Methylated spirit
Encyclopedia
Denatured alcohol or methylated spirits is ethanol
that has additives to make it more poisonous or unpalatable, and thus, undrinkable. In some cases it is also dyed.
Denatured alcohol is used as a solvent
and as fuel for spirit burners and camping stoves. Because of the diversity of industrial uses for denatured alcohol, hundreds of additives and denaturing methods have been used. Traditionally, the main additive is 10% methanol
, giving rise to the term "methylated spirit." Other typical additives include isopropyl alcohol
, acetone
, methyl ethyl ketone, methyl isobutyl ketone
, and denatonium
.
Denaturing alcohol does not chemically
alter the ethanol molecule. Rather, the ethanol is mixed with other chemicals to form an undrinkable solution.
Different additives are used to make it difficult to use distillation
or other simple processes to reverse the denaturation. Methanol is commonly used both because of its boiling point being close to that of ethanol and because it is toxic. In many countries, it is also required that denatured alcohol be dye
d blue or purple with an aniline dye.
, suitable for human consumption as a drink) is usually very expensive compared to similar chemicals, being highly taxed for revenue and public health policy purposes (see sin tax
). Pure ethanol would have the same health hazards as any other high concentration alcohol. As a result, if pure ethanol were made cheaply available as a fuel or solvent, people would drink it.
Denatured alcohol provides a solution to permit legitimate use and manufacture of ethanol, whereby cheap ethanol can be made available for non-consumption use without the risk of it being converted for consumption. The process creates an ethanol-containing solution that is not suitable for drinking, but is otherwise similar to ethanol for most purposes. As a result there is no duty
on denatured alcohol in most countries, making it considerably cheaper than pure ethanol
. Consequently, its composition is tightly defined by government regulations which vary between countries.
In some countries they have more denatured alcohol to reduce alcoholism.
In the United States, small amounts of denatured alcohol are used in many consumer products such as toothpaste
where they are labeled as "SD alcohol XX", where SD stands for "specially denatured" and XX is the formula used in the denaturing process that specifies the denaturants. These formulas for denatured alcohol are found in 27 CFR part 21 of the Code of Federal Regulations
. Some of these formulas, such as SD alcohol 38-B, are designed to be unpalatable but otherwise non-poisonous; they are used in applications like mouthwashes where some amount of incidental ingestion is expected. (The specific denaturants in formulas 37 and 38-B closely resemble the active ingredients in alcohol-based mouthwashes like Listerine.)
, which can result in blindness or death if the denatured alcohol contains methanol
. This happened during Prohibition
, when the U.S. government used methanol in industrial alcohols manufactured in the United States. To help prevent this, denatonium
is often added to give the substance an extremely bitter flavor. Substances such as pyridine
help to give the mixture an unpleasant odor, and emetic (vomiting) agents such as syrup of ipecac
may also be included. In Poland
and other European countries denatured alcohol contains only substances having bitter flavor (like acetylsalicylic acid
) and odour, and does not contain methanol
or any substance of severe toxicity.
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
that has additives to make it more poisonous or unpalatable, and thus, undrinkable. In some cases it is also dyed.
Denatured alcohol is used as a solvent
Solvent
A solvent is a liquid, solid, or gas that dissolves another solid, liquid, or gaseous solute, resulting in a solution that is soluble in a certain volume of solvent at a specified temperature...
and as fuel for spirit burners and camping stoves. Because of the diversity of industrial uses for denatured alcohol, hundreds of additives and denaturing methods have been used. Traditionally, the main additive is 10% methanol
Methanol
Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...
, giving rise to the term "methylated spirit." Other typical additives include isopropyl alcohol
Isopropyl alcohol
Isopropyl alcohol is a common name for a chemical compound with the molecular formula C3H8O. It is a colorless, flammable chemical compound with a strong odor...
, acetone
Acetone
Acetone is the organic compound with the formula 2CO, a colorless, mobile, flammable liquid, the simplest example of the ketones.Acetone is miscible with water and serves as an important solvent in its own right, typically as the solvent of choice for cleaning purposes in the laboratory...
