1-Propanol Explained

1-Propanol (also propan-1-ol, propanol, n-propyl alcohol) is a primary alcohol with the formula and sometimes represented as PrOH or n-PrOH. It is a colourless liquid and an isomer of 2-propanol. 1-Propanol is used as a solvent in the pharmaceutical industry, mainly for resins and cellulose esters, and, sometimes, as a disinfecting agent.

Occurrence

Fusel alcohols like 1-Propanol are grain fermentation byproducts, and therefore trace amounts of 1-Propanol are present in many alcoholic beverages.

Chemical properties

1-Propanol shows the normal reactions of a primary alcohol. Thus it can be converted to alkyl halides; for example red phosphorus and iodine produce n-propyl iodide in 80% yield, while with catalytic gives n-propyl chloride. Reaction with acetic acid in the presence of an catalyst under Fischer esterification conditions gives propyl acetate, while refluxing propanol overnight with formic acid alone can produce propyl formate in 65% yield. Oxidation of 1-propanol with and gives a 36% yield of propionaldehyde, and therefore for this type of reaction higher yielding methods using PCC or the Swern oxidation are recommended. Oxidation with chromic acid yields propionic acid.

Preparation

1-Propanol is manufactured by catalytic hydrogenation of propionaldehyde. Propionaldehyde is produced via the oxo process by hydroformylation of ethylene using carbon monoxide and hydrogen in the presence of a catalyst such as cobalt octacarbonyl or a rhodium complex.[1]

A traditional laboratory preparation of 1-propanol involves treating n-propyl iodide with moist .

Safety

1-Propanol is thought to be similar to ethanol in its effects on the human body, but 2–4 times more potent according to a study conducted on rabbits. Many toxicology studies find oral acute LD50 ranging from 1.9 g/kg to 6.5 g/kg (compared to 7.06 g/kg for ethanol). It is metabolized into propionic acid. Effects include alcoholic intoxication and high anion gap metabolic acidosis. As of 2011, one case of lethal poisoning was reported following oral ingestion of 500mL of 1-propanol.[2] Due to lack of long term data, the carcinogenicity of 1-propanol in human beings is unknown.

1-Propanol as fuel

1-Propanol has high octane number and is suitable for engine fuel usage. However, propanol is too expensive to use as a motor fuel. The research octane number (RON) of propanol is 118, and anti-knock index (AKI) is 108.[3]

Further reading

    1. Book: Lide DR. 87th. TF-CRC. 2006. 0849304873. CRC Handbook of Chemistry and Physics.
  1. Book: O'Neil MJ. 14th. Merck. 2006. 091191000X. The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals.
  2. Book: Organic Chemistry. W. & R. Chambers. 1922. Perkin WH, Kipping FS. London. 0080223540.

External links

Notes and References

  1. Book: Ullmann's Encyclopedia of Industrial Chemistry. Papa AJ. Wiley-VCH. 2011. 9783527303854. Weinheim. Propanols. 10.1002/14356007.a22_173.pub2.
  2. Web site: N-PROPANOL Health-Base Assessment and Recommendation for HEAC. Unmack JL. 2011.
  3. Web site: Bioalcohols . 2010 . Biofuel.org.uk . 16 Apr 2014.