NOVELTY - Forming renewable jet fuel blendstock involves: treating biomass to feedstock; fermenting with microorganism(s) to form isobutanol; dehydrating to isobutene product; oligomerizing to product comprising each of at least one 8, 12 and 16 carbon containing unsaturated oligomers; hydrogenating oligomers to renewable jet fuel blendstock having each of at least one 12 and 16 carbon containing saturated alkanes; and adjusting alkanes ratio to form renewable jet fuel blendstock that meets or exceeds ASTM D7566-10a for hydroprocessed synthesized paraffinic kerosene (SPK).    USE - For preparing renewable jet fuel blendstock, useful for preparing renewable jet fuel (claimed) for e.g. diesel, aviation and automotive industries.    ADVANTAGE - The renewable jet fuel blendstock provides improved renewable jet fuel blendstock and jet fuel blends, with costs and performance properties comparable to, or superior to existing jet fuels, and which meet or exceed the purity requirements of ASTM D7566 10a for aviation turbine fuel containing synthetic hydrocarbons. The fuel blendstock is derived from abundant biomass, using existing capital assets such as ethanol plants and typical refinery operations. Further, the method provides a clean process that enables production of jet fuel from pure compounds (e.g. isobutylene) rather than separating jet from complex mixture with many by-products (e.g. isolation from petroleum, or oligomerization of mixed monomer streams). Thus, the process provides direct production of a renewable jet fuel blendstock, with minimal production of other products, in a targeted, highly specific fashion. This provides a highly product-specific process which minimizes need for process equipment to remove and/or make use of undesired by-products typical in conventional jet production process, or in oligomerization processes which employ a wide range of monomers. The method provides renewable jet fuel blendstocks that meet military and ASTM D7566 10a blend stock requirements for renewable jet. The method adjusts the composition of a renewable jet fuel blendstock to concomitantly adjust its properties, to meet blend requirements for many jet fuels.    DETAILED DESCRIPTION - Process (P1) for preparing renewable jet fuel blendstock involves: (a) treating biomass to form a feedstock; (b) fermenting the feedstock with at least one species of microorganism to form isobutanol; (c) dehydrating at least a portion of the isobutanol obtained in step (b) to form a dehydration product comprising isobutene; (d) oligomerizing at least a portion of the dehydration product to form a product comprising at least one 8C, at least one 12C, and at least one 16C unsaturated oligomers; (e) hydrogenating at least a portion of the product of step (d) in the presence of hydrogen to form a renewable jet fuel blendstock comprising at least one 12C and at least one 16C saturated alkanes; and (f) adjusting the ratio of 12C and 16C saturated alkanes provided by step (e) to form a renewable jet fuel blendstock which meets or exceeds the requirements of ASTM D7566-10a for hydroprocessed synthesized paraffinic kerosene (SPK). INDEPENDENT CLAIMS are included for the following: (1) a renewable SPK jet fuel blendstock produced by the process (P1); (2) process (P1a) for preparing a renewable jet fuel involving: combining the renewable jet fuel blendstock prepared by the process (P1) with a conventional jet fuel blendstock, so that the renewable jet fuel meets or exceeds the requirements of ASTM D7566-10a; and (3) a renewable SPK jet fuel blendstock produced by the process (P1a), which meets or exceeds the requirements of ASTM D7566-10a.