Capacitive Properties Of Carbon Nanotubes Film And Its Application In Water Purification

Our Society and economy have been in a rapid mode of development. However, the shortage of purified water resources has been more and more aggravated by large quantities of daily consumption and varieties of contamination. Not only governments but also people have kept more and more concentration on the purification and reuse of polluted water, seawater, and salty water. Among different kinds of deionization technologies such as evaporation, reverse osmosis, and electrodialysis, capacitive deionization (CDI) has been shown to be a more efficient, minimally polluting, cost-effective, and energy-saving water purification technology since it is conducted at low voltages with no secondary waste and requires no high-pressure pumps, distillation columns, high direct current voltage, thermal heaters or chemicals.In this dissertation, graphite was chosen as the substrate. A thin layer of nickel was deposited on its surface. Then the low pressure and low temperature chemical vapor deposition (CVD) system was used to synthesize carbon nanotubes (CNTs) film on the graphite. The capacitive properties and electrosorption process of as-grown CNTs film electrodes were investigated as the following:1) The electrosorption behavior of CNTs film electrodes at different voltages and initial concentrations of electrolytes;2) The preferential electrosorption of CNTs film electrodes;3) The regeneration properties of CNTs film electrodes.Ion-exchange membranes were employed in the CDI system to fabricate a membrane capacitive deionization system (MCDI). Compared with CDI, MCDI showed much higher removal ratio.