CROSS-FLOW FILTRATION OF COLLOIDS FROM AQUATIC ENVIRONMENTS

In recognition of problems associated with traditional ultrafiltration techniques, cross-flow ultrafiltration has been adapted to isolate colloidal material from natural aquatic environments, both freshwater and marine. The procedure is capable of delivering filtration rates on the order of tens of liters per hour without introducing significant quantities of organic or trace-metal contaminants, and thus is suitable for large-volume and trace-component applications. Mass balance experiments in which concentrations were measured in ultrafiltrate and retained fractions show that both organic material and several trace metals are recovered without significant losses on the filters.