Method for producing higher linear alkanes

A method of producing linear alkanes comprising 7 to 28 carbon atoms, from ethanol and/or linear alkanoic acids comprising 2 to 5 carbon atoms, the method comprising

• (a) contacting ethanol and/or a linear alkanoic acid comprising 2 to 5 carbon atoms or any salts thereof with at least one microorganism capable of carrying out two-carbon chain elongation to produce as an intermediate a linear alkanoic acid comprising 4 to 7 carbon atoms and/or a salt thereof and/or an ester thereof;
• (b) extracting the intermediate, its salt and/or ester thereof from (a) using at least one extractant, wherein the extractant comprises at least one alkyl-phosphine oxide and optionally at least one alkane comprising at least 12 carbon atoms;
• or at least one trialkylamine and at least one alkane comprising at least 12 carbon atoms;
• or a branched higher alcohol like 2 octyl-dodecanol;
• (c) contacting the extracted intermediate and/or ester thereof from (b) and optionally a further linear alkanoic acid comprising 1 to 22 carbon atoms with at least one ketonization catalyst to a linear alkanone comprising 7 to 28 carbon atoms;
• (d) contacting the linear alkanone comprising 7 to 28 carbon atoms from step (c) with at least one hydrogenation metal catalyst for catalytic hydrogenation of the linear alkanone comprising 7 to 28 carbon atoms to a corresponding secondary linear alkanol comprising 7 to 28 carbon atoms;
• (e) dehydration of the secondary linear alkanol comprising 7 to 28 carbon atoms in the presence of an acidic heterogeneous catalyst to form a corresponding linear alkene comprising 7 to 28 carbon atoms;
• and
• (f) contacting the linear alkene comprising 7 to 28 carbon atoms obtained in step (e) with at least one hydrogenation metal catalyst for catalytic hydrogenation to a corresponding secondary linear alkane comprising 7 to 28 carbon atoms;
• or combining step (e) and (f) into one single step using a catalyst or catalyst mixture providing dehydrating and hydrogenating properties, thus hydrogenolysing the secondary linear alkanol comprising 7 to 28 carbon atoms obtained in step (d) directly to the corresponding linear alkane comprising 7 to 28 carbon atoms.