An electrospray-based, ozone-free air purification technology

A zero-pressure-drop, ozone-free air purification technology is reported. Contaminated air was directed into a chamber containing an array of electrospray wick sources. The electrospray sources produce an aerosol of tiny, electrically charged aqueous droplets. Charge was transferred from the droplets onto polar and polarizable species in the contaminated air stream and the charged contaminants were extracted using an electric field and deposited onto a metal surface. Purified air emerged from the other end of the chamber. The very small aqueous electrospray droplets completely evaporate so that the process is essentially dry and no liquid solvent is collected or recirculated. The air purification efficiency was measured as a function of particle size, air flow rate, and specific system design parameters. The results indicate that the electrospray-based air purification system provides high air purification efficiency over a wide range of particle size and, due to the very low power and liquid consumption rate, can be scaled up for the purification of arbitrarily large quantities of air.