Manufacture of SOAPY detergents

Boil

Vegetable oil is boiled with a concentrated sodium hydroxide solution

saponification

The ester in the vegetable oil breaks down and releases an organic acid and an alcohol

Neutralisation

The organic acid is immediately neutralised by the sodium hydroxide solution to form a sodium salt of the organic acid

Salting out

The soap is precipitated by adding in concentrated sodium chloride solution which lowers the solubity of the soap and causes it to float on top

Compression

The solid soap is removed, compressed and then cut into blocks

Examples

Sodium palmate

sodium stearate

potassium palmate

potassium stearate

Environmental impact

When poorly disposed, detergents may end up in waterbodies where they may lead to eutrophication and death of aquatic wildlife

Mitigation

Through treating water to ensure cleanliness