Uses of Phenol

Phenol's combination of a reactive, activated aromatic ring and a genuinely acidic $-\text{OH}$

group makes it valuable across several quite different commercial and historical applications.

Antiseptic and disinfectant. Phenol was the first chemical antiseptic used systematically in

surgery: Joseph Lister introduced dilute phenol (then called 'carbolic acid') in the 1860s to

sterilise surgical instruments, wounds and the operating theatre itself, dramatically reducing

post-operative infection and mortality and founding the modern practice of antiseptic surgery.

Phenol kills bacteria by denaturing their proteins, disrupting the cell membrane and cellular

machinery; because concentrated phenol is corrosive to human skin and tissue, modern antiseptic and

disinfectant formulations generally use much more dilute phenol solutions, or related but gentler

phenolic derivatives (such as the chlorinated cresols used in some household disinfectants),

retaining phenol's antibacterial action while reducing its tissue-damaging side effects.

Manufacture of phenol-formaldehyde resin. Phenol reacts with formaldehyde (methanal), under

acidic or basic catalysis, in a condensation polymerisation that builds up a rigid, cross-linked

three-dimensional polymer network -- phenol-formaldehyde resin, commercially known by its

early trade name Bakelite. First commercialised in the early twentieth century, Bakelite was

the first fully synthetic plastic (as opposed to a chemically modified natural polymer) and remains

in use today for its excellent heat resistance, electrical insulating properties and rigidity, in

applications from electrical fittings and appliance handles to laminates.

Other uses. Phenol is also an important raw material for the pharmaceutical and dye

industries -- for example, it is a starting material, via salicylic acid, in the manufacture of

aspirin (acetylsalicylic acid) -- and, as noted in Section 16.12, its exhaustive nitration product, …