Adsorption Equilibrium Modeling of Space Station Wastewaters

Abstract

An adsorption equilibrium model was developed for predicting the total organic carbon (TOC) removal by the International Space Station water processor's multifiltration beds. Ideal adsorbed solution theory is used to describe the competitive interactions between fictive components (FCs) that make up the TOC. The FC physical properties were based on several identified compounds to represent the distribution adsorbing compounds in the wastewaters. The TOC isotherms were performed using the wastewaters on three absorbents (a coconut-based granular activated carbon, a coal-based granular activated carbon, and a polymeric-based resin), which are contained in the multifiltration beds. The isotherms were used to validate the model for all three adsorbents. The FCs were determined in such a way that they can describe the TOC concentration for multiple beds in series.