Ammonia Removal from Rodent Habitat Operations in Space Using Phosphoric Acid Treated Activated Carbon

Abstract

To accommodate long duration biology research with rodent habitats on the International Space Station while providing a healthy living and working environment for crewmembers, NASA Ames Research Center developed a new exhaust filter for odor control for the Animal Enclosure Module (AEM), which houses mice and rats. The new exhaust filter uses activated carbon pellets as adsorbents, with phosphoric acid (H 3 PO 4 ) impregnated on the surface. The deodorization performance of the new exhaust filters for AEM units housed with mice was evaluated. The ammonia breakthrough time of the exhaust filters was also investigated. The results indicated that H 3 PO 4 treated activated carbon exhibited a high ammonia adsorption capacity of more than 90%. Furthermore, the new exhaust filter can effectively control the odor from the AEM units for a 45-day (minimum) flight mission with a given animal biomass.

Air purifier devices based on adsorbents produced from valorization of different environmental hazardous materials for ammonia gas control

“…This result may be explained by the high BET surface areas of ACs 28 and/or the surface functional groups on the prepared AC samples due to the activation process. 29 The comparison of three AC samples showed that ECAC is the best adsorbent followed by RSAC and then CDAC with a range of investigated ammonia concentrations. ECAC (S BET , 1200 m 2 g À1 ) presents the highest specic surface, while CDAC has the lowest one (700 m 2 g À1 ).…”

Effects of Moisture on NH3 Capture Using Activated Carbon and Acidic Porous Polymer Modified by Impregnation with H3PO4: Sorbent Material Characterized by Synchrotron XRPD and FT-IR

“…Hence, activated carbon impregnated with H 3 PO 4 (H 3 PO 4 /C) samples were prepared in this study to remedy the drawbacks of H 2 SO 4 /C. Like H 2 SO 4 /C, the spent H 3 PO 4 /C can also be regenerated by flowing low-pressure steam through the adsorbent bed and the regeneration byproduct (NH 4 ) x H 3-x PO 4 [19] can be used as agricultural fertilizer.…”