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Acetylene

Acetylene
Acetylene
Acetylene
Acetylene – space-filling model
space-filling model of solid acetylene
Names
Preferred IUPAC name
Acetylene[1][2]
Systematic IUPAC name
Ethyne[3]
Identifiers
3D model (JSmol)
906677
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.743 Edit this at Wikidata
EC Number
  • 200-816-9
210
KEGG
RTECS number
  • AO9600000
UNII
UN number 1001 (dissolved)
3138 (in mixture with ethylene and propylene)
  • InChI=1S/C2H2/c1-2/h1-2H checkY
    Key: HSFWRNGVRCDJHI-UHFFFAOYSA-N checkY
  • InChI=1/C2H2/c1-2/h1-2H
    Key: HSFWRNGVRCDJHI-UHFFFAOYAY
  • C#C
Properties
C2H2
Molar mass 26.038 g·mol−1
Appearance Colorless gas
Odor Odorless
Density 1.1772 g/L = 1.1772 kg/m3 (0 °C, 101.3 kPa)[4]
Melting point −80.8 °C (−113.4 °F; 192.3 K) Triple point at 1.27 atm
−84 °C; −119 °F; 189 K (1 atm)
slightly soluble
Solubility slightly soluble in alcohol
soluble in acetone, benzene
Vapor pressure 44.2 atm (20 °C)[5]
Acidity (pKa) 25[6]
Conjugate acid Ethynium
−20.8×10−6 cm3/mol [7]
Thermal conductivity 21.4 mW·m−1·K−1 (300 K) [7]
Structure
Linear
Thermochemistry[7]
44.036 J·mol−1·K−1
200.927 J·mol−1·K−1
227.400 kJ·mol−1
209.879 kJ·mol−1
1300 kJ·mol−1
Hazards
GHS labelling:
GHS02: FlammableGHS07: Exclamation mark
Danger
H220, H336
P202, P210, P233, P261, P271, P304, P312, P340, P377, P381, P403, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g. propaneInstability 3: Capable of detonation or explosive decomposition but requires a strong initiating source, must be heated under confinement before initiation, reacts explosively with water, or will detonate if severely shocked. E.g. hydrogen peroxideSpecial hazards (white): no code
1
4
3
300 °C (572 °F; 573 K)
Explosive limits 2.5–100%
NIOSH (US health exposure limits):
PEL (Permissible)
none[5]
REL (Recommended)
C 2500 ppm (2662 mg/m3)[5]
IDLH (Immediate danger)
N.D.[5]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Acetylene (systematic name: ethyne) is the chemical compound with the formula C2H2 and structure H−C≡C−H. It is a hydrocarbon and the simplest alkyne.[8] This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure form and thus is usually handled as a solution.[9] Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities such as divinyl sulfide and phosphine.[9][10]

As an alkyne, acetylene is unsaturated because its two carbon atoms are bonded together in a triple bond. The carbon–carbon triple bond places all four atoms in the same straight line, with CCH bond angles of 180°.[11]

Discovery

Acetylene was discovered in 1836 by Edmund Davy, who identified it as a "new carburet of hydrogen".[12][13] It was an accidental discovery while attempting to isolate potassium metal. By heating potassium carbonate with carbon at very high temperatures, he produced a residue of what is now known as potassium carbide, (K2C2), which reacted with water to release the new gas. It was rediscovered in 1860 by French chemist Marcellin Berthelot, who coined the name acétylène.[14] Berthelot's empirical formula for acetylene (C4H2), as well as the alternative name "quadricarbure d'hydrogène" (hydrogen quadricarbide), were incorrect because many chemists at that time used the wrong atomic mass for carbon (6 instead of 12).[15] Berthelot was able to prepare this gas by passing vapours of organic compounds (methanol, ethanol, etc.) through a red hot tube and collecting the effluent. He also found that acetylene was formed by sparking electricity through mixed cyanogen and hydrogen gases. Berthelot later obtained acetylene directly by passing hydrogen between the poles of a carbon arc.[16][17]

Preparation

Partial combustion of hydrocarbons

Since the 1950s, acetylene has mainly been manufactured by the partial combustion of methane in the US, much of the EU, and many other countries:[9][18][19]

