Ethyl acetate

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Structural formula
Structural formula of ethyl acetate
General
Surname Ethyl acetate
other names
  • Ethyl acetate ( IUPAC )
  • Ethyl ethanoate (system. IUPAC )
  • Ethanoic acid ethyl ester
  • Ethyl acetate
  • ESTP
  • Ethyl acetate
Molecular formula C 4 H 8 O 2
Brief description

colorless liquid with a fruity odor

External identifiers / databases
CAS number 141-78-6
EC number 205-500-4
ECHA InfoCard 100.005.001
PubChem 8857
Wikidata Q407153
properties
Molar mass 88.11 g mol −1
Physical state

liquid

density

0.894 g cm −3 (25 ° C)

Melting point

−83 ° C

boiling point

77 ° C

Vapor pressure
  • 98.4 h Pa (20 ° C)
  • 160 hPa (30 ° C)
  • 251 hPa (40 ° C)
  • 380 hPa (50 ° C)
solubility

moderate in water (85.3 g l −1 at 20 ° C)

Refractive index

1.372

safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary
02 - Highly / extremely flammable 07 - Warning

danger

H and P phrases H: 225-319-336
EUH: 066
P: 210-233-240-305 + 351 + 338-403 + 235
MAK
  • DFG : 200 ml m −3 or 750 mg m −3
  • Switzerland: 200 ml m −3 or 730 mg m −3
Toxicological data

5620 mg kg −1 ( LD 50 ,  rat ,  oral )

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Ethyl acetate , also called ethyl acetate or often referred to as ethyl acetate for short , is a chemical compound from the group of carboxylic acid esters . It is the ester formed from acetic acid and ethanol . The colorless liquid is a characteristic fruity-smelling solvent that is often used in the chemical industry and laboratories.

Extraction and presentation

Esterification

One of the large-scale manufacturing processes in the chemical industry is based on the acid-catalyzed esterification of acetic acid with ethanol :

Production of ethyl acetate from ethanol and acetic acid

According to Le Chatelier's principle ( law of mass action ), this equilibrium reaction is shifted to the side of the products through continuous separation of the water produced or continuous removal of the ester.

Tishchenko reaction

The Tishchenko reaction is another way of producing ethyl acetate . Then acetaldehyde is reacted at temperatures of 0-5 ° C. in the presence of aluminum triethanolate solution in a stirred tank cascade.

Tishchenko reaction of acetaldehyde to ethyl acetate in the presence of aluminum ethoxide as a catalyst

At 95% conversion , the selectivity of ethyl acetate reaches about 96% (based on acetaldehyde). The main by-product is acetaldol , which is produced by the aldol addition of acetaldehyde. The product mixture is separated in a continuous distillation column and the ethyl acetate is distilled off.

This process is carried out especially in regions with inexpensive availability of acetaldehyde (especially Europe and Japan ) and in countries with economically unattractive ethanol prices .

properties

Physical Properties

Under normal conditions, ethyl acetate is a colorless, low-viscosity and flammable liquid. The melting point is −83 ° C, with a melting enthalpy of 10.48 kJ · mol −1 . At normal pressure , the compound boils at 77 ° C. The heat of vaporization at the boiling point is 31.94 kJ mol −1 . According to Antoine, the vapor pressure function results from log 10 (P) = A− (B / (T + C)) (P in bar, T in K) with A = 4.22809, B = 1245.702 and C = −55.189 in the temperature range from 289 K to 349 K. The temperature dependence of the enthalpy of vaporization can be calculated according to the equation Δ V H 0 = Aexp (−βT r ) (1 − T r ) β (Δ V H 0 in kJ / mol, T r = ( Describe T / T c ) reduced temperature) with A = 54.26 kJ / mol, β = 0.2982 and T c = 523.2 K in the temperature range between 298 K and 363 K.

