What is Iso Propanol?
Isopropanol (also known as 2-propanol, Isopropyl alcohol, Propan-2-ol or rubbing alcohol) is a structural isomer of propanol (propyl alcohol) and has the molecular formula of C3H8O. It is a clear, colourless and volatile liquid and has a distinctive strong alcohol or acetone-like odour. This solvent is highly flammable, with a flashpoint of around 11 – 13° C. Isopropanol is soluble in most solvents, including water.
Isopropanol is a common sterilising agent with antibacterial properties which is used in many cleaning applications including hand wipes, disinfectants, hand sanitisers and spray-in-air or ultrasonic products. It also has effective uses in hospitals and medical centres including eliminating skin pathogens.
Solutions of Isopropanol of around 70% are the most effective at disinfection and sterilisation (with a 10 – 40% solution of purified water). This is because when concentrations of alcohol drop below 50%, its sterilising properties decrease at a considerable rate and when this percentage rises say to 90%, these properties do not increase.
Isopropanol and propyl alcohol (1-propanol) are structural isomers of each other and have similar molecules, the difference being their -OH is attached at a different location. It is miscible in water (infinitely), ether, chloroform, acetone and alcohol and chloroform and insoluble in salt solutions.
Technical properties of Isopropanol:
Molecular Formula: C3H8O, CH3CHOHCH3, (CH3)2CHOH
Molecular weight: 60.1 g/mol
Exact Mass: 60.057515 g/mol
Flashpoint: 53°F / 11.7°C
Boiling Point: 180.5°F / 82.3°C
Melting Point: -127.3°F / -89.5°C
Density: approximately 6.5 Ib / gal
Log P: 0.16
Inhalation of Isopropanol can cause irritation of and burning sensations in the mouth, throat, eyes and nose. Ingestion can lead to drowsiness, dizziness, increased heart rate, stomach upsets and, in more severe cases, heart problems. Isopropanol is also known to easily absorb through the skin, therefore skin contact should be avoided using protective clothing when handling.
How is Isopropanol Produced?
Isopropanol is chemically manufactured using several commercial methods, direct and indirect hydration.
The direct method (and the more modern adaption) of manufacturing is by reacting very high-quality propene (90-99%) with water with an acidic catalyst, which removes the requirement of sulphuric acid. The two are heated and the vapour produced flows through a reactor which contains sulphonated polystyrene cation ion exchange resins.
The indirect method is a two-step process; step one is reacting propene and sulphuric acid to form sulphate esters and the second step is the hydrolysis of sulphate esters into isopropanol. Separate reactors are used for the two different steps and, unlike the direct method, this process can use a lower quality grade of propene.
In both the above methods, the mixture of water and by-products need to go through a distillation process to separate out the isopropanol (around 90% purity).
How is Isopropanol Stored and Distributed?
Isopropanol should be stored in an air-tight storage unit/container in a cool, dry place at room temperature (avoid preserving in hot environments). The environment should be well ventilated, and it must be kept away from oxidising agents. Isopropanol should also be protected from direct sunlight, heat and sparks or open flames as it very flammable. Containers such as iso tanks made of stainless steel, aluminium or carbon steel are suitable storage units.
A solvent stockist would have a bulk petrochemical storage facility to maintain the product.
It is advised that eye protection should be worn at all times when handling isopropanol, if any clothing becomes soaked in the chemical it should be removed immediately and not worn again until clean.
A bulk solvent exporter would normally distribute this solvent in bulk vessels or tank trucks. For transportation purposes, isopropanol is classed as a flammable liquid with a fire hazard rating of 3. A full bulk chemical distributor would export the solvent throughout regions such as the UK, Europe, Africa and America. This product is a packing group 2.
What is Isopropanol Used For?
Isopropanol has a wide range of uses as both an intermediate and a solvent in an array of industries, most popularly in the pharmaceutical but also in the automotive industries.
Isopropanol is used as a solvent and cleaning fluid as it is non-toxic compared to other alternatives, for example in consumer uses such as paints, thinners for wood furnishings, inks, dye solutions, cosmetics and toiletries (lotions, body oils, polishes, shampoos, hair sprays) lubricants, greases, glasses cleaners, and disinfectants.
Small amounts of this chemical are, in fact, naturally produced by gut microbial flora.
Isopropanol is used as a chemical intermediate in the manufacture of acetone and its by-products through the process of oxidisation. Other applications include esterification to produce isopropyl acetate and reacting with aluminium metal and titanium tetrachloride to form titanium and aluminium isopropoxides.
As stated previously, it is an extremely effective steriliser when mixed with a 70% concentration of alcohol and a 10 – 40% solution of purified water, which is why it is found in disinfectant products for homes, in rubbing alcohol, hand sanitisers, care products, household cleaning products and personal care products. Isopropanol is also used for medical/pharmaceutical applications such as local anaesthetics, laboratory chemicals and bathing solutions. Additionally, it can be used as a biological specimen preservative with a solution mixture of around 90%.
Industry uses of isopropanol include anti-freeze products, adhesives, coating additives and paints. It also plays an important role in making the water component of petrol more soluble so that it does not freeze.