3 CH4 + 3 O2 → C2H2 + CO + 5 H2O

It is a recovered side product in production of ethylene by cracking of hydrocarbons. Approximately 400,000 tonnes were produced by this method in 1983.[9] Its presence in ethylene is usually undesirable because of its explosive character and its ability to poison Ziegler–Natta catalysts. It is selectively hydrogenated into ethylene, usually using PdAg catalysts.[20]

Dehydrogenation of alkanes

The heaviest alkanes in petroleum and natural gas are cracked into lighter molecules which are dehydrogenated at high temperature:

C2H6 → C2H2 + 2 H2
2 CH4 → C2H2 + 3 H2

This last reaction is implemented in the process of anaerobic decomposition of methane by microwave plasma.[21][non-primary source needed]

Carbochemical method

The first acetylene produced was by Edmund Davy in 1836, via postassium carbide.[22] Acetylene was historically produced by hydrolysis (reaction with water) of calcium carbide:

CaC2 + 2 H2O → Ca(OH)2 + C2H2

This reaction was discovered by Friedrich Wöhler in 1862,[23] but a suitable commercial scale production method which allowed acetylene to be put into wider scale use was not found until 1892 by the Canadian inventor Thomas Willson while searching for a viable commercial production method for aluminum.[24]

As late as the early 21st century, China, Japan, and Eastern Europe produced acetylene primarily by this method.[25]

The use of this technology has since declined worldwide with the notable exception of China, with its emphasis on coal-based chemical industry, as of 2013. Otherwise oil has increasingly supplanted coal as the chief source of reduced carbon.[26]

Calcium carbide production requires high temperatures, ~2000 °C, necessitating the use of an electric arc furnace. In the US, this process was an important part of the late-19th century revolution in chemistry enabled by the massive hydroelectric power project at Niagara Falls.[27]

Bonding

In terms of valence bond theory, in each carbon atom the 2s orbital hybridizes with one 2p orbital thus forming an sp hybrid. The other two 2p orbitals remain unhybridized. The two ends of the two sp hybrid orbital overlap to form a strong σ valence bond between the carbons, while on each of the other two ends hydrogen atoms attach also by σ bonds. The two unchanged 2p orbitals form a pair of weaker π bonds.[28]

Since acetylene is a linear symmetrical molecule, it possesses the D∞h point group.[29]

Physical properties

Changes of state

At atmospheric pressure, acetylene cannot exist as a liquid and does not have a melting point. The triple point on the phase diagram corresponds to the melting point (−80.8 °C) at the minimal pressure at which liquid acetylene can exist (1.27 atm). At temperatures below the triple point, solid acetylene can change directly to the vapour (gas) by sublimation. The sublimation point at atmospheric pressure is −84.0 °C.[30]

Other

At room temperature, the solubility of acetylene in acetone is 27.9 g per kg. For the same amount of dimethylformamide (DMF), the solubility is 51 g. At 20.26 bar, the solubility increases to 689.0 and 628.0 g for acetone and DMF, respectively. These solvents are used in pressurized gas cylinders.[31]

Applications

Welding

Approximately 20% of acetylene is supplied by the industrial gases industry for oxyacetylene gas welding and cutting due to the high temperature of the flame. Combustion of acetylene with oxygen produces a flame of over 3,600 K (3,330 °C; 6,020 °F), releasing 11.8 kJ/g. Oxygen with acetylene is the hottest burning common gas mixture.[32] Acetylene is the third-hottest natural chemical flame after dicyanoacetylene's 5,260 K (4,990 °C; 9,010 °F) and cyanogen at 4,798 K (4,525 °C; 8,177 °F). Oxy-acetylene welding was a popular welding process in previous decades. The development and advantages of arc-based welding processes have made oxy-fuel welding nearly extinct for many applications. Acetylene usage for welding has dropped significantly. On the other hand, oxy-acetylene welding equipment is quite versatile – not only because the torch is preferred for some sorts of iron or steel welding (as in certain artistic applications), but also because it lends itself easily to brazing, braze-welding, metal heating (for annealing or tempering, bending or forming), the loosening of corroded nuts and bolts, and other applications. Bell Canada cable-repair technicians still use portable acetylene-fuelled torch kits as a soldering tool for sealing lead sleeve splices in manholes and in some aerial locations. Oxyacetylene welding may also be used in areas where electricity is not readily accessible. Oxyacetylene cutting is used in many metal fabrication shops. For use in welding and cutting, the working pressures must be controlled by a regulator, since above 15 psi (100 kPa), if subjected to a shockwave (caused, for example, by a flashback), acetylene decomposes explosively into hydrogen and carbon.[33]

