This project will seek to develop a scalable, low cost process for the production of the energetic plasticizer, butanetriol trinitrate (BTTN), from biosynthetic 1,2,4-butanetriol (BT). BT will be synthesized from a biomass derived sugar (xylose) with metabolically engineered E. coli. This approach will eliminate the need for stoichiometric NaBH₄ (sodium borohydride), organic solvents, toxic catalysts, and extreme conditions. In addition, it will allow for the sustainable, on-demand production of BT and BTTN for use in existing and emerging propellant formulations. Successful development of this technology is expected to reduce the cost of BTTN by a factor of 7 - 10, and may allow for its expanded use in place of nitroglycerin, enhancing warfighter safety.

1,2,4-butanetriol (BT) will be synthesized from xylose with metabolically engineered E. coli. BT will be isolated from the fermentation broth by techniques including distillation, chemical trapping/extraction, and pervaporation. Pure BT will then be nitrated to form BTTN at small scale and the product will be fully characterized by common analytical techniques. This process will then be scaled up to several grams to conduct safety testing. The biosynthetic production of BT will then be further scaled up to the multikilogram scale and converted to BTTN. This material will be incorporated into a propellant formulation relevant for a joint air-to-ground missile. The cure kinetics, burn rate and basic mechanical properties of the propellant will be evaluated.

Successful execution of this project will result in a sustainable, low-cost process for the conversion of biomass sugars to BTTN. This advance will allow for the on-demand production of BTTN for both Research, Development, Test and Evaluation projects, as well as existing weapon systems. Decreasing the cost of BTTN will allow for its expanded use in propellants, improving formulator and warfighter safety.