(225b) Integration of Fermentation and Transesterification Industrial Scale Processes in the Lower Mississippi River Corridor

The rising price of natural gas and high emission rate of greenhouse gases from fossil fuels open new areas of research for sustainable alternatives. A wide variety of industrial chemicals are produced from petroleum based feedstock, which can be produced from biomass feedstock. Sustainable costs are included with economic and environmental costs to demonstrate new plants integrated into sustainable complexes. The chemical production complex of existing plants in the lower Mississippi River corridor has been taken as a base case of existing plants for study. This complex has thirteen production units containing more than one plant and associated utilities for power, steam and cooling water generation and facilities for waste treatment.

Fermentation of starch (corn) sugar (sugarcane) or lignocellulosic biomass like corn stover or switch grass in presence of suitable enzymes produces ethanol. The processes for conversion depend on the feedstock used. Ethanol is readily converted to ethylene in a process that uses an activated alumina catalyst in a fluidized bed at 300oC with a 99% conversion. Ethylene is the starting chemical for a wide range of industrial commodity chemicals like polyethylene, ethylene oxide and acetaldehyde. An integration of a plant for ethanol based on biomass feedstock will be a starting point for the production of the above commodity chemicals.

Transesterification is the addition of an alcohol such as methanol or ethanol to break the triglycerides in vegetable oil to fatty acid esters and a glycerol molecule. The fatty acid esters can be modified and polymerized using epoxydation or hydroformylation. Markets that can make use of lipid and vegetable oil based feedstock includes lubricants and hydraulic fluids, solvents, polymers and resins, plasticizers, printing inks, adhesives and surfactants, cosmetics, pharmaceuticals etc.. Transesterification using soybean oil produces 10% by weight of glycerol. Glycerol can be introduced into the propylene chain to produce chemicals. These chemicals are currently produced from natural gas. For example, Glycerol can be converted in a low pressure and temperature (200 psi and 200oC) catalytic process by hydrogenolysis to produce propylene glycol.

Thus, biomass feedstock based glycerin from transesterification process and ethanol from fermentation process can potentially be used to produce chemicals that are currently produced from fossil feedstock. The industrial scale design of these processes is integrated in the chemical production complex in the lower Mississippi river corridor.