Acetylene fuel container/burner as used in the island of Bali

Chemicals

Acetylene is useful for many processes, but few are conducted on a commercial scale.[34]

One of the major chemical applications is ethynylation of formaldehyde.[9] Acetylene adds to aldehydes and ketones to form α-ethynyl alcohols:

The reaction gives butynediol, with propargyl alcohol as the by-product. Copper acetylide is used as the catalyst.[35][36]

In addition to ethynylation, acetylene reacts with carbon monoxide, acetylene reacts to give acrylic acid, or acrylic esters. Metal catalysts are required. These derivatives form products such as acrylic fibers, glasses, paints, resins, and polymers. Except in China, use of acetylene as a chemical feedstock has declined by 70% from 1965 to 2007 owing to cost and environmental considerations.[37] In China, acetylene is a major precursor to vinyl chloride.[34]

Historical uses

Prior to the widespread use of petrochemicals, coal-derived acetylene was a building block for several industrial chemicals. Thus acetylene can be hydrated to give acetaldehyde, which in turn can be oxidized to acetic acid. Processes leading to acrylates were also commercialized. Almost all of these processes became obsolete with the availability of petroleum-derived ethylene and propylene.[38]

Niche applications

In 1881, the Russian chemist Mikhail Kucherov[39] described the hydration of acetylene to acetaldehyde using catalysts such as mercury(II) bromide. Before the advent of the Wacker process, this reaction was conducted on an industrial scale.[40]

The polymerization of acetylene with Ziegler–Natta catalysts produces polyacetylene films. Polyacetylene, a chain of CH centres with alternating single and double bonds, was one of the first discovered organic semiconductors. Its reaction with iodine produces a highly electrically conducting material. Although such materials are not useful, these discoveries led to the developments of organic semiconductors, as recognized by the Nobel Prize in Chemistry in 2000 to Alan J. Heeger, Alan G MacDiarmid, and Hideki Shirakawa.[9]

In the 1920s, pure acetylene was experimentally used as an inhalation anesthetic.[41]

Acetylene is sometimes used for carburization (that is, hardening) of steel when the object is too large to fit into a furnace.[42]

Acetylene is used to volatilize carbon in radiocarbon dating. The carbonaceous material in an archeological sample is treated with lithium metal in a small specialized research furnace to form lithium carbide (also known as lithium acetylide). The carbide can then be reacted with water, as usual, to form acetylene gas to feed into a mass spectrometer to measure the isotopic ratio of carbon-14 to carbon-12.[43]

Acetylene combustion produces a strong, bright light and the ubiquity of carbide lamps drove much acetylene commercialization in the early 20th century. Common applications included coastal lighthouses,[44] street lights,[45] and automobile[46] and mining headlamps.[47] In most of these applications, direct combustion is a fire hazard, and so acetylene has been replaced, first by incandescent lighting and many years later by low-power/high-lumen LEDs. Nevertheless, acetylene lamps remain in limited use in remote or otherwise inaccessible areas and in countries with a weak or unreliable central electric grid.[47]

Natural occurrence

The energy richness of the C≡C triple bond and the rather high solubility of acetylene in water make it a suitable substrate for bacteria, provided an adequate source is available.[48] A number of bacteria living on acetylene have been identified. The enzyme acetylene hydratase catalyzes the hydration of acetylene to give acetaldehyde:[49]