Compilation of the most important thermodynamic properties
property Type value Remarks
Standard enthalpy of formation Δ f H 0 liquid
Δ f H 0 gas 		−480.57 kJ mol −1
−445.43 kJ mol −1 		as a liquid
as a gas
Standard entropy S 0 liquid
S 0 gas 		259.4 J mol −1 K −1
362.75 J mol −1 K −1 		as a liquid
as a gas
Enthalpy of combustion Δ c H 0 liquid −2235.4 kJ mol −1
Heat capacity c p 168.94 J mol −1 K −1 (25 ° C)
1.92 J g −1 K −1 (25 ° C)
113.64 J mol −1 K −1 (25 ° C )
1.29 J g −1 K −1 (25 ° C) 		as a liquid

as a gas
Critical temperature T c 523.2 K
Critical pressure p c 38.82 bar
Critical density ρ c 3.497 mol·l −1
Acentric factor ω c 0.36641

Approx. 8 ml of ethyl acetate dissolve in 100 ml of water at 20 ° C. The compound forms azeotropic mixtures with water and many organic solvents. The azeotrope with water contains 8.43% water at normal pressure and boils at 70.38 ° C. The azeotrope composition and the azeotrope boiling point are pressure dependent. With decreasing pressure, the water content in the azeotropic mixture and its boiling point decrease.

Pressure dependence of the azeotrope composition and the azeotrope boiling point
p in Torr 25th 50 75 100 200 300 400 500 600 700 760 800 900 1000 1100 1200 1300 1400 1500
p in mbar 33 67 100 133 267 400 533 667 800 933 1013 1067 1200 1333 1467 1600 1733 1866 2000
x (H 2 O) in% 3.60 4.00 4.36 4.70 5.79 6.56 7.11 7.54 7.92 8.25 8.43 8.54 8.80 9.04 9.26 9.47 9.67 9.86 10.04
T b in ° C −1.89 10.0 17.4 23.0 37.6 46.8 53.8 59.4 64.1 68.2 70.4 71.8 75.1 78.2 81.0 83.5 85.9 88.2 90.3

where 1  Torr corresponds to ≈ 133.322  Pa and 760 Torr is roughly the normal pressure at sea level.

The azeotropic compositions and boiling points with other organic solvents can be found in the following table. No azeotropes are formed with toluene , benzene , n- propanol , n- butanol , iso- butanol , sec- butanol , acetone , 1,4-dioxane , methyl acetate and isopropyl acetate .

Azeotropes with various solvents
solvent n -hexane Cyclohexane Methanol Ethanol 2-propanol
Content of ethyl acetate in% 38 54 56 69 75
boiling point in ° C 65 72 62 72 76
solvent chloroform Carbon tetrachloride Butanone Carbon disulfide Acetonitrile
Content of ethyl acetate in% 72 43 82 3 77
boiling point in ° C 78 75 77 46 75

Safety-related parameters

Ethyl acetate forms highly flammable vapor-air mixtures. The compound has a flash point of −4 ° C. The explosion range is between 2% by volume (73 g / m 3 ) as the lower explosion limit (LEL) and 12.8% by volume (470 g / m 3 ) as the upper explosion limit (UEL). A correlation of the explosion limits with the vapor pressure function results in a lower explosion point of −6 ° C and an upper explosion point of 25 ° C. The explosion limits are pressure dependent. A decrease in pressure leads to a reduction in the explosion area. The lower explosion limit changes only slightly up to a pressure of 100 mbar and only increases at pressures below 100 mbar. The upper explosion limit decreases analogously with falling pressure.

Explosion limits under reduced pressure (measured at 100 ° C)
pressure in mbar 1013 800 600 400 300 250 200 150 100 50 25th
Lower explosion limit (LEL) in% by volume 1.7 1.8 1.8 1.8 1.9 1.9 2.0 2.1 2.2 2.8 3.5
in g m −3 62 63 64 65 67 69 71 74 79 102 126
Upper explosion limit (UEL) in% by volume 12.8 12.6 12.2 11.8 11.6 11.6 11.6 11.4 11.4 9.9 8.1
in g m −3 468 461 448 433 426 419 419 426 426 364 295

The limit oxygen concentration at 20 ° C is 9.8% by volume, at 100 ° C it is 9.4% by volume. The maximum explosion pressure is 9.5 bar. The maximum explosion pressure decreases as the outlet pressure decreases.

