Long term stability of capacitive de-ionization processes for water desalination: The challenge of positive electrodes corrosion

Asymmetric capacitive deionization utilizing nitric acid treated activated carbon fiber as the cathode

“…The emergence of this shoulder peak indicates that both cations and anions were expelled from the electrodes instead of being adsorbed when voltage was initially applied [59,60]. Therefore, for 0-CDI, more charge is used for co-ion expulsion as the cycling test proceeds, leading to diminished CDI performance.…”

Activated carbon electrodes: Electrochemical oxidation coupled with desalination for wastewater treatment

“…The performance deterioration may be attributed to organic fouling of the electrodes. Besides, the anode is probably oxidized at 2.0 V and O 2 -abundant condition (Cohen et al, 2013). To clarify this, a solution of 0.1 M NaOH is circulated to wash the electrodes, and then they are used for the sixth run.…”

Desalination with porous electrodes : Mechanisms of ion transport and adsorption

“…Experiments were conducted with aerated and deaerated feed water. Clearly, a decrease of desalination performance is observed over time, which is for the aerated case stronger than for the deaerated case, and is in agreement with other studies [3,64,100,120,170,171]. After 45 hours of desalination, for the aerated case, salt adsorption becomes negative, which means that salt is adsorbed during discharge (charging voltage 0 V), and desorbed during charging (discharge …”

“…Whereas MCDI has shown stable long-term performance [102], CDI shows a declining desalination performance over time, especially if dissolved oxygen is present in the feed water [3,64,100,120,170,171]. This decrease in desalination performance has been mainly attributed to faradaic reactions involving carbon oxidation [63][64][65].…”