C2H2 + H2O → CH3CHO

Acetylene is a moderately common chemical in the universe, often associated with the atmospheres of gas giants.[50] One curious discovery of acetylene is on Enceladus, a moon of Saturn. Natural acetylene is believed to form from catalytic decomposition of long-chain hydrocarbons at temperatures of 1,700 K (1,430 °C; 2,600 °F) and above. Since such temperatures are highly unlikely on such a small distant body, this discovery is potentially suggestive of catalytic reactions within that moon, making it a promising site to search for prebiotic chemistry.[51][52]

Reactions

Vinylation reactions

In vinylation reactions, H−X compounds add across the triple bond. Alcohols and phenols add to acetylene to give vinyl ethers. Thiols give vinyl thioethers. Similarly, vinylpyrrolidone and vinylcarbazole are produced industrially by vinylation of 2-pyrrolidone and carbazole.[31][9]

The hydration of acetylene is a vinylation reaction, but the resulting vinyl alcohol isomerizes to acetaldehyde. The reaction is catalyzed by mercury salts. This reaction once was the dominant technology for acetaldehyde production, but it has been displaced by the Wacker process, which affords acetaldehyde by oxidation of ethylene, a cheaper feedstock. A similar situation applies to the conversion of acetylene to the valuable vinyl chloride by hydrochlorination vs the oxychlorination of ethylene.

Vinyl acetate is used instead of acetylene for some vinylations, which are more accurately described as transvinylations.[53] Higher esters of vinyl acetate have been used in the synthesis of vinyl formate.

Organometallic chemistry

Acetylene and its derivatives (2-butyne, diphenylacetylene, etc.) form complexes with transition metals. Its bonding to the metal is somewhat similar to that of ethylene complexes. These complexes are intermediates in many catalytic reactions such as alkyne trimerisation to benzene, tetramerization to cyclooctatetraene,[9] and carbonylation to hydroquinone:[54]

Fe(CO)5 + 4 C2H2 + 2 H2O → 2 C6H4(OH)2 + FeCO3 at basic conditions (50–80 °C, 20–25 atm).

Metal acetylides, species of the formula LnM−C2R, are also common. Copper(I) acetylide and silver acetylide can be formed in aqueous solutions with ease due to a favorable solubility equilibrium.[55]

Acid-base reactions

Acetylene has a pKa of 25, acetylene can be deprotonated by a superbase to form an acetylide:[55]

Various organometallic[56] and inorganic[57] reagents are effective.

The New acetylene plant of BASF, commissioned in 2020

Hydrogenation

Acetylene can be semihydrogenated to ethylene, providing a feedstock for a variety of polyethylene plastics. Halogens add to the triple bond.

Safety and handling

Acetylene is not especially toxic, but when generated from calcium carbide, it can contain toxic impurities such as traces of phosphine and arsine, which gives it a distinct garlic-like smell. It is also highly flammable, as are most light hydrocarbons, hence its use in welding. Its most singular hazard is associated with its intrinsic instability, especially when it is pressurized: under certain conditions acetylene can react in an exothermic addition-type reaction to form a number of products, typically benzene and/or vinylacetylene, possibly in addition to carbon and hydrogen.[citation needed] Consequently, acetylene, if initiated by intense heat or a shockwave, can decompose explosively if the absolute pressure of the gas exceeds about 200 kilopascals (29 psi). Most regulators and pressure gauges on equipment report gauge pressure, and the safe limit for acetylene therefore is 101 kPagage, or 15 psig.[58][59] It is therefore supplied and stored dissolved in acetone or dimethylformamide (DMF),[59][60][61] contained in a gas cylinder with a porous filling, which renders it safe to transport and use, given proper handling. Acetylene cylinders should be used in the upright position to avoid withdrawing acetone during use.[62]

Information on safe storage of acetylene in upright cylinders is provided by the OSHA,[63][64] Compressed Gas Association,[59] United States Mine Safety and Health Administration (MSHA),[65] EIGA,[62] and other agencies.