, methyl ethyl ketone, methyl isobutyl ketone
Methyl isobutyl ketone
Methyl isobutyl ketone is the organic compound with the formula 2CHCH2CCH3. This colourless liquid, a ketone, is widely used as a solvent.-Production:...
, and denatonium
Denatonium
Denatonium, usually available as denatonium benzoate and as denatonium saccharide, is the bitterest chemical compound known; with bitterness thresholds of 0.05 ppm for the benzoate and 0.01 ppm for the saccharide.It was discovered in 1958 during research on local anesthetics by Macfarlan...
.
Denaturing alcohol does not chemically
Chemical structure
A chemical structure includes molecular geometry, electronic structure and crystal structure of molecules. Molecular geometry refers to the spatial arrangement of atoms in a molecule and the chemical bonds that hold the atoms together. Molecular geometry can range from the very simple, such as...
alter the ethanol molecule. Rather, the ethanol is mixed with other chemicals to form an undrinkable solution.
Different additives are used to make it difficult to use distillation
Distillation
Distillation is a method of separating mixtures based on differences in volatilities of components in a boiling liquid mixture. Distillation is a unit operation, or a physical separation process, and not a chemical reaction....
or other simple processes to reverse the denaturation. Methanol is commonly used both because of its boiling point being close to that of ethanol and because it is toxic. In many countries, it is also required that denatured alcohol be dye
Dye
A dye is a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and requires a mordant to improve the fastness of the dye on the fiber....
d blue or purple with an aniline dye.
Purpose
Denatured alcohol is not, in itself, a preferred product—that is, it is not something which would be normally demanded if given the alternative of normal ethanol. Denatured alcohol and its manufacture are a public policy compromise. The supply and demand for denatured alcohol arises from the fact that normal alcohol (which in everyday language refers specifically to ethanolEthanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
, suitable for human consumption as a drink) is usually very expensive compared to similar chemicals, being highly taxed for revenue and public health policy purposes (see sin tax
Sin tax
A sin tax is a kind of sumptuary tax: a tax specifically levied on certain generally socially proscribed goods and services. These goods are usually alcohol and tobacco, but also include candies, soft drinks, fat foods and coffee, while services range from prostitution to...
). Pure ethanol would have the same health hazards as any other high concentration alcohol. As a result, if pure ethanol were made cheaply available as a fuel or solvent, people would drink it.
Denatured alcohol provides a solution to permit legitimate use and manufacture of ethanol, whereby cheap ethanol can be made available for non-consumption use without the risk of it being converted for consumption. The process creates an ethanol-containing solution that is not suitable for drinking, but is otherwise similar to ethanol for most purposes. As a result there is no duty
Duty (economics)
In economics, a duty is a kind of tax, often associated with customs, a payment due to the revenue of a state, levied by force of law. It is a tax on certain items purchased abroad...
on denatured alcohol in most countries, making it considerably cheaper than pure ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
. Consequently, its composition is tightly defined by government regulations which vary between countries.
In some countries they have more denatured alcohol to reduce alcoholism.
Formulations
There are several grades of denatured alcohol, but the denaturants used are generally similar. As an example, the formulation for completely denatured alcohol, according to British regulations must be:Completely denatured alcohol must be made in accordance with the following formulation: with every 90 parts by volume of alcohol mix 9.5 parts by volume of wood naphtha or a substitute for wood naphtha
and 0.5 parts by volume of crude pyridinePyridinePyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one C-H group replaced by a nitrogen atom...
, and to the resulting mixture add mineral naphtha (petroleum oil) in the proportion of 3.75 litres to every 1000 litres of the mixture and synthetic organic dyestuff (methyl violetMethyl violetMethyl violet is a family of organic compounds that are mainly used as dyes. Depending on the amount of attached methyl groups, the color of the dye can be altered. Its main use is as a purple dye for textiles and to give deep violet colors in paint and ink...
) in the proportion of 1.5 grams to every 1000 litres of the mixture.
