Green oxidizer compositions and methods

Inventors

Smith, Jr., James Edwin • Zhang, Chen • Lei, Yu

Assignees

University of Alabama in Huntsville

Abstract

The present disclosure generally pertains to green oxidizer compositions and method of synthesizing and using the same. Such green oxidizers are stable, may be used in conventional bipropellant thrusters, including, but not limited to LDACS applications, and offer several benefits over conventional oxidizers with respect to toxicity and/or corrosion. The present disclosure also relates to methods of synthesizing poly-nitrated oxetane, a green oxidizer, in an Argon-rich environment.

Core Innovation

The invention provides green oxidizer compositions, specifically poly-nitrated oxetane, and details methods of synthesizing and using these oxidizers. Unlike conventional oxidizers such as nitrogen tetroxide or inhibited red fuming nitric acids, which are toxic and corrosive, the disclosed green oxidizers are stable and offer significant benefits in terms of reduced toxicity and corrosion. A key focus of the invention is the optimized synthesis of poly-nitrated oxetane in an argon-rich environment, with careful control of mixing and temperature to maximize product yield and stability.

The method involves preparing a nitrating mixture by adding fuming nitric acid to sulfuric acid, cooling it, incrementally adding 3-hydroxyoxetane, and alternating between periods of no mixing and vigorous mixing to control the exothermic reaction. Proper heat management and quenching with ice water are necessary to prevent decomposition and maximize the stability of poly-nitrated oxetane. Post-processing steps such as vacuum evaporation or decanting after freezing are used to reduce moisture content in the final product.

The disclosed green oxidizer can be used in conventional bipropellant thrusters, including applications for Liquid Propulsion Divert and Attitude Control Systems (LDACS), and with both hydrazine and ionic liquid fuels. The bipropellant composition offers the advantage of compatibility with existing thruster technologies and can also be used as a monopropellant, generating NO2 gas when heated. This addresses the unmet need for greener, hypergolic oxidizers that do not have the safety and handling concerns of traditional options.

Claims Coverage

There is one independent claim in the patent, from which multiple dependent claims stem. The main inventive feature pertains to the method involving spraying a specific oxidizer and fuel in a thruster combustion chamber to generate propulsion.

In summary, the claims cover the inventive use of poly-nitrated oxetane as a green oxidizer in combination with a fuel for generating propulsion in thruster systems. The method highlights compatibility with several fuel types and both conventional and future greener propulsion applications.

Stated Advantages

Documented Applications