Copper catalyses the decomposition of acetylene, and as a result acetylene should not be transported in copper pipes.[66]

Cylinders should be stored in an area segregated from oxidizers to avoid exacerbated reaction in case of fire/leakage.[59][64] Acetylene cylinders should not be stored in confined spaces, enclosed vehicles, garages, and buildings, to avoid unintended leakage leading to explosive atmosphere.[59][64] In the US, National Electric Code (NEC) requires consideration for hazardous areas including those where acetylene may be released during accidents or leaks.[67] Consideration may include electrical classification and use of listed Group A electrical components in US.[67] Further information on determining the areas requiring special consideration is in NFPA 497.[68] In Europe, ATEX also requires consideration for hazardous areas where flammable gases may be released during accidents or leaks.[62]

References

  1. ^ Favre, Henri A.; Powell, Warren H. (2014). Nomenclature of Organic Chemistry. IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. p. 375. doi:10.1039/9781849733069. ISBN 978-0-85404-182-4. The name acetylene is retained for the compound HC≡CH. It is the preferred IUPAC name, but substitution of any kind is not allowed; however, in general nomenclature, substitution is allowed, for example fluoroacetylene [fluoroethyne (PIN)], but not by alkyl groups or any other group that extends the carbon chain, nor by characteristic groups expressed by suffixes.
  2. ^ Moss, G.P. (web version). "P-14.3 Locants". Nomenclature of Organic Chemistry. IUPAC Recommendations and Preferred Names 2013. London: Queen Mary University. Section P-14.3.4.2 (d). Retrieved 24 August 2024.
  3. ^ Acyclic Hydrocarbons. Rule A-3. Unsaturated Compounds and Univalent Radicals Archived 10 October 2000 at the Wayback Machine, IUPAC Nomenclature of Organic Chemistry
  4. ^ Record of Acetylene in the GESTIS Substance Database of the Institute for Occupational Safety and Health
  5. ^ a b c d NIOSH Pocket Guide to Chemical Hazards. "#0008". National Institute for Occupational Safety and Health (NIOSH).
  6. ^ "Acetylene – Gas Encyclopedia Air Liquide". Air Liquide. Archived from the original on 4 May 2022. Retrieved 27 September 2018.
  7. ^ a b c William M. Haynes; David R. Lide; Thomas J. Bruno (2016). CRC handbook of chemistry and physics : a ready-reference book of chemical and physical data (2016-2017, 97th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4987-5428-6. OCLC 930681942. Archived from the original on 4 May 2022. Retrieved 4 May 2022.
  8. ^ R. H. Petrucci; W. S. Harwood; F. G. Herring (2002). General Chemistry (8th ed.). Prentice-Hall. p. 1072.
  9. ^ a b c d e f g h Pässler, Peter; Hefner, Werner; Buckl, Klaus; Meinass, Helmut; Meiswinkel, Andreas; Wernicke, Hans-Jürgen; Ebersberg, Günter; Müller, Richard; Bässler, Jürgen; Behringer, Hartmut; Mayer, Dieter (2008). "Acetylene Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a01_097.pub3. ISBN 978-3527306732.
  10. ^ Compressed Gas Association (1995) Material Safety and Data Sheet – Acetylene Archived 11 July 2012 at the Wayback Machine
  11. ^ Whitten K. W., Gailey K. D. and Davis R. E. General Chemistry (4th ed., Saunders College Publishing 1992), pp. 328–329, 1046. ISBN 0-03-072373-6.
  12. ^ Edmund Davy (August 1836) "Notice of a new gaseous bicarburet of hydrogen" Archived 6 May 2016 at the Wayback Machine, Report of the Sixth Meeting of the British Association for the Advancement of Science ..., 5: 62–63.