Uses
Denatured alcohol has a variety of common uses:- As a fuel for marine and ultra-light camping (backpacking)Ultralight backpackingUltralight backpacking is a style of backpacking that emphasizes carrying the lightest and simplest kit safely possible for a given trip. Base pack weight is reduced as much as safely possible, though reduction of the weight of...
stovesPortable stoveA portable stove is a cooking stove specially designed to be portable and lightweight, as for camping or picnicking, or for use in remote locations where an easily transportable means of cooking or heating is needed...
. It is inexpensive, may be extinguished with water, and can be transported without special containers. However, safety concerns do arise from the near-colourless flame with which alcohol burns. A jellied and dyed form is used in the SternoSternoSterno is a fuel made from denatured and jellied alcohol. It is designed to be burned directly from its can. Its primary uses are in the food service industry for buffet heating and in the home for fondue and as a chafing fuel for heating chafing dishes...
brand fuel "Canned Heat", and is meant to be ignited and used in the container. - To pre-heat the vaporizing tubes on a wickless paraffinParaffinIn chemistry, paraffin is a term that can be used synonymously with "alkane", indicating hydrocarbons with the general formula CnH2n+2. Paraffin wax refers to a mixture of alkanes that falls within the 20 ≤ n ≤ 40 range; they are found in the solid state at room temperature and begin to enter the...
stove such as a Primus stovePrimus stoveThe Primus stove, the first pressurized-burner kerosene stove, was developed in 1892 by Frans Wilhelm Lindqvist, a factory mechanic in Stockholm, Sweden. The stove was based on the design of the hand-held blowtorch; Lindqvist’s patent covered the burner, which was turned upward on the stove... - As a sanding aid, as the alcohol helps to more easily remove excess dust because it does not open the wood grain the way that water does.
- As a mealybugMealybugMealybugs are insects in the family Pseudococcidae, unarmored scale insects found in moist, warm climates. They are considered pests as they feed on plant juices of greenhouse plants, house plants and subtropical trees and also acts as a vector for several plant diseases.-Distribution:Mealybugs...
exterminator. - As a cleaning aid in removing inkInkInk is a liquid or paste that contains pigments and/or dyes and is used to color a surface to produce an image, text, or design. Ink is used for drawing and/or writing with a pen, brush, or quill...
stains from upholsteryUpholsteryUpholstery is the work of providing furniture, especially seats, with padding, springs, webbing, and fabric or leather covers. The word upholstery comes from the Middle English word upholder, which referred to a tradesman who held up his goods. The term is equally applicable to domestic,...
or clothes. - As a cleaner in daily housekeeping
- To disinfect skin prior to an injection or minor surgery, such as draining a blister (also see rubbing alcoholRubbing alcoholRubbing alcohol, USP / B.P. is a liquid prepared and used primarily for topical application. It is prepared from a special denatured alcohol solution and contains 97.5-100% by volume of pure, concentrated ethanol or isopropyl alcohol...
). - It is often used as an antisepticAntisepticAntiseptics are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction...
for minor wounds, although this practice is harmful and counterproductive, since it kills skin cells, and the dead tissue provides a food source for bacteria (since the wound will not remain completely sterile). - As a solvent in shellacShellacShellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes , which are dissolved in ethyl alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish...
and shellac-based products. - As an excipientExcipientAn excipient is generally a pharmacologically inactive substance used as a carrier for the active ingredients of a medication. In many cases, an "active" substance may not be easily administered and absorbed by the human body; in such cases the substance in question may be dissolved into or...
in a number of pharmaceutical products for oral and topical use. - As a less expensive alternative to pure ethanolEthanolEthanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
in preserving biological specimens. - As a less toxic alternative to methanol in the production of biodieselBiodieselBiodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl esters. Biodiesel is typically made by chemically reacting lipids with an alcohol....
fuel. Biodiesel produced using ethanol is properly called fatty acid ethyl ester, whereas biodiesel from methanol is properly referred to as fatty acid methyl ester. - As a germicide in the removal of fungusFungusA fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
from skin and coldsoreHerpes simplexHerpes simplex is a viral disease caused by both Herpes simplex virus type 1 and type 2 . Infection with the herpes virus is categorized into one of several distinct disorders based on the site of infection. Oral herpes, the visible symptoms of which are colloquially called cold sores or fever...