Maximum explosion pressure under reduced pressure
pressure in mbar 1013 800 600 300 200 150 100
Maximum explosion pressure (in bar) at 20 ° C 9.2 7.1 5.4 2.6 1.8 1.4 1.1

The limit gap width was determined to be 0.95 mm (50 ° C). This results in an assignment to explosion group IIA. With a minimum ignition energy of 0.46 mJ, vapor-air mixtures are extremely ignitable. The ignition temperature is 470 ° C. The substance therefore falls into temperature class T1. The ignition temperature drops significantly with increasing pressure. The electrical conductivity of <1 · 10 −7 S · m −1 is in the middle range for liquid substances.

Ignition temperatures under increased pressure
pressure in cash 1.0 1.5 2.5 6.2 12.4
Ignition temperature in ° C 470 350 300 240 220

According to the dangerous goods regulations , ethyl acetate is assigned to class 3 (flammable liquids) with packaging group II (medium level of danger) (label: 3).

use

Ethyl acetate

Ethyl acetate is a versatile solvent. Ethyl acetate is used as an extractant , e.g. B. for the decaffeination of coffee beans or for the extraction of natural flavorings for the flavoring of lemonades , sweets and medicines . It is naturally present in small amounts in rum and some other spirits . It also occurs in small quantities in wine , especially if the grapes have been damaged by hail or rot ; it then causes a solvent tone in the wine.

It is one of the most common solvents used in adhesives . In high concentration it acts as an intoxicant that is used for sniffing .

In electricity storage technology, ethyl acetate is used as an electrolyte. The advantage of organic liquids over aqueous electrolytes is their good functionality at low temperatures. The disadvantage is the significantly lower energy density.

Due to its strong dissolving power, ethyl acetate is also used as an ingredient in nail polish removers and thinners.

In entomology , it is the most common killer used in dissecting insects .

