SBIR-STTR Award

Estes Energetics will demonstrate a two-step, electrochemical-based process for the synthesis of potassium nitrate compliant with MIL-P-156 starting with domestically available potassium chloride and nitric acid as process inputs. This process will combine widely available materials and processes from the chlor-alkali industry and acid/base chemistry while collecting data aimed towards continuous processing. This approach mitigates technology development risk, promotes efficiency and automation, and secures supply chains. We will also explore using the same capital equipment, processes, and expertise to produce other critical nitrates, such as strontium nitrate, barium nitrate, and lead(II) nitrate. The Estes Energetics team provides the qualifications and skills needed to research, build prototype reaction equipment, test the potassium nitrate, and conduct engineering and economic analyses. We have opened communication with domestic suppliers of potassium chloride and nitric acid and have identified potential vendors for electrochemical cell and reactor technologies for a follow-on Phase II. As a significant user of potassium nitrate for the manufacture of black powder through the Estes’ subsidiary Goex Industries, Estes is well versed in the purchase, handling, testing, and application of potassium nitrate.

Estes Energetics is standing up domestic production of potassium nitrate, a critical chemical used several different market segments, including the defense industry. In this Phase II effort Estes Energetics will develop a pilot-scale production line that can be modularly expanded to greater potassium nitrate production rates and to other critical nitrates. The Phase II effort will scale up the process developed in Phase I to a pilot scale production line capable of producing approximately 160,000-250,000 pounds per year. Our plan includes several risk management approaches. The two process steps we identify as having the greatest technical risk are the crystallization step and the chlorine gas processing step. To mitigate these risks, we will first focus our efforts on the design and scale-up of the latter half of the process (acid-based reaction of potassium hydroxide, followed by crystallization and drying). We will refer to this as Phase A. Potassium hydroxide can be purchased commercially in the US, so we can initially operate the pilot plant using potassium hydroxide as an input instead of potassium chloride. This intermediate process step also eliminates generating chlorine gas and thus the requirement for chlorine gas processing. The first technical objective is to demonstrate production of potassium nitrate from industrially relevant domestic sources of potassium chloride and nitric acid at a pilot scale (hundreds of thousands of pounds per year). The second technical objective is to ensure that the potassium nitrate being synthesized is compliant with MIL-DTL-156. The third technical objective is to demonstrate the operation of the pilot line at an operationally-relevant pace and economically viable manner, as determined by the throughput target set during the preliminary design task. Completion of these objectives will align well with the desired deliverables outlined in discussions with stakeholders. The focus in Phase II will be scaling up the Phase I process to an operationally relevant scale that can be modularly expanded to a throughput of several million pounds per year. The expected end result is a clear demonstration of a pilot-scale production process that can produce MIL-DTL-156 compliant potassium nitrate at an operationally-relevant scale and in an economically viable manner.