, respectively. However, as a consequence of their strong acidity, their p K a values cannot be measured directly, and values commonly quoted should be regarded as indirect estimates with significant uncertainties. For instance, various sources have reported the p K a of methanesulfonic acid to be as high as −0.6 or as low as −6.5. Sulfonic acids are known to react with solid sodium chloride ( salt ) to form

132-409: A lot on the source of energy (for example gas burnt to provide high temperatures ) but that from naptha is certainly more per kg of feedstock. Both steam cracking and production from natural gas via ethane are estimated to emit 1.8 to 2kg of CO2 per kg ethylene produced, totalling over 260 million tonnes a year. This is more than all other manufactured chemicals except cement and ammonia. According to

176-530: A mixture of sulfur dioxide and oxygen . This reaction is employed industrially to produce alkyl sulfonic acids, which are used as surfactants . Direct reaction of alkanes with sulfur trioxide is not generally useful, except for the conversion methanesulfonic acid to methanedisulfonic acid . Many alkane sulfonic acids can be obtained by the addition of bisulfite to terminal alkenes. Bisulfite can also be alkylated by alkyl halides : Sulfonic acids can be prepared by oxidation of thiols : This pathway

220-442: A niche use is as an anesthetic agent (in an 85% ethylene/15% oxygen ratio). Another use is as a welding gas. It is also used as a refrigerant gas for low temperature applications under the name R-1150. Global ethylene production was 107 million tonnes in 2005, 109 million tonnes in 2006, 138 million tonnes in 2010, and 141 million tonnes in 2011. By 2013, ethylene was produced by at least 117 companies in 32 countries. To meet

264-536: A precursor to propionic acid and n-propyl alcohol . Ethylene has long represented the major nonfermentative precursor to ethanol . The original method entailed its conversion to diethyl sulfate , followed by hydrolysis. The main method practiced since the mid-1990s is the direct hydration of ethylene catalyzed by solid acid catalysts : Ethylene is dimerized by hydrovinylation to give n -butenes using processes licensed by Lummus or IFP . The Lummus process produces mixed n -butenes (primarily 2-butenes ) while

308-425: A water-solubilizing protecting group, as illustrated by the purification of para-xylene via its sulfonic acid derivative. In the synthesis of 2,6-dichlorophenol , phenol is converted to its 4-sulfonic acid derivative, which then selectively chlorinates at the positions flanking the phenol. Hydrolysis releases the sulfonic acid group. Sulfonic acids can be converted to esters . This class of organic compounds has

352-416: Is also an important natural plant hormone and is used in agriculture to induce ripening of fruits . The hydrate of ethylene is ethanol . This hydrocarbon has four hydrogen atoms bound to a pair of carbon atoms that are connected by a double bond . All six atoms that comprise ethylene are coplanar . The H-C-H angle is 117.4°, close to the 120° for ideal sp² hybridized carbon. The molecule

396-480: Is also relatively weak: rotation about the C-C bond is a very low energy process that requires breaking the π-bond by supplying heat at 50 °C. The π-bond in the ethylene molecule is responsible for its useful reactivity. The double bond is a region of high electron density , thus it is susceptible to attack by electrophiles . Many reactions of ethylene are catalyzed by transition metals, which bind transiently to

440-589: Is an organic alkyl or aryl group and the S(=O) 2 (OH) group a sulfonyl hydroxide. As a substituent, it is known as a sulfo group . A sulfonic acid can be thought of as sulfuric acid with one hydroxyl group replaced by an organic substituent . The parent compound (with the organic substituent replaced by hydrogen) is the parent sulfonic acid, HS(=O) 2 (OH) , a tautomer of sulfurous acid , S(=O)(OH) 2 . Salts or esters of sulfonic acids are called sulfonates . Aryl sulfonic acids are produced by

484-400: Is illustrated by the prototype, methanesulfonic acid . The sulfonic acid group, RSO 2 OH features a tetrahedral sulfur centre, meaning that sulfur is at the center of four atoms: three oxygens and one carbon. The overall geometry of the sulfur centre is reminiscent of the shape of sulfuric acid . Both alkyl and aryl sulfonic acids are known, most large-scale applications are associated with

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528-401: Is primarily used to make films in packaging , carrier bags and trash liners . Linear alpha-olefins , produced by oligomerization (formation of short-chain molecules) are used as precursors , detergents , plasticisers , synthetic lubricants , additives, and also as co-monomers in the production of polyethylenes. Ethylene is oxidized to produce ethylene oxide , a key raw material in

572-412: Is rarely synthesized in the laboratory and is ordinarily purchased. It can be produced via dehydration of ethanol with sulfuric acid or in the gas phase with aluminium oxide or activated alumina . Ethylene is produced from methionine in nature. The immediate precursor is 1-aminocyclopropane-1-carboxylic acid . Ethylene is a fundamental ligand in transition metal alkene complexes . One of