  13. ^ Miller, S. A. (1965). Acetylene: Its Properties, Manufacture and Uses. Vol. 1. Academic Press Inc. Archived from the original on 15 April 2021. Retrieved 16 July 2021.
  14. ^ Bertholet (1860) "Note sur une nouvelle série de composés organiques, le quadricarbure d'hydrogène et ses dérivés" Archived 13 July 2015 at the Wayback Machine (Note on a new series of organic compounds, tetra-carbon hydride and its derivatives), Comptes rendus, series 3, 50: 805–808.
  15. ^ Ihde, Aaron J. (1961). "The Karlsruhe Congress: A centennial retrospective". Journal of Chemical Education. 38 (2): 83. Bibcode:1961JChEd..38...83I. doi:10.1021/ed038p83. Archived from the original on 30 December 2021. Retrieved 29 December 2021. Atomic weights of 6 and 12 were both in use for carbon.
  16. ^ Berthelot (1862) "Synthèse de l'acétylène par la combinaison directe du carbone avec l'hydrogène" Archived 14 August 2020 at the Wayback Machine (Synthesis of acetylene by the direct combination of carbon with hydrogen), Comptes rendus, series 3, 54: 640–644.
  17. ^ Acetylene Archived 28 January 2012 at the Wayback Machine.
  18. ^ Habil, Phil; Sachsse, Hans (1954). "Herstellung von Acetylen durch unvollständige Verbrennung von Kohlenwasserstoffen mit Sauerstoff (Production of acetylene by incomplete combustion of hydrocarbons with oxygen)". Chemie Ingenieur Technik. 26 (5): 245–253. doi:10.1002/cite.330260502.
  19. ^ Habil, Phil; Bartholoméa, E. (1954). "Probleme großtechnischer Anlagen zur Erzeugung von Acetylen nach dem Sauerstoff-Verfahren (Problems of large-scale plants for the production of acetylene by the oxygen method)". Chemie Ingenieur Technik. 26 (5): 253–258. doi:10.1002/cite.330260503.
  20. ^ Acetylene: How Products are Made Archived 20 January 2007 at the Wayback Machine
  21. ^ "How it Works". Transform Materials. Retrieved 21 July 2023.
  22. ^ Institution, Smithsonian. "Carbide Lamps". Smithsonian Institution.
  23. ^ Wohler (1862) "Bildung des Acetylens durch Kohlenstoffcalcium" Archived 12 May 2016 at the Wayback Machine (Formation of actylene by calcium carbide), Annalen der Chemie und Pharmacie, 124: 220.
  24. ^ "A National Historic Chemical Landmark - Discovery of the Commercial Processes For Making Calcium Carbide and Acetylene - Commemorative Booklet" (PDF). American Chemical Society. ACS Office of Communications. 1998. Retrieved 10 October 2024.
  25. ^ Gannon, Richard E. (2000). "Acetylene from Hydrocarbons". Kirk-Othmer Encyclopedia of Chemical Technology. doi:10.1002/0471238961.0103052007011414.a01. ISBN 9780471484943.[need quotation to verify]
  26. ^ Holzrichter, Klaus; Knott, Alfons; Mertschenk, Bernd; Salzinger, Josef (2013). "Calcium Carbide". Ullmann's Encyclopedia of Industrial Chemistry. pp. 1–14. doi:10.1002/14356007.a04_533.pub2. ISBN 978-3-527-30673-2.
  27. ^ Freeman, Horace (1919). "Manufacture of Cyanamide". The Chemical News and the Journal of Physical Science. 117: 232. Archived from the original on 15 April 2021. Retrieved 23 December 2013.
  28. ^ Organic Chemistry 7th ed. by J. McMurry, Thomson 2008
  29. ^ Housecroft, C. E.; Sharpe, A. G. (2008). Inorganic Chemistry (3rd ed.). Prentice Hall. pp. 94–95. ISBN 978-0-13-175553-6.
  30. ^ Handbook of Chemistry and Physics (60th ed., CRC Press 1979–80), p. C-303 in Table Physical Constants of Organic Compounds (listed as ethyne).
  31. ^ a b Harreus, Albrecht Ludwig; Backes, R.; Eichler, J.-O.; Feuerhake, R.; Jäkel, C.; Mahn, U.; Pinkos, R.; Vogelsang, R. (2011). "2-Pyrrolidone". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_457.pub2. ISBN 978-3527306732.