treatment. - For maintenance of wicks in kerosene heaterKerosene heaterA kerosene heater, also known as a paraffin heater, is a portable, unvented, kerosene-fueled, space-heating device. In the United States they are used mainly for supplemental heat or as a source of emergency heat during a power outage. In some countries, particularly in Japan, they are used as...
s and lampKerosene lampThe kerosene lamp is a type of lighting device that uses kerosene as a fuel. This article refers to kerosene lamps that have a wick and a tall glass chimney. Kerosene lanterns that have a wick and a glass globe are related to kerosene lamps and are included here as well...
s to remove water contaminants and restore the capillary action of the wick. As a wick cleaner and a kerosene additive, adding approx. 1 teaspoon denatured alcohol per gallon of kerosene. - As a fuel for older toy steam engines which used a wick type or vapourising burner.
- Window washing
In the United States, small amounts of denatured alcohol are used in many consumer products such as toothpaste
Toothpaste
Toothpaste is a paste or gel dentifrice used with a toothbrush as an accessory to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it serves as an abrasive that aids in removing the dental plaque and food from the teeth, assists in suppressing...
where they are labeled as "SD alcohol XX", where SD stands for "specially denatured" and XX is the formula used in the denaturing process that specifies the denaturants. These formulas for denatured alcohol are found in 27 CFR part 21 of the Code of Federal Regulations
Code of Federal Regulations
The Code of Federal Regulations is the codification of the general and permanent rules and regulations published in the Federal Register by the executive departments and agencies of the Federal Government of the United States.The CFR is published by the Office of the Federal Register, an agency...
. Some of these formulas, such as SD alcohol 38-B, are designed to be unpalatable but otherwise non-poisonous; they are used in applications like mouthwashes where some amount of incidental ingestion is expected. (The specific denaturants in formulas 37 and 38-B closely resemble the active ingredients in alcohol-based mouthwashes like Listerine.)
Consumption and toxicity
Despite its poisonous nature, denatured alcohol is sometimes consumed as a surrogate alcoholSurrogate alcohol
Surrogate alcohol is a term for any substance containing ethanol that is consumed but is not meant for human consumption. Most people turn to these as a last resort either out of desperation or being unable to afford consumable alcoholic beverages....
, which can result in blindness or death if the denatured alcohol contains methanol
Methanol
Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...
. This happened during Prohibition
Prohibition
Prohibition of alcohol, often referred to simply as prohibition, is the practice of prohibiting the manufacture, transportation, import, export, sale, and consumption of alcohol and alcoholic beverages. The term can also apply to the periods in the histories of the countries during which the...
, when the U.S. government used methanol in industrial alcohols manufactured in the United States. To help prevent this, denatonium
Denatonium
Denatonium, usually available as denatonium benzoate and as denatonium saccharide, is the bitterest chemical compound known; with bitterness thresholds of 0.05 ppm for the benzoate and 0.01 ppm for the saccharide.It was discovered in 1958 during research on local anesthetics by Macfarlan...
is often added to give the substance an extremely bitter flavor. Substances such as pyridine
Pyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one C-H group replaced by a nitrogen atom...
help to give the mixture an unpleasant odor, and emetic (vomiting) agents such as syrup of ipecac
Syrup of ipecac
Syrup of ipecac , commonly referred to as ipecac, is derived from the dried rhizome and roots of the ipecacuanha plant, and is a well known emetic .-Preparation:...
may also be included. In Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
and other European countries denatured alcohol contains only substances having bitter flavor (like acetylsalicylic acid
Aspirin
Aspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...
) and odour, and does not contain methanol
Methanol
Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...
or any substance of severe toxicity.
External links
- 27 CFR 20, regulations relating to denatured alcohol in the United States
- Specifications and licensing of methylated spirits in the United Kingdom
- European Community COMMISSION REGULATION (EC) No 3199/93 on the mutual recognition of procedures for the complete denaturing of alcohol for the purposes of exemption from excise duty Pdf