摘要 |
A waste solution containing electroactive species, e.g., metal ions, can be remediated to very low levels of contaminant by an electrolysis method including the steps of introducing an electrolyte containing an electroactive species into an electrolytic cell having a cathode and an anode, producing a flow of the electrolyte past at least one of the electrodes at an electrolyte flow rate, and passing an electric current through the solution between the anode and the cathode whereby the electroactive species undergoes an electrochemical reaction at one of the electrodes at an electrochemical reaction rate, using an electric current pulsed at a frequency of 0.5 to 1000 Hertz and a duty cycle of not greater than 50%, and adjusting the electrolyte flow rate for the pulsed current electrolysis such that the electrochemical reaction rate for pulsed current electrolysis is greater than the electrochemical reaction rate for direct current electrolysis. The method is especially useful in increasing the efficiency of electrolytic remediation of metal-containing waste solutions to low levels of metal ion contaminants. The method is preferably conducted using electrodes having very high surface area, optionally coated with an ion exchange resin.
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