Coffey was born in Calais, France in 1780 to Irish parents and was educated at Trinity College, Dublin. He entered the excise service around 1799–1800 as a gauger. He married Susanna Logie in 1808, and they had a son, also named Aeneas, who may have been their only child.
According to British customs and excise records, he was appointed sub-commissioner of Inland Excise and Taxes for the district of Drogheda in 1813, and was eventually promoted to Inspector General of Excise in Ireland. He resigned from the service at his own request in 1824.
He patented a single column still in 1830, enhancing the original design for the column still by Robert Stein in 1826. His column still became widely popular and is known as the "Coffey still" or "Patent Still". Early Coffey stills produced spirits of about 60% or somewhat higher alcohol by volume concentration. Modern versions can achieve much higher alcohol concentrations – approaching 95.6% alcohol. As alcohol forms an azeotrope with water at this concentration, it is impossible to achieve higher purity alcohol by distillation alone.
On his retirement from service, Coffey went into the distilling business and for a short time ran the Dock Distillery in Grand Canal Street, Dublin. The development of the Coffey still made distillation for beverage and other purposes much more economical.
- Ó Cobhthaigh – Gaelic-Irish surname now generally Anglicised as Coffey or Coffee.
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