TECHNOLOGY FOCUS - BIOLOGY - Preferred Method: In the method, the fermentation in step (a) is conducted in an anaerobic reactor in the absence of oxygen. The metabolites of acetone, butanol and ethanol from step (a) are stripped from the fermentation when concentrations over 2-3 wt.% are obtained, to avoid any poisoning of the microorganism. The trimerizing of acetone in step (d) or step (h3) is carried out in the gas phase by passing acetone in contact with a catalyst containing niobium oxide at elevated temperatures. The dimerization of acetone in step (c) or step (g3) is carried out in a catalytic reaction to yield isopentane. The dimerization of acetone in step (c) or step (g3) is carried out in a gas phase catalytic reaction. The trimerization of acetone in step (d) or step (h3) is carried out with a catalyst of niobium oxide on a base of alumina washcoat on calcined aluminized stainless steel corrugated film; a catalyst of niobium oxide on a base of alumina beads; a catalyst of niobium oxide on silica gel; a catalyst of manganese nitrate on alumina beads; a catalyst of manganese nitrate on silica gel; a catalyst of manganese nitrate on a base of alumina washcoat on calcined aluminized stainless steel corrugated film. The ethanol (E1) is produced from a plant material involves providing saccharophagus degradans, strain 2-40; growing the saccharophagus degradans, strain 2-40 in a first portion of the plant material; harvesting protein from saccharophagus degradans, strain 2-40, and mixing the protein with a second portion of the plant material and yeast in an aqueous mixture, by producing ethanol, where the aqueous mixture contains salt (at least 1%) and/or salt (at most 10%). The ethanol (E2) is converted to acetone in the presence of iron oxide catalysts; in the presence of zinc oxide-calcium oxide catalysts and water vapor; and by a gas phase catalystic reaction at elevated temperatures. Preferred Components: The biomasses are selected from sugars, celluloses, lignins, starches, and lignocelluloses; or hard woods, grasses, corn stover, sorghum, corn fiber, and oat hulls, which are pretreated with enzymes or strong acids to break any hemicellulose chains into their sugar monomers.    TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Components: The microorganisms are at least one selected from Morella thermoaceticum, thermoanaerobacter kivui, Morella thermoacetica, Morella thermoautotrophica, Moorella thermoaeticum, moorella thermoautotrophicum, thermoanaerobacter thermosaccharolyticum, moorella thermoaceticum, and saccharophagus degradans, strain 2-40. The microorganism is clostridium or its variants. EXAMPLE - No suitable example given.