  32. ^ "Acetylene". Products and Supply > Fuel Gases. Linde. Archived from the original on 12 January 2018. Retrieved 30 November 2013.
  33. ^ ESAB Oxy-acetylene welding handbook – Acetylene properties Archived 10 May 2020 at the Wayback Machine.
  34. ^ a b Trotuş, Ioan-Teodor; Zimmermann, Tobias; Schüth, Ferdi (2014). "Catalytic Reactions of Acetylene: A Feedstock for the Chemical Industry Revisited". Chemical Reviews. 114 (3): 1761–1782. doi:10.1021/cr400357r. PMID 24228942.
  35. ^ Gräfje, Heinz; Körnig, Wolfgang; Weitz, Hans-Martin; Reiß, Wolfgang; Steffan, Guido; Diehl, Herbert; Bosche, Horst; Schneider, Kurt; Kieczka, Heinz (15 June 2000), "Butanediols, Butenediol, and Butynediol", in Wiley-VCH Verlag GmbH & Co. KGaA (ed.), Ullmann's Encyclopedia of Industrial Chemistry, Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, pp. a04_455, doi:10.1002/14356007.a04_455, ISBN 978-3-527-30673-2, S2CID 178601434, archived from the original on 19 March 2022, retrieved 3 March 2022
  36. ^ Falbe, Jürgen; Bahrmann, Helmut; Lipps, Wolfgang; Mayer, Dieter (15 June 2000), "Alcohols, Aliphatic", in Wiley-VCH Verlag GmbH & Co. KGaA (ed.), Ullmann's Encyclopedia of Industrial Chemistry, Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, pp. a01_279, doi:10.1002/14356007.a01_279, ISBN 978-3-527-30673-2, archived from the original on 9 March 2022, retrieved 3 March 2022
  37. ^ Takashi Ohara; Takahisa Sato; Noboru Shimizu; Günter Prescher; Helmut Schwind; Otto Weiberg; Klaus Marten; Helmut Greim (2003). "Acrylic Acid and Derivatives". Ullmann's Encyclopedia of Industrial Chemistry: 7. doi:10.1002/14356007.a01_161.pub2. ISBN 3527306730.
  38. ^ Schobert, Harold (2014). "Production of Acetylene and Acetylene-based Chemicals from Coal". Chemical Reviews. 114 (3): 1743–1760. doi:10.1021/cr400276u. PMID 24256089.
  39. ^ Kutscheroff, M. (1881). "Ueber eine neue Methode direkter Addition von Wasser (Hydratation) an die Kohlenwasserstoffe der Acetylenreihe". Berichte der Deutschen Chemischen Gesellschaft. 14: 1540–1542. doi:10.1002/cber.188101401320. Archived from the original on 2 December 2020. Retrieved 9 September 2019.
  40. ^ Dmitry A. Ponomarev; Sergey M. Shevchenko (2007). "Hydration of Acetylene: A 125th Anniversary" (PDF). J. Chem. Educ. 84 (10): 1725. Bibcode:2007JChEd..84.1725P. doi:10.1021/ed084p1725. Archived (PDF) from the original on 11 June 2011. Retrieved 18 February 2009.
  41. ^ William Stanley Sykes (1930). "Acetylene in medicine". Encyclopaedia Britannica. Vol. 1 (14 ed.). p. 119.
  42. ^ "Acetylene". Products and Services. BOC. Archived from the original on 17 May 2006.
  43. ^ Geyh, Mebus (1990). "Radiocarbon dating problems using acetylene as counting gas". Radiocarbon. 32 (3): 321–324. doi:10.2458/azu_js_rc.32.1278. Archived from the original on 26 December 2013. Retrieved 26 December 2013.
  44. ^ "Lighthouse Lamps Through Time by Thomas Tag | US Lighthouse Society". uslhs.org. Archived from the original on 25 February 2017. Retrieved 24 February 2017.
  45. ^ Myers, Richard L. (2007). The 100 Most Important Chemical Compounds: A Reference Guide. ABC-CLIO. ISBN 978-0-313-33758-1. Archived from the original on 17 June 2016. Retrieved 21 November 2015.
  46. ^ Grainger, D., (2001). By cars' early light: A short history of the headlamp: 1900s lights bore port and starboard red and green lenses. National Post. [Toronto Edition] DT7.
  47. ^ a b Thorpe, Dave (2005). Carbide Light: The Last Flame in American Mines. Bergamot Publishing. ISBN 978-0976090526.
