Chemical Analysis of Return-To-Ground Node 1 Charcoal Air FIlters from ISS



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49th International Conference on Environmental Systems
49th International Conference on Environmental Systems


Dimethylsilanediol (DMSD) was identified as a problematic organic compound on the International Space Station (ISS) in 2010 during an increasing Total Organic Carbon (TOC) trend in the product water from the Water Processor Assembly (WPA). The likely sources of DMSD were determined to be polydimethylsiloxane (PDMS) degradation in air and hydrolysis on the Condensing Heat Exchanger (CHX). DMSD is not a health hazard, but it can degrade the performance of Water Recovery System components including the CHX and some WPA components, and it can build up in the Oxygen Generation System recirculation loop. Activated carbon / HEPA filters were designed to remove PDMS and other organosilanes from the air to prevent DMSD from entering the WRS, as presented at ICES 2015. In a continuing effort to eliminate PDMS from the air onboard the ISS as quickly as possible, four activated carbon-only filters were installed in Node 1 that had a predicted lifespan of ~1 year. Air Quality Monitor (AQM) results showed the filter was performing well after ~2.5 years. The filters were removed and replaced with HEPA filters after a high fungal count air sample. These four filters contain the same charcoal activated carbon that will be combined with HEPA filter media in the final design. The charcoal media from two returned filters was analyzed to determine loading pattern and to support assessment of recommended installed lifetime and capacity of the final filter design. The chemical analysis results are presented here.


David Jackson, The Boeing Company, USA
Elizabeth Bowman, The Boeing Company, USA
Samuel Manuel, The Boeing Company, USA
Kevin Braman, The Boeing Company, USA
Susan Snyder, The Boeing Company, USA
Alyssa Sherman, The Boeing Company, USA
Danielle Bowman, The Boeing Company, USA
ICES404: International Space Station ECLS: Systems
The 49th International Conference on Environmental Systems as held in Boston, Massachusetts, USA on 07 July 2019 through 11 July 2019.


Dimethylsilanediol Reduction, Water Processor Assembly, Charcoal Filter, Sustainability