NOVELTY - Continuous process for simultaneous hydration of an olefin feedstream which contains principally mixed butenes, and includes at least two butene isomers to produce mixed butanols, comprises: (a) providing a reaction vessel containing water, an acid hydration catalyst and liquefied olefins containing butene isomers; (b) promoting the hydration of the butene isomers; (c) removing the olefins containing butene isomers; (d) separating the mixed butanols; (e) recovering the mixed butanol product stream; and (f) returning the lean olefin containing butene isomer stream to the reaction vessel.    USE - The processes are useful for simultaneous hydration of olefin feedstream which contains principally mixed butenes, and includes at least two butene isomers to produce mixed butanols; and for producing mixed alcohols from liquid butene feedstream that contains at least two butene isomers. The reaction product or composition is useful as neat fuel or fuel additive (all claimed).    ADVANTAGE - The invention provides efficient and cost-effective process for producing mixed butanols by hydration, or for producing mixed butenes from readily available butene sources to meet the current and foreseeable increased future demands for these products on a worldwide basis.    DETAILED DESCRIPTION - Continuous process for simultaneous hydration of an olefin feedstream which contains principally mixed butenes, and includes at least two butene isomers to produce mixed butanols, comprises: (a) providing a reaction vessel containing water, an acid hydration catalyst and liquefied olefins containing butene isomers; (b) promoting the hydration of the butene isomers to form mixed butanols and the extraction of the butanols from the aqueous phase by the butene isomers in the liquid olefin phase; (c) removing the olefins containing butene isomers enriched with mixed butanol reaction products extracted from the first aqueous phase; (d) separating the mixed butanols from the olefins containing butene isomers to form a mixed butanol product stream and a lean olefin stream; (e) recovering the mixed butanol product stream; and (f) returning the lean olefin containing butene isomer stream to the reaction vessel. INDEPENDENT CLAIMS are:    (1) a reaction product produced by the process;    (2) a composition comprising the products for use as a neat fuel or a fuel additive; and    (3) a process for producing mixed alcohols from a liquid butene feedstream that contains at least two butene isomers, comprising: (a) providing a reaction vessel containing a phase-separated mixture of water containing a soluble acid hydration catalyst as a first aqueous phase and liquefied butene isomers as a second organic phase; (b) introducing the second organic phase into the first aqueous phase under conditions favorable to hydration of the butene isomers, to form mixed butanols; (c) removing a portion of the butene isomers enriched with mixed butanols extracted from the first aqueous phase from the reaction vessel; (d) separating the mixed butanols from the butene isomers to form a mixed butanol product stream and a lean butene isomer stream; (e) recovering the mixed butanol product stream; and (f) returning the lean butene isomer stream to the reaction vessel; or a process for producing mixed alcohols from a liquid butene feedstream that contains at least two butane isomers, comprising: (a) providing a fixed bed reactor containing a hydration catalyst; (b) introducing the liquid butene feedstream and water into the fixed bed reactor and into contact with the hydration catalyst under conditions favorable to hydration of the butene isomers, to form mixed butanols; (c) recovering the butene isomers enriched with mixed butanols from the fixed bed reactor; (d) separating the mixed butanols from the butene isomers to forma mixed butanol product stream and a lean butene isomer stream; (e) recovering the mixed butanol product stream; and (f) returning the lean butene isomer stream to the fixed bed reactor.