Electrocoagulation shows strong potential for removing a wide range of contaminants from drinking water. However, the technology's simplicity and versatility belie the complex mechanisms that drive contaminant removal and transformation. Not only may source water's organic content, pH and dissolved solids affect contaminant removal, but the reactor parameters optimal for one contaminant may not be effective against another. Furthermore, organics, metals and pathogens may compete, inhibit or otherwise influence removal in a mixed-contaminant influent. This study investigates the removal of heavy metals, hardness and viruses from potable water via electrocoagulation. Heavy metals and hardness are studied at concentrations relevant to potable water and analyzed by inductively coupled plasma mass spectrometry as well as relevant methods for titration and spectroscopy. Virus removal is tested via bacteriophage surrogates MS2, phiX174 and fr. Bacteriophage plaque-forming unit (PFU) concentrations are determined via double-agar method. Removal efficiencies for all contaminants are determined first in minimal electrolyte solutions, then in complex water matrices typical of ground and surface waters in North America and India. Water matrices are varied to test the effects of pH, total dissolved solids (TDS), natural organic material (NOM) and turbidity on contaminant removal. Influents containing heavy metals, hardness, NOM and viruses are tested to determine potential competition and interactions between contaminants. Electrocoagulation is conducted using a bench-scale reactor capable of batch or continuous flow operation. Reactor parameters of current density and residence time are varied. Aluminum and iron electrodes are compared for all contaminants studied. A mass balance approach is used to determine the fate of contaminants in the flotation layer, solution and sediment. To determine electrocoagulation's potential as a pretreatment process for filtration, post-electrocoagulation samples are filtered through glass-fiber and 0.45 �m cellulose nitrate filters. Both filtrates are tested for enhanced contaminant removal.

Removal of heavy metals, hardness, and viruses from drinking water using electrocoagulation

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.