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Hawks, Steven

Publications and source records attributed to Hawks, Steven.

System and method for using ultramicroporous carbon for the selective removal of nitrate with capacitive deionization

The present disclosure relates to a flow through electrode, capacitive deionization (FTE-CDI) system which is able to adsorb nitrates from water being treated using the system. The system makes use of a pair of electrodes arranged generally parallel to one another, with a water permeable dielectric sandwiched between the electrodes. The electrodes receive a direct current voltage from an electrical circuit. At least one of the electrodes is formed from a carbon material having a hierarchical pore size distribution which includes a first plurality of pores having a width of no more than about 1 nm, and a second plurality of micro-sized pores. The micron-sized pores enable a flow of water to be pushed through the electrodes while the first plurality of pores form adsorption sites for nitrate molecules carried in the water flowing through the electrodes.

Campbell, Patrick↗

System and method for high efficiency electrochemical desalination

The present disclosure relates to a capacitive deionization (CDI) system for desalinating salt water. The system may have a capacitor formed by spaced apart first and second electrodes, which enable a fluid flow containing salt water to pass either between them or through them. An input electrical power source is configured to generate an electrical forcing signal between the two electrodes. The electrical forcing signal represents a periodic signal including at least one of voltage or current, and which can be represented as a Fourier series. One component of the Fourier series is a constant, and a second component of the Fourier series is a sinusoidal wave of non-zero frequency which has the highest amplitude of the additive components of the Fourier series. The amplitude of the sinusoidal wave component is between 0.85 and 1.25 times the amplitude of the periodic signal.

Hawks, Steven↗