초록 ▼

The present invention relates to a cyclic process for the preparation of ethyl tert.-alkyl ethers by the reaction of an alcohol, such as ethanol, with an iso-olefin such as isobutylene or isoamylene wherein an effluent from the reaction zone is first separated in a distillation column to provide an

The present invention relates to a cyclic process for the preparation of ethyl tert.-alkyl ethers by the reaction of an alcohol, such as ethanol, with an iso-olefin such as isobutylene or isoamylene wherein an effluent from the reaction zone is first separated in a distillation column to provide an overhead effluent stream and a bottoms effluent stream comprising ethyl tert.-alkyl ether and unreacted ethanol, and the ether product is passed to an adsorption zone to remove the unreacted ethanol. When the reaction occurs in the presence of water, a tert. alcohol (e.g., TBA or TAA) is produced and, if returned to the reaction zone, the tertiary alcohol builds up in the process and reduces efficiency. An adsorbent selected from the group consisting of zeolite 13X, silica-bonded silicalite, an alkali-exchanged zeolite with an MFI structure having a silica/alumina ratio greater than 20 and mixtures thereof is employed in an adsorption zone to remove the unreacted ethanol from the ether product to provide ether product essentially free of ethanol and comprising the tertiary alcohol. Thus, the tertiary alcohol is removed with the ether product as a high octane, oxygenate blending component for reformulated gasoline with a low vapor pressure. The invention is useful in recovering unreacted ethanol from the other product stream and returning the unreacted ethanol to the reaction zone without returning TBA. The invention prevents the build-up of tertiary alcohol in the unreacted ethanol stream which adversely affects the operation of the reaction zone and reduces catalyst stability.

대표청구항 ▼

A process for the separation of ethanol from a mixture thereof, said mixture comprising ethanol, tertiary alcohol, and an ethyl tert. alkyl ether, said process comprising: a) passing said mixture to an adsorption zone containing an adsorbent for the adsorption of ethanol to provide an effluent strea

A process for the separation of ethanol from a mixture thereof, said mixture comprising ethanol, tertiary alcohol, and an ethyl tert. alkyl ether, said process comprising: a) passing said mixture to an adsorption zone containing an adsorbent for the adsorption of ethanol to provide an effluent stream essentially free of ethanol, said effluent stream comprising ethyl tert. alkyl ether and said tertiary alcohol; and b) regenerating said adsorbent to recover said ethanol.