Patent ID: 8691538

Claim:
A method of making at least one chemical product comprising the steps of: a) exposing a biofilm comprising a photosynthetic, autofermentative microorganism to light, wherein the biofilm is disposed on a support substrate that is disposed in channels of a biofilm photobioreactor and wherein the support substrate is fixed to inner surfaces of the biofilm photobioreactor, b) alternately flowing a gas comprising carbon dioxide through the channels and at least partially filling the channels with a first liquid, wherein the gas comprising carbon dioxide and the first liquid contact the biofilm and the photosynthetic, autofermentative microorganism makes at least one metabolic intermediate compound by photosynthesis; c) depriving the biofilm of light; and d) at least partially filling the channels of the biofilm photobioreactor with a second liquid, wherein the second liquid contacts the biofilm, the photosynthetic, autofermentative microorganism converts the at least one metabolic intermediate compound into the at least one chemical product and the at least one chemical product enters the second liquid.