NOVELTY - Producing a fuel, involves contacting a bio-oil containing product with at least a first zeolite thin film under conditions effective to remove oxygen containing functional groups and provide a first product.    USE - For producing a fuel, and for deoxygenating a bio-oil (claimed).    ADVANTAGE - The staged and stratified configuration of the reactor enables different catalysts to be operated at optimal temperatures, and also enables efficient energy integration, because it is possible for the entire method to be carried out in a single pipe. The use of zeolitic catalysts with multiple levels of porosity enables facile mass transfer processes to enable the entire chemical conversion process to occur in millisecond timescales. The method leads to potential breakthroughs in the production of hydrocarbon fuels from solid lignocellulosic biomass without the use of expensive molecular hydrogen via a single-stage continuous and scalable, autothermal conversion process that involves co-processing biomass with alkane and/or alcohol co-reactants over multifunctional catalysts. The methods do not require intermediate production of molecular hydrogen to deoxygenate biomass, because light alkanes can serve as hydrogen carriers for deoxygenation reactions. The methods are capable of processing solid feedstock under continuous and autothermal conditions, preferably without the necessity of conditions such as high pressures and recycling. The methods enable acid-catalyzed chain growth reactions to be coupled with metal-catalyzed exothermic reactions in a single staged and/or stratified reactor configuration for the production of hydrocarbons in a single-train chemical process, while preferably eliminating capital intensive processing steps along the way. The process involves the rapid and selective conversion of cellulosic biomass in autothermal millisecond contact time reactors by direct impingement of solids (and liquids) on a hot catalytic surface. In addition to enabling continuous char-free operation, short contact time reactors bypass the slow hydrolysis step of liquid phase processing and result in process miniaturization by more than a factor of ten.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) deoxygenating a bio-oil, involving: contacting a bio-oil containing product with at least a first zeolite thin film under conditions effective to remove oxygen containing functional groups;    (2) a multi-stage, stratified reactor comprising: an input for feed components comprising biomass feedstock and alkane and/or alcohol feedstock; a stage containing at least one metal-containing catalyst for contacting the feed components to form a bio-oil; at least one stage containing at least one zeolite thin film for contacting the bio-oil and optional intermediate products to form a fuel; and an output for the fuel formed.