Patent ID: 8198058

Claim:
A method of producing liquid fuel comprising: (a) fermenting organic material in a fermentation mixture to a biogas comprising methane and CO 2 ; (b) converting at least a portion of the biogas to synthesis gas comprising CO and H 2 by a process comprising: (i) a CO 2 reforming reaction of CH 4 +CO 2 to 2CO+2H 2 ; and (ii) a partial oxidation reaction of CH 4 +½ O 2 to CO+2H 2 or a steam reforming reaction of CH 4 +H 2 O to CO+3H 2 ; and (c) contacting the synthesis gas with a catalyst to produce a liquid fuel product mixture comprising alcohol or diesel fuel; wherein an amount of CO 2 equal to at least 30% of the CO 2 in the biogas is converted in the CO 2 reforming reaction, and at least 30% of the CH 4 in the biogas is converted in the partial oxidation reaction or steam reforming reaction.