Nanoadsorbent and Microwave Technology to Capture and Recover Organic Vapors

Emissions of volatile organic compounds (VOCs) and hazardous air polutants (HAPS are a serioud environmental issue. These pollutants are requlated to protect human health and encourage the development of better control technologies. Current technologies to control thses emissions, until better materials are developed, include destructive and/or recovery-based technologies. Implementation of adsorption-based technologies will allow for the recovery and reuse of the materials removed from the gas stream, consumption of less resouces, generation of less waste, and a more sustainable integration with our environment. Granular activated carbon (GAC) is typically used as the adsorbent to control VOC/HAP emissions. GAC is usually regenerated with vacuum, hot air or steam. This project will use activated carbon fiber cloth (ACFC) as the absorbent because of its unique adsorption and regenerationproperties. This pure polymeric nanoscale material has pore widths of 0.7 nm and fiber diameter of 12 um, in contract to GACs that contain impurities and have pore widths and diameter that are orders of magnitude larger. ACFC's nanopores provide selective "condensers" for the vapors in a pure carbon matrix. Microwaves will regenerate the ACFC to eliminate the use of steam and reduce energy consumption. Microwave swing adsorption (MSA) is innovative because it combines a simple yet highly effective annular fixed-bed of ACFC adsorbent with energy efficient microwave energy. This simple yet robust system will effectively capture and recover VOCs/HAPs from air streams without ancillary heat exchangers or absorbers, with no moving parts, at ambient pressure, and is readily scalable. