On the improved absorption of carbon monoxide in the ionic liquid 1-hexyl-3-methylimidazolium chlorocuprate

► Carbon monoxide recovery from the tail gas stream obtained in the production of carbon black. ► Carbon monoxide absorption via copper (I) complexation in 1-hexyl-3-methyl-imidazolium chlorocuprate. ► Enhanced the carbon monoxide absorption. ► High CO/N2 ideal separation factor.