摘要 |
This invention comprises a process for separating isomers of dihydroxybenzene (DHB) from a feed mixture comprising at least two of said isomers, which process comprises contacting the mixture at adsorption conditions with an adsorbent comprising a Y type zeolite cation exchanged with a cation in the group Ca, Ba or Li, thereby selectively adsorbing o-DHB (catechol), or K, thereby selectively adsorbing p-DHB (hydroquinone). In the case where all three isomers are present in the feed, a cation from the first group is used, the remainder of the feed mixture is removed from the adsorbent and o-DHB is recovered by desorption at desorption conditions with methanol. P-DHB is recovered from the remainder by adsorption with the same or other adsorbent listed above and desorption at desorption conditions with ethanol.
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