  48. ^ Akob, Denise (August 2018). "Acetylenotrophy: a hidden but ubiquitous microbial metabolism?". FEMS Microbiology Ecology. 94 (8). doi:10.1093/femsec/fiy103. PMC 7190893. PMID 29933435. Retrieved 28 July 2022.
  49. ^ ten Brink, Felix (2014). "Chapter 2. Living on acetylene. A Primordial Energy Source". In Peter M. H. Kroneck and Martha E. Sosa Torres (ed.). The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Metal Ions in Life Sciences. Vol. 14. Springer. pp. 15–35. doi:10.1007/978-94-017-9269-1_2. ISBN 978-94-017-9268-4. PMID 25416389.
  50. ^ "Precursor to Proteins and DNA found in Stellar Disk" (Press release). W. M. Keck Observatory. 20 December 2005. Archived from the original on 23 February 2007.
  51. ^ Emily Lakdawalla (17 March 2006). "LPSC: Wednesday afternoon: Cassini at Enceladus". The Planetary Society. Archived from the original on 20 February 2012.
  52. ^ John Spencer; David Grinspoon (25 January 2007). "Planetary science: Inside Enceladus". Nature. 445 (7126): 376–377. Bibcode:2007Natur.445..376S. doi:10.1038/445376b. PMID 17251967. S2CID 4427890.
  53. ^ Manchand, Percy S. (2001). "Vinyl Acetate". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rv008. ISBN 0471936235.
  54. ^ Reppe, Walter; Kutepow, N; Magin, A (1969). "Cyclization of Acetylenic Compounds". Angewandte Chemie International Edition in English. 8 (10): 727–733. doi:10.1002/anie.196907271.
  55. ^ a b Viehe, Heinz Günter (1969). Chemistry of Acetylenes (1st ed.). New York: Marcel Dekker, inc. pp. 170–179 & 225–241. ISBN 978-0824716752.
  56. ^ Midland, M. M.; McLoughlin, J. I.; Werley, Ralph T. (Jr.) (1990). "Preparation and Use of Lithium Acetylide: 1-Methyl-2-ethynyl-endo-3,3-dimethyl-2-norbornanol". Organic Syntheses. 68: 14. doi:10.15227/orgsyn.068.0014.
  57. ^ Coffman, Donald D. (1940). "Dimethylethhynylcarbinol". Organic Syntheses. 40: 20. doi:10.15227/orgsyn.020.0040.
  58. ^ "Acetylene Specification". CFC StarTec LLC. Archived from the original on 11 March 2014. Retrieved 2 May 2012.
  59. ^ a b c d e "law.resource.org CGA g-1 2009 (incorporated by reference)" (PDF). Archived (PDF) from the original on 10 October 2016. Retrieved 30 November 2016.
  60. ^ Downie, N. A. (1997). Industrial Gases. London; New York: Blackie Academic & Professional. ISBN 978-0-7514-0352-7.
  61. ^ Korzun, Mikołaj (1986). 1000 słów o materiałach wybuchowych i wybuchu. Warszawa: Wydawnictwo Ministerstwa Obrony Narodowej. ISBN 83-11-07044-X. OCLC 69535236.
  62. ^ a b c "EIGA Code of Practice: Acetylene" (PDF). Archived from the original (PDF) on 1 December 2016. Retrieved 30 November 2016.
  63. ^ "OSHA 29 CFR 1910.102 Acetylene". Archived from the original on 1 December 2016. Retrieved 30 November 2016.
  64. ^ a b c "OSHA 29 CFR 1926.350 Gas Welding and cutting". Archived from the original on 1 December 2016. Retrieved 30 November 2016.
  65. ^ Special Hazards of Acetylene Archived 24 March 2016 at the Wayback Machine UNITED STATES DEPARTMENT OF LABOR Mine Safety and Health Administration – MSHA.
  66. ^ Daniel_Sarachick (16 October 2003). "ACETYLENE SAFETY ALERT" (PDF). Office of Environmental Health & Safety (EHS). Archived (PDF) from the original on 13 July 2018. Retrieved 27 September 2018.
  67. ^ a b "NFPA free access to 2017 edition of NFPA 70 (NEC)". Archived from the original on 1 December 2016. Retrieved 30 November 2016.
  68. ^ "NFPA Free Access to NFPA 497 – Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas". Archived from the original on 1 December 2016. Retrieved 30 November 2016.