Singlet Delta Oxygen Airflow Sterilization for Building Protection

Direct Energy Solutions will develop a prototype airflow decontamination device design for building protection from chemical and biological attacks. The decontamination device generates singlet delta oxygen (SDO) on a photocatalyst bed for the destruction of contaminants entrained in an airflow. This heating, ventilation, and air conditioning system-compatible, minimum pressure drop, chemical-biological decontamination system will: (1) use a proven, nonhazardous decontaminant; (2) quickly and permanently destroy the chemical or biological agent; (3) potentially have universal utility so that the specific chemical or biological agent does not need to be known; (4) produce no toxic residuals such as ozone; and (5) operate in both standby (routine purification) and high-power (attack protection) modes. The approach consists of using a photochemical generator of metastable SDO as a catalyst bed for the oxidation of agents in air circulation systems. SDO is a powerful yet selective oxidant that shows excellent potential to be an effective chemical-biological decontamination agent. The device consists primarily of an oxygen source (air or pure O2), a commercially available lamp as the energy source for SDO production, and a bed of granular media coated with a high-efficiency Type II photosensitizer material. The device is integrated into ductwork to treat fresh or recirculated air as it passes through the catalyst bed. The device has many potential commercial applications, including fixed or portable air purification and air sterilization for hospitals to prevent secondary infections. In Phase I, a flow tube testbed will be modified to entrain and collect controlled concentrations of chemical weapons agent (CWA) simulants in an airflow. The effectiveness of a fixed-bed SDO generator will be tested against three major classes of simulants, yielding precise fundamental reaction kinetics data that will facilitate prototype device design and performance prediction. A prototype device design will be produced. In Phase II, the prototype device design will be developed into a working prototype decontamination device that will be tested against chemical and biological simulants and live agents for performance verification. Quantitative effectiveness data for SDO against biological species will be obtained. The optimized prototype design produced in Phase II will be ready for commercial development in Phase III.