NOx decomposition with repetitive discharges by reciprocal voltage pulse in a coaxial cable

We propose a method for NO/sub x/ decomposition using a reciprocal pulse generator. The pulse generator consists of only a few components; a coaxial cable, a grounding switch and a DC voltage source. When the cable was charged and then grounded at one end of the cable without any resistance, a traveling voltage pulse reciprocated in the cable with a change in its polarity, so that the voltage pulse was repeatedly applied to a barrier-type reactor at the open end. In tests of NO removal, the pulse generator gave a better performance compared with a self-matched pulse generator. Results of an optical study showed that gas molecules in the reactor were repeatedly exposed to intense pulsed discharges with a very high frequency because the voltage oscillation caused by one switching induced alternate propagation of positive and negative streamers from a wire electrode in the reactor.