What’s The Difference Between White Spirit and Methylated Spirit?

by Kate Onissiphorou

The main difference between white spirit and methylated spirit is their respective chemical basis or source. The former is a solvent derived from petroleum, while the latter is a solvent derived from alcohol.

On its own, ethanol or ethyl alcohol is drinkable in very small quantities (and we wouldn’t recommend it, certainly not neat), but adding methanol makes it highly poisonous. To deter people from drinking methylated spirit – either deliberately or accidentally – a dye and bittering agent are added.  

White spirit is also known by other names, including mineral spirit, mineral turpentine, petroleum spirit, and turpentine substitute. It’s a mixture of various aliphatic hydrocarbons and is mainly used as a solvent and paint thinner.

What is methylated spirit used for?

Methylated spirit – otherwise known as denatured alcohol – is used as a solvent in various industries. Unlike normal ethanol, it’s made undrinkable to avoid the high taxes levied on alcohol that’s intended for consumption. 

Specific uses of methylated spirits

Although methylated spirit is primarily used as a solvent, it does have other applications. Some of the specific uses of methylated spirits include the following:

  • Fuel for laboratory alcohol lamps Person holding a match in the flame of an alcohol burner lamp
  • Preservative for biological specimens
  • Paint thinner or paint remover
  • Cleaning agent for hard surfaces like marble floors
  • Disinfectant for medical equipment
  • An insecticide for plants. 

Why are dye and bittering agents added to methylated spirits?

Methylated spirit is ethyl alcohol or ethanol that contains about 10% methanol, which is why it’s called ‘methylated’ spirit. 

As we’ve already discussed, ethanol is the only alcohol that’s safe for consumption; it’s present in wine, beer, and various other alcoholic beverages. However, adding methanol makes it poisonous and unsafe to drink.

The addition of methanol does not significantly change the chemical and physical properties of ethanol. In fact, it has the same taste and appearance as drinkable ethanol. It’s for this reason that manufacturers add a dye and bittering agent.

A violet dye is typically added in a methylated spirit solution to make it easily identifiable. A bittering agent such as denatonium benzoate (C28H34N2O3) is also added to deter people and animals from drinking it. This compound is so bitter that only very small amounts are added.

Using methylated spirits instead of white spirits

As a paint solvent, methylated spirit and white spirit are typically used interchangeably. Both are effective in thinning oil- and hydrocarbon-based paints, as well as cleaning brushes coated with dry and hardened paint. A can of paint thinner next to a wall, with a painter removing residue from the wall in preparation for painting.

Although methylated spirits and white spirits both make a suitable paint thinner and paint brush cleaner, methylated spirits evaporate much faster. Since methylated spirits are almost pure alcohol, they have relatively high vapour pressure and volatility. They’re also less viscous than white spirits.

Before cleaning a brush with methylated spirit, try to remove as much paint as possible from the brush. Next, pour some methylated spirit into a suitably-sized old mug or empty can. You don’t need much, but if the paint has already hardened, you may have to immerse the entire brush to allow the methylated spirit to dissolve the paint. Let it settle for a while. You may need to wait for several hours if the paint has hardened.

Finally, swirl the brush and wash it off with a new batch of methylated spirit. You may need to repeat the process until the liquid becomes clear. You can then switch to soap and hot water to complete the cleaning process.  

Specific uses of white spirits

White spirit is commonly used as a paint thinner and paint brush cleaner. However, it also has various other household and industrial applications, which include:

  • Solvent for paints, varnishes, printing inks, and adhesives
  • Industrial cleaning agent
  • Degreasing agent to remove dirty machine grease and gunk
  • Extracting substances
  • Home dry cleaning fluid 

In the UK, white spirit is also popularly known as a turpentine substitute. Its other names are Stoddard solvent and mineral spirit. Depending on the exact blend of hydrocarbons, white spirit is not as toxic as methylated spirit but, of course, it’s still unsafe to drink.

Where to buy methylated spirits

You can purchase methylated spirits in your local DIY or hardware shop. However, if you want to order in bulk or if you need it for industrial purposes as a business, you can directly buy methylated spirits from a chemical manufacturer or large-scale distributor. ReAgent's methylated spirit

Visit our online shop today to buy industrial methylated spirit from one of the UK’s leading chemical suppliers.

Original post: What’s The Difference Between White Spirit and Methylated Spirit?. No Republication or Redistribution allowed without written consent. Contact ReAgent Chemicals for more information.

Disclaimer

The blog on chemicals.co.uk and everything published on it is provided as an information resource only. The blog, its authors and affiliates accept no responsibility for any accident, injury or damage caused in part or directly from following the information provided on this website. We do not recommend using any chemical without first consulting the Material Safety Data Sheet which can be obtained from the manufacturer and following the safety advice and precautions on the product label. If you are in any doubt about health and safety issues please consult the Health & Safety Executive (HSE).