NOVELTY - Producing liquid hydrocarbon mixture, comprises: (a) providing biomass-derived feedstream comprising 5-6C hydrocarbon diols; (b) contacting the feedstream with first catalyst in a reactor, where the contacting results in an acidic condensation reaction that converts feedstream to condensation products; and (c) converting at least a portion of the remaining hydroxy functional groups on the condensation products from step (b) to ether functional groups by combining the condensation products with second catalyst to produce liquid hydrocarbon mixture.    USE - The process is useful for producing a liquid hydrocarbon mixture which is useful as an additive to liquid hydrocarbon fuels (claimed).    ADVANTAGE - The process is cost effective; and has increased miscibility in liquid hydrocarbon fuels. The improved liquid hydrocarbon fuel has improved combustion properties relative to the original liquid hydrocarbon transportation fuel, where the combustion properties having increased cetane number, and/or decreased emissions of environmental pollutants during combustion.    DETAILED DESCRIPTION - Producing a liquid hydrocarbon mixture, comprises: (a) providing a biomass-derived feedstream comprising 5-6C hydrocarbon diols, (b) contacting the feedstream with a first catalyst in a reactor, where the contacting results in an acidic condensation reaction that converts at least a portion of the feedstream to condensation products, which comprise at least 10C and at least one ether functional group, and (c) converting at least a portion of the remaining hydroxy functional groups on the condensation products from step (b) to ether functional groups by combining the condensation products with a second catalyst to produce a liquid hydrocarbon mixture, where the converting takes place in the presence of an olefin and/or monofunctional alcohol. An INDEPENDENT CLAIM is also included for producing water and a liquid hydrocarbon mixture, comprising step (a) and (b) as above per se, and (c1) reducing at least a portion of the remaining hydroxy groups on the condensation products from step (b) by combining the condensation products with a second catalyst in the presence of hydrogen to produce water and a liquid hydrocarbon mixture.