The growing gap between petroleum production and demand, mounting environmental concerns, and increasing fuel prices have stimulated intense interest in research and development (R&D) of alternative fuels, both synthetic and bio-derived. Currently, the most technically defined thermochemical route for producing alternative fuels from lignocellulosic biomass involves gasification/reforming of biomass to produce syngas (carbon monoxide [CO] + hydrogen [H 2 ]), followed by syngas cleaning, Fischer-Tropsch synthesis (FTS) or mixed alcohol synthesis, and some product upgrading via hydroprocessing or separation. A detailed techno-economic analysis of this type of process has recently been published [1] and it highlights the need for technical breakthroughs and technology demonstration for gas cleanup and fuel synthesis. The latter two technical barrier areas contribute 40% of the total thermochemical ethanol cost and 70% of the production cost, if feedstock costs are factored out. Developing and validating technologies that reduce the capital and operating costs of these unit operations will greatly reduce the risk for commercializing integrated biomass gasification/fuel synthesis processes for biofuel production. Project DescriptionThe objective of the project was to develop and implement a two-stage process for deep cleaning of raw biomass gasifier syngas using a dual fluidized bed reactor system called "Therminator" operating at 600-700ºC (1112-1292ºF) in the first stage. A novel attrition-resistant triple function catalyst system used in the Therminator simultaneously reforms, cracks, or removes tar, ammonia (NH 3 ) and hydrogen sulfide (H 2 S) from the raw biomass-derived syngas. The catalyst is circulated between the coupled fluidized-bed reactors (absorber and regenerator). The gas leaving the Therminator will be cooled and filtered using a candle filter system at 200 to 300ºC (392-576ºF). The filtered gas can be further cleaned in a second (polishing) stage consisting of a fixed-bed of a mixed-metal oxide sorbent-catalyst to reduce the tar, ammonia, and H 2 S so that the syngas can be directly used in a downstream process for synthesis of liquid fuels and chemicals.The proposed Therminator technology is designed to be a low cost (capital and operating) option for removing tars, ammonia, and sulfur from biomass-derived syngas for use in a mixed alcohol catalytic synthesis process to produce cost-competitive biofuels. The project goals were to develop 1) a trifunctional catalyst system for cracking or reforming tars, dissociating ammonia, and removing sulfur to specified target levels, 2) a circulating, continuously regenerating reactor design to maximize catalyst performance and lifetime, and 3) test the skid-mounted Therminator with inert flows and biomass-derived syngas. The revised work plan will be carried out in four tasks.The Project was divided up into four main technical tasks as described in the following: Task 1. Laboratory Testing and Catalyst Scale-up Laboratory-scale catalyst testing at Clemson Uni...