Methanol: Properties and Applications

What is methanol and how is it produced?

Methanol (CH₃OH) is the simplest alcohol, produced industrially via catalytic hydrogenation of carbon monoxide or carbon dioxide over copper-zinc oxide catalysts. It is a key feedstock in the chemical industry, used in the synthesis of formaldehyde, acetic acid, and other derivatives. In laboratories, it serves as a solvent for chromatography, sample preservation, and cleaning. Its low boiling point (64.7 °C) and high solubility in water make it ideal for many applications, though its toxicity necessitates strict safety protocols.

Why is methanol hazardous in laboratory and industrial environments?

Methanol is highly toxic, with a lethal dose in humans as low as 30 mL when ingested. It is metabolised to formaldehyde and formic acid, causing metabolic acidosis, visual impairment, and potentially death. Exposure can occur via inhalation, ingestion, or dermal absorption. Safety measures include use of fume hoods, personal protective equipment (PPE), and proper storage in sealed, labelled containers. Regulatory frameworks such as GHS, REACH, and TSCA govern its handling, and safety data sheets (SDS) must be accessible. In the UK, compliance with Health and Safety Executive (HSE) guidelines is mandatory.

What are the regulatory and quality standards for methanol?

High-purity methanol used in pharmaceuticals and biotechnology must meet specifications such as USP, EP, and BP. Analytical-grade methanol is assessed via HPLC, GC-MS, and NMR to ensure low levels of impurities like water, formaldehyde, and ethanol. Certificates of analysis (CoA) are required for traceability. Methanol is classified under ISO 14001 and ISO 9001 for environmental and quality management in production and supply chains.

Related concepts

Methanol is often confused with ethanol (ethyl alcohol), but differs significantly in toxicity and industrial use. It is also used in fuel cells and as a denaturant in ethanol. Proper disposal must follow local environmental regulations to prevent contamination.