The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 15, 1997
Filed:
Apr. 26, 1995
Henry Rastelli, New Fairfield, CT (US);
Carmen M Yon, Carmel, NY (US);
Stanley J Frey, Palatine, IL (US);
UOP, Des Plaines, IL (US);
Abstract
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.