Individual evidence

  1. ↑ a b c d e f g h i j k l m n o p Entry on ethyl acetate in the GESTIS substance database of the IFA , accessed on February 21, 2018(JavaScript required) .
  2. ↑ a b c M. Pintos, R. Bravo, MC Baluja, MI Paz Andrade, G. Roux-Desgranges, J.-PE Grolier: Thermodynamics of alkanoate + alkane binary mixtures. Concentration dependence of excess heat capacities and volumes . In: Canadian Journal of Chemistry . 66, 1988, pp. 1179-1186, doi : 10.1139 / v88-193 .
  3. ↑ CRC Handbook of Tables for Organic Compound Identification . 3. Edition. 1984, ISBN 0-8493-0303-6 .
  4. ↑ Entry on ethyl acetate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers and / or distributors can expand the harmonized classification and labeling .
  5. ↑ Swiss Accident Insurance Fund (Suva): Limit values ​​- current MAK and BAT values (search for 141-78-6 or ethyl acetate ), accessed on September 14, 2019.
  6. ↑ Entry on ethyl acetate. In: Römpp Online . Georg Thieme Verlag, accessed on September 29, 2014.
  7. ↑ a b Manfred Fedtke, Wilhelm Pritzkow, Gerhard Zimmermann: Technical organic chemistry - basic materials, intermediate products, final products, polymers . 1st edition. German publishing house for basic industry, Leipzig 1992, ISBN 3-342-00420-7 .
  8. ↑ a b c Hans-Jürgen Arpe: Industrial organic chemistry - important preliminary and intermediate products . 6th edition. Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 2007, ISBN 978-3-527-31540-6 .
  9. ↑ WE Acree, Jr .: Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation. In: Thermochim. Acta . 189, 1991, pp. 37-56. doi: 10.1016 / 0040-6031 (91) 87098-H
  10. ^ A b c V. Majer, V. Svoboda: Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation. Blackwell Scientific Publications, Oxford 1985, ISBN 0-632-01529-2 .
  11. ↑ J. Polak, I. Mertl: Saturated Vapor Pressure of Methyl Acetate, Ethyl Acetate, n-Propyl Acetate, Methyl Propionate, and Ethyl Propionate. In: Collect Czech Chem Commun . 30, 1965, pp. 3526-3528, doi: 10.1135 / cccc19653526 .
  12. ↑ a b K. B. Wiberg, LS Crocker, KM Morgan: Thermochemical studies of carbonyl compounds. 5. Enthalpies of reduction of carbonyl groups. In: J. Am. Chem. Soc. . 113, 1991, pp. 3447-3450, doi: 10.1021 / ja00009a033 .
  13. ↑ GS Parks, HM Huffman, M. Barmore: Thermal data on organic compounds. XI. The heat capacities, entropies and free energies of ten compounds containing oxygen or nitrogen. In: J. Am. Chem. Soc. 55, 1933, pp. 2733-2740, doi: 10.1021 / ja01334a016 .
  14. ↑ a b c D. R. Stull, Jr .: The Chemical Thermodynamics of Organic Compounds. Wiley, New York 1969.
  15. ↑ ME Butwill, JD Rockfeller: Heats of combustion and formation of ethyl acetate and isopropyl acetate. In: Thermochim. Acta . 1, 1970, pp. 289-295, doi: 10.1016 / 0040-6031 (70) 80033-8 .
  16. ↑ D. Ambrose, JH Ellender, HA Gundry, DA Lee, R. Townsend: Thermodynamic properties of organic oxygen compounds. LI. The vapor pressures of some esters and fatty acids. In: J. Chem. Thermodyn. . 13, 1981, pp. 795-802. doi: 10.1016 / 0021-9614 (81) 90069-0
  17. ^ S. Young, GL Thomas: The vapor pressures, molecular volumes, and critical constants of ten of the lower esters. In: J. Chem. Soc. . 63, 1893, p. 1191.
  18. ↑ J. Schmidt: Design of safety valves for multi-purpose systems according to ISO 4126-10. In: . Chem. Ing Techn. . 83, 2011, pp. 796-812. doi: 10.1002 / cite.201000202
  19. ↑ a b c R. W. Merriman: The Azeotropic Mixtures of Ethyl Acetate, Ethyl Alcohol and Water at Pressures Above and Below the Atmospheric Pressure. Part 1. In: J. Chem. Soc. Trans. 103, 1913, pp. 1790-1801.
  20. ↑ a b I. M. Smallwood: Handbook of organic solvent properties. Arnold, London 1996, ISBN 0-340-64578-4 , pp. 227-229.
  21. ↑ a b c d e f E. Brandes, W. Möller: Safety-related parameters. Volume 1: Flammable Liquids and Gases. Wirtschaftsverlag NW - Verlag für neue Wissenschaft, Bremerhaven 2003, ISBN 3-89701-745-8 .
  22. ↑ a b c d D. Pawel, E. Brandes: Final report on the research project, the dependence of safety parameters on the pressure below atmospheric pressure. ( Memento of December 2, 2013 in the Internet Archive ), Physikalisch-Technische Bundesanstalt (PTB), Braunschweig 1998.
  23. ↑ Osterberg PM, JK Niemeier, CJ Welch, JM Hawkins, JR Martinelli, TE Johnson, TW Root, SS Stahl: Experimental Limiting Oxygen Concentrations for Nine Organic Solvents at Temperatures and Pressures Relevant to Aerobic Oxidations in the Pharmaceutical Industry. In: .. Org Process Res Dev. . 19, 2015, pp. 1537-1542. doi: 10.1021 / op500328f
  24. ↑ a b Technical rule for operational safety - TRBS 2153, BG RCI leaflet T033 Avoidance of ignition hazards due to electrostatic charges. As of April 2009, Jedermann-Verlag, Heidelberg.
  25. ↑ a b Möller, W .; Sturm, R .: DECHEMA ChemSafe database , accessed on November 8, 2017.