Butyl Glycol

What is Butyl Glycol? 

Butyl glycol (also known as BG, 2-butoxyethanol, glycol monobutyl  ether and ethylene glycol monobutyl ether, butyl cellosolve,  butoxyethanol) is a clear, colourless, oily liquid with a unique sweet  yet mild odour and has the formula C6H14O2. It is a butyl ether of  ethylene glycol and is miscible with water and common organic  solvents. It has been produced industrially for over half a century  and is used primarily as a solvent in paints and surface coatings but  also in inks and cleaning products. 

Butyl Glycol – Technical Properties 

Chemical and physical properties of butyl glycol: 

Molecular Formula: C6H14O2 / CH3(CH2)2CH2OCH2CH2OH 

Synonyms: 2-Butoxyethanol, Butyl Cellosolve, Butyl Monoether Glycol, Ethylene Glycol  Monobutyl Ether (EGBE), Butoxyethanol 

Cas Number: 111-76-2 

Molecular Mass: 118.176 g/mol1 

Exact Mass: 118.09938 g/mol 

Flashpoint: 153 °F / 67 °C 

Boiling Point: 340 °F / 171 °C 

Melting Point: -107 °F / -77 °C 

Vapour Pressure: 0.76 mm Hg at 68 ° F 

Water Solubility: ≥ 100 mg/ml (72° F) 

Density: 0.90 g/cm3 

Log P: 0.83 

How is it Produced? 

Butyl glycol is produced by reacting ethylene oxide with an alcohol such as normal  butanol (nbutanol) within a catalyst. This process is called ethoxylation. If the ratio of ethylene 

oxide to nbutanol is greater than one then di- and tri- ethylene glycol monoethers are also  produced. 

Below is the chemical equation for this reaction: 

C2H4O + C4H9OH → C4H9OC2H4OH 

World production is estimated at between 300-500 KT per annum. Butyl glycol can also be  produced through the etherification of butanol with 2-chloroethanol. 

How is it Handled, Stored and Distributed? 

Butyl glycol is classed as an irritant, therefore, great precaution and care must be taken during  the handling and distribution process. 

Butyl Glycol – Hazards 

Butyl glycol, if in contact with your eyes, skin, throat, can be harmful and cause serious irritation.  Ingestion, and skin contact, can produce headaches, nausea, and dizziness. The wearing of PPE  equipment is recommended to prevent the chances of skin content, swallowing and inhaling. 

If contact is made, it should be immediately washed out of eyes, soapy water should be used to  clean the skin and any clothing contacted should also be removed and replaced. Medical support  must be obtained in all circumstances, especially if the chemical is swallowed. 

It has a National Fire and Protection Association health rating of 3, indicating that it can cause  serious and even permanent injuries in critical conditions. A fire rating of 2 indicates that a  modest amount of high heat exposure is required for ignition to ensue; a flame or spark will easily  cause an ignition. 

Storage & Distribution 

Butyl glycol should be stored in a cool, dark place away from food and oxidants. It is transported  in carbon steel, stainless steel or teflon containers and can be moved in bulk or drums. It has a  specific gravity of 0.9 and a flashpoint of 60 °C (closed cup) and has been classified as harmful  but is not classified as dangerous for any form of transport. 

If a leak or spillage has occurred, it should be immediately isolated (up to 50 meters in a 360  angle) and the source should be eliminated (only if possible, without risk). Personal protection  equipment must be worn, specifically a respirator to filter out gases emitted from the spillage. 

The leak should be soaked up by a non-combustible material such as earth and then collected in  sealable containers. Wash away remainder with water. If it is a minor leak, then a more common  approach can be taken including the use of kitchen towel. This should then be burned away from  the spillage. The area must then be ventilated to ensure all vapours and gases are eliminated. 

How is Butyl Glycol Used? 

Butyl glycol has many uses, primarily as a solvent, in both the commercial and industrial  industries. 

Industry Uses 

Butyl glycol usage is dominated by the paint industry which consumes approximately 75 % of all  the BG produced. This is because it is a low volatility solvent and can therefore both extend the  drying times of coatings and improve their flow.

Other applications include use as a solvent in printing inks due to its high boiling point, textile  dyes and as a component of hydraulic fluids. It is also a component of drilling and cutting oils and  is a major component of Corexit 9527, which is an oil spill dispersant product. 

It is also a chemical intermediate and, as such, is a starting material in the production of butyl  glycol acetate which is, itself, an excellent solvent. It is also a starting material in the production  of plasticisers by the reaction of phthalic anhydride. 

Commercial Uses 

Butyl glycol is used regularly in most households as it is a component of many home cleaning  products. It provides excellent cleaning power for domestic cleaning products and also provides  the characteristic odour that we associate with them. It also plays the same role in some  industrial and commercial surface cleaners. 

Many other products contain butyl glycol including spray lacquers, varnishes, varnish removers,  paints, liquid soaps, degreasers, leather protectors, whiteboard cleaners, printing pastes,  enamels, cosmetics and herbicides.