616-503: Is the basis of the biosynthesis of taurine . Many sulfonic acids are prepared by hydrolysis of sulfonyl halides and related precursors. Thus, perfluorooctanesulfonic acid is prepared by hydrolysis of the sulfonyl fluoride, which in turn is generated by the electrofluorination of octanesulfonic acid. Similarly the sulfonyl chloride derived from polyethylene is hydrolyzed to the sulfonic acid. These sulfonyl chlorides are produced by free-radical reactions of chlorine, sulfur dioxide, and

660-494: Is the feedstock, ethylene is the product. Ethylene is separated from the resulting mixture by repeated compression and distillation . In Europe and Asia, ethylene is obtained mainly from cracking naphtha, gasoil and condensates with the coproduction of propylene, C4 olefins and aromatics (pyrolysis gasoline). Other technologies employed for the production of ethylene include Fischer-Tropsch synthesis and methanol-to-olefins (MTO). Although of great value industrially, ethylene

704-429: Is used as catalysts and for ion exchange ( water softening ). Nafion , a fluorinated polymeric sulfonic acid is a component of proton exchange membranes in fuel cells . Sulfa drugs , a class of antibacterials, are produced from sulfonic acids. In the sulfite process for paper-making, lignin is removed from the lignocellulose by treating wood chips with solutions of sulfite and bisulfite ions. These reagents cleave

748-474: Is widely used in the chemical industry, and its worldwide production (over 150 million tonnes in 2016 ) exceeds that of any other organic compound . Much of this production goes toward creating polythene , which is a widely used plastic containing polymer chains of ethylene units in various chain lengths. Production emits greenhouse gases , including methane from feedstock production and carbon dioxide from any non- sustainable energy used. Ethylene

792-463: The Dutch oil , 1,2-dichloroethane ; this discovery gave ethylene the name used for it at that time, olefiant gas (oil-making gas.) The term olefiant gas is in turn the etymological origin of the modern word "olefin", the class of hydrocarbons in which ethylene is the first member. In the mid-19th century, the suffix -ene (an Ancient Greek root added to the end of female names meaning "daughter of")

836-466: The United States and Europe , approximately 90% of ethylene is used to produce ethylene oxide , ethylene dichloride , ethylbenzene and polyethylene . Most of the reactions with ethylene are electrophilic addition . Polyethylene production uses more than half of the world's ethylene supply. Polyethylene, also called polyethene and polythene , is the world's most widely used plastic. It

880-506: The alkylation with ethylene is ethylbenzene , precursor to styrene . Styrene is used principally in polystyrene for packaging and insulation, as well as in styrene-butadiene rubber for tires and footwear. On a smaller scale, ethyltoluene , ethylanilines, 1,4-hexadiene, and aluminium alkyls. Products of these intermediates include polystyrene , unsaturated polyesters and ethylene-propylene terpolymers . The hydroformylation (oxo reaction) of ethylene results in propionaldehyde ,

924-683: The anthraquinone dyes are produced or processed via sulfonation. Sulfonic acids tend to bind tightly to proteins and carbohydrates . Most "washable" dyes are sulfonic acids (or have the functional sulfonyl group in them) for this reason. p-Cresidinesulfonic acid is used to make food dyes. Being strong acids, sulfonic acids are also used as catalysts . The simplest examples are methanesulfonic acid , CH 3 SO 2 OH and p -toluenesulfonic acid , which are regularly used in organic chemistry as acids that are lipophilic (soluble in organic solvents). Polymeric sulfonic acids are also useful. Dowex resin are sulfonic acid derivatives of polystyrene and

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968-559: The (aryl)C−SO 3 bond can be broken by nucleophilic reagents. Of historic and continuing significance is the α-sulfonation of anthroquinone followed by displacement of the sulfonate group by other nucleophiles, which cannot be installed directly. An early method for producing phenol involved the base hydrolysis of sodium benzenesulfonate , which can be generated readily from benzene. The conditions for this reaction are harsh, however, requiring 'fused alkali' or molten sodium hydroxide at 350 °C for benzenesulfonic acid itself. Unlike

1012-510: The IFP process produces 1-butene . 1-Butene is used as a comonomer in the production of certain kinds of polyethylene . Ethylene is a hormone that affects the ripening and flowering of many plants. It is widely used to control freshness in horticulture and fruits . The scrubbing of naturally occurring ethylene delays ripening. Adsorption of ethylene by nets coated in titanium dioxide gel has also been shown to be effective. An example of

1056-588: The aromatic derivatives. Detergents and surfactants are molecules that combine highly nonpolar and highly polar groups. Traditionally, soaps are the popular surfactants, being derived from fatty acids . Since the mid-20th century, the usage of sulfonic acids has surpassed soap in advanced societies. For example, an estimated 2 billion kilograms of alkylbenzenesulfonates are produced annually for diverse purposes. Lignin sulfonates, produced by sulfonation of lignin are components of drilling fluids and additives in certain kinds of concrete . Many if not most of

1100-427: The bonds between the cellulose and lignin components and especially within the lignin itself. The lignin is converted to lignosulfonates , useful ionomers , which are soluble and can be separated from the cellulose fibers. The reactivity of the sulfonic acid group is so extensive that it is difficult to summarize. When treated with strong base, benzenesulfonic acid derivatives convert to phenols. In this case

1144-416: The ethylene using both the π and π* orbitals. Being a simple molecule, ethylene is spectroscopically simple. Its UV-vis spectrum is still used as a test of theoretical methods. Major industrial reactions of ethylene include in order of scale: 1) polymerization , 2) oxidation , 3) halogenation and hydrohalogenation , 4) alkylation , 5) hydration , 6) oligomerization , and 7) hydroformylation . In

1188-613: The ever-increasing demand for ethylene, sharp increases in production facilities are added globally, particularly in the Mideast and in China . Production emits greenhouse gas , namely significant amounts of carbon dioxide. Ethylene is produced by several methods in the petrochemical industry . A primary method is steam cracking (SC) where hydrocarbons and steam are heated to 750–950 °C. This process converts large hydrocarbons into smaller ones and introduces unsaturation. When ethane

1232-680: The first organometallic compounds, Zeise's salt is a complex of ethylene. Useful reagents containing ethylene include Pt(PPh 3 ) 2 (C 2 H 4 ) and Rh 2 Cl 2 (C 2 H 4 ) 4 . The Rh-catalysed hydroformylation of ethylene is conducted on an industrial scale to provide propionaldehyde . Some geologists and scholars believe that the famous Greek Oracle at Delphi (the Pythia ) went into her trance-like state as an effect of ethylene rising from ground faults. Ethylene appears to have been discovered by Johann Joachim Becher , who obtained it by heating ethanol with sulfuric acid; he mentioned

1276-817: The gas in his Physica Subterranea (1669). Joseph Priestley also mentions the gas in his Experiments and observations relating to the various branches of natural philosophy: with a continuation of the observations on air (1779), where he reports that Jan Ingenhousz saw ethylene synthesized in the same way by a Mr. Enée in Amsterdam in 1777 and that Ingenhousz subsequently produced the gas himself. The properties of ethylene were studied in 1795 by four Dutch chemists, Johann Rudolph Deimann, Adrien Paets van Troostwyck, Anthoni Lauwerenburgh and Nicolas Bondt, who found that it differed from hydrogen gas and that it contained both carbon and hydrogen. This group also discovered that ethylene could be combined with chlorine to produce

1320-447: The general formula R−SO 2 −OR. Sulfonic esters such as methyl triflate are considered good alkylating agents in organic synthesis . Such sulfonate esters are often prepared by alcoholysis of the sulfonyl chlorides: Sulfonyl halide groups (R−SO 2 −X) are produced by chlorination of sulfonic acids using thionyl chloride . Sulfonyl fluorides can be produced by treating sulfonic acids with sulfur tetrafluoride : Although strong,

1364-492: The hydrocarbons using the Reed reaction . Vinylsulfonic acid is derived by hydrolysis of carbyl sulfate , ( C 2 H 4 (SO 3 ) 2 ), which in turn is obtained by the addition of sulfur trioxide to ethylene . Sulfonic acids are strong acids. They are commonly cited as being around a million times stronger than the corresponding carboxylic acid. For example, p -Toluenesulfonic acid and methanesulfonic acid have p K

Perfluorosulfonic acids - Misplaced Pages Continue

1408-531: The initial complexation of ethylene to a Pd(II) center. Major intermediates from the halogenation and hydrohalogenation of ethylene include ethylene dichloride , ethyl chloride , and ethylene dibromide . The addition of chlorine entails " oxychlorination ", i.e. chlorine itself is not used. Some products derived from this group are polyvinyl chloride , trichloroethylene , perchloroethylene , methyl chloroform , polyvinylidene chloride and copolymers , and ethyl bromide . Major chemical intermediates from

1452-492: The mechanism for the fused alkali hydrolysis of chlorobenzene, which proceeds through elimination-addition ( benzyne mechanism), benzenesulfonic acid undergoes the analogous conversion by an S N Ar mechanism, as revealed by a C labeling, despite the lack of stabilizing substituents. Sulfonic acids with electron-withdrawing groups (e.g., with NO 2 or CN substituents) undergo this transformation much more readily. Arylsulfonic acids react with two equiv of butyl lithium to give

1496-518: The name ethylene was deeply entrenched, and it remains in wide use today, especially in the chemical industry. Following experimentation by Luckhardt, Crocker, and Carter at the University of Chicago, ethylene was used as an anesthetic. It remained in use through the 1940s use even while chloroform was being phased out. Its pungent odor and its explosive nature limit its use today. The 1979 IUPAC nomenclature rules made an exception for retaining

1540-451: The non-systematic name ethylene ; however, this decision was reversed in the 1993 rules, and it remains unchanged in the newest 2013 recommendations, so the IUPAC name is now ethene . In the IUPAC system, the name ethylene is reserved for the divalent group -CH 2 CH 2 -. Hence, names like ethylene oxide and ethylene dibromide are permitted, but the use of the name ethylene for

1584-448: The ortho-lithio derivatives, i.e. ortho-lithiation . These dilithio compounds are poised for reactions with many electrophiles. Ethylene Ethylene ( IUPAC name: ethene ) is a hydrocarbon which has the formula C 2 H 4 or H 2 C=CH 2 . It is a colourless, flammable gas with a faint "sweet and musky " odour when pure. It is the simplest alkene (a hydrocarbon with carbon–carbon double bonds ). Ethylene

1628-441: The process of sulfonation . Usually the sulfonating agent is sulfur trioxide . A large scale application of this method is the production of alkylbenzenesulfonic acids : In this reaction, sulfur trioxide is an electrophile and the arene is the nucleophile. The reaction is an example of electrophilic aromatic substitution . Alkylsulfonic acids can be prepared by many methods. In sulfoxidation , alkanes are irradiated with

1672-444: The production of surfactants and detergents by ethoxylation . Ethylene oxide is also hydrolyzed to produce ethylene glycol , widely used as an automotive antifreeze as well as higher molecular weight glycols, glycol ethers , and polyethylene terephthalate . Ethylene oxidation in the presence of a palladium catalyst can form acetaldehyde . This conversion remains a major industrial process (10M kg/y). The process proceeds via

1716-650: The sodium sulfonate and hydrogen chloride. This property implies an acidity within two or three orders of magnitude of that of HCl (g) , whose p K a was recently accurately determined (p K a = −5.9). Because of their polarity, sulfonic acids tend to be crystalline solids or viscous, high-boiling liquids. They are also usually colourless and nonoxidizing, which makes them suitable for use as acid catalysts in organic reactions. Their polarity, in conjunction with their high acidity, renders short-chain sulfonic acids water-soluble, while longer-chain ones exhibit detergent-like properties. The structure of sulfonic acids

1760-582: The suffixes -ane, -ene, -ine, -one, and -une were used to denote the hydrocarbons with 0, 2, 4, 6, and 8 fewer hydrogens than their parent alkane . In this system, ethylene became ethene . Hofmann's system eventually became the basis for the Geneva nomenclature approved by the International Congress of Chemists in 1892, which remains at the core of the IUPAC nomenclature. However, by that time,

1804-415: The sulfonate behaves as a pseudohalide leaving group. Arylsulfonic acids are susceptible to hydrolysis, the reverse of the sulfonation reaction: Whereas benzenesulfonic acid hydrolyzes above 200 °C, many derivatives are easier to hydrolyze. Thus, heating aryl sulfonic acids in aqueous acid produces the parent arene. This reaction is employed in several scenarios. In some cases the sulfonic acid serves as

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1848-532: The two-carbon alkene is not. Nevertheless, use of the name ethylene for H 2 C=CH 2 (and propylene for H 2 C=CHCH 3 ) is still prevalent among chemists in North America. "A key factor affecting petrochemicals life-cycle emissions is the methane intensity of feedstocks, especially in the production segment." Emissions from cracking of naptha and natural gas (common in the US as gas is cheap there) depend

1892-672: Was included in Annex B of the Stockholm Convention in 2009 and subsequently in the EU POPs Regulation . Perfluorohexanesulfonic acid was included in Annex B of the Stockholm Convention in 2022. Alkanesulfonic acids In organic chemistry , sulfonic acid (or sulphonic acid ) refers to a member of the class of organosulfur compounds with the general formula R−S(=O) 2 −OH , where R

1936-454: Was widely used to refer to a molecule or part thereof that contained one fewer hydrogen atoms than the molecule being modified. Thus, ethylene ( C 2 H 4 ) was the "daughter of ethyl " ( C 2 H 5 ). The name ethylene was used in this sense as early as 1852. In 1866, the German chemist August Wilhelm von Hofmann proposed a system of hydrocarbon nomenclature in which

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