Separation and purification of hydroquinone from crude mixtures thereof

摘要

Separation and purification of hydroquinone from crude mixtures thereof essentially containing hydroquinone in combination with very small amounts of impurities including resorcinol and pyrogallol, include a topping distillation allowing the resorcinol to be removed as the distillation top product, and allowing a crude mixture essentially containing hydroquinone and the heavy impurities to be recovered at the column bottom, such mixture then being subjected to a bottoming distillation which allows the pyrogallol to be removed at the column bottom and allows hydroquinone in a purified form to be recovered at the column top.