1,3-Propanediol DuPont process

It is important that chemical engineers master an understanding of metabolic engineering, which uses genetically modified or selected organisms to manipulate the biochemical pathways in a cell to produce a new product, to eliminate unwanted reactions, or to increase the yield of a desired product. Mathematical models have the potential to enable major advances in metabolic control. An excellent example of industrial application of metabolic engineering is the DuPont process for the conversion of com sugar into 1,3-propanediol,... 

Propanediol is produced either from the reductive hydration of acrolein (Degussa-DuPont process), or through reductive carbonylation of ethylene oxide (Shell process), or through fermentation of glucose via glycerol (DuPont-Genencor process). 

For DuPont, the commercialization of 1,3-propanediol and PTT has opened up markets for industrial products from renewable resources. Through a partnership with Genencor International, DuPont has recently developed a lower-cost fermentation route that converts biomass sugars into 1,3-propanediol. DuPont plans to transition to the biobased process for... 

In the first process the yield does not exceed 65% of the starting compound due to simultaneous formation of 1,2-propanediol, while, in the second, a yield of 80% is obtained. Adding the fact that the market price of ethylene oxide is lower than acrolein, the Shell process can be regarded as economically more favorable. This is reflected in the much higher production volume reported for the production of 1,3-PD from ethylene oxide, which amounted to 45,000 t/a in 1999 as opposed to 9000 t/a from acrolein. The relatively high production costs with the acrolein process have probably induced the Dupont Company to invest in research efforts to further develop the biological process (see below). 

The seventh and final paper, "Development of a Fermentation-Based Process for 1,3-Propanediol Highlights of a Successful Path from Corn to Textile Fiber," by Tyler Ames of DuPont, reviewed the multiyear effort by DuPont and its development partners (Genecor International and Tate Lyle) to commercialize a new biocatalytic process for the production of 1,3-propanediol (PDO), a key ingredient in DuPont s new Sorona advanced polymer platform. PDO is currently being produced at pilot scale at Tate Lyle s Decatur, IL, site, and construction of a commercial-scale facility is expected to begin soon. 

Propanediol (1,3PD) is also undergoing a transition from a small-volume specialty chemical into a commodity. The driving force is its application in poly (trimethylene terephthalate) (PTT), which is expected to partially replace polyethylene terephthalate) and polyamide because of its better performance, such as stretch recovery. The projected market volume of PTT under the trade-names CORTERRA (Shell) and Sorona 3GT (Dupont) is 1 Mt a-1 within a few years. In consequence, the production volume of 1,3PD is expected to expand from 55kta-1 in 1999 to 360 kt a-1 in the near future. 1,3PD used to be synthesized from acrolein by Degussa and from ethylene oxide by Shell (see Fig. 8.8) but a fermentative process is now joining the competition. 

In a joint venture with Tate and Lyle PLC, known as DuPont Tate Lyle BioProducts LLC, DuPont plans to produce 1,3-propanediol (PDO) using their proprietary fermentation and purification process based on corn-derived glucose. Sample quantities of the biobased PDO are currently produced at a pilot plant in Decatur, Illinois and beginning in 2006, commercial-scale quantities will be produced at a manufacturing facility in Loudon, Tennessee (10). 

A novel polyester G3T from DuPont may also be obtain by a renewable production of 1-3 propanediol via fermentation of glucose/starch. Improving the process through identifying genes for appropriate metabolic enzymes is being attempted [362]. 

In 2004, DuPont developed a greener process to produce 1,3-propanediol (PDO) through fermentation of glycerol. Following the reaction, the PDO needs to be recovered from the fermentation broth, and vacuum distillation is used. We want to determine the composition of the vapor phase in equilibrium with a liquid containing 40% PDO and glycerol at 180 °C. 

---