Figure 3.

(a) Optimization test of flowing water device on voltage and flow rate (100 ppb of starting concentration, 5 mL min^–1 of flow rate). (b) Flowing water treatment comparison between CF and PACCF in the same optimum condition (100 ppb of starting concentration, 5 mL min^–1 of flow rate, 10 V). (c) Remaining concentrations for long-term flowing with single ion (Cu²⁺, Cd²⁺, Pb²⁺) simulated water (∼100 ppb). The heavy metal ion concentration in the output water is below the drinking safety level (100 ppb of starting concentration, 5 mL min^–1 of flow rate, 10 V). (Note: each point of 0 mL is tested on the first 5 mL of filtrated water by ICP-MS.)