Abstract: An example method of decontaminating a fuel reactant stream for a fuel cell flows the fuel reactant stream through a fluidized ammonia dissolving media, while simultaneously flowing water through the fluidized ammonia dissolving media to separate contaminants from the fuel reactant stream into a separated contaminant and water stream. The separated contaminant and water stream from the fluidized bed is accumulated within an accumulator, circulated through a water-control loop, and decontaminated by flowing the stream through an ion exchange bed secured in fluid communication with the water-control loop. A decontaminated water stream from the ion exchange bed is circulated back through the ammonia dissolving media. A temperature of the fuel reactant stream is controlled upstream of the fuel reactant stream entering the separator scrubber to produce a predetermined temperature of the fuel reactant stream passing through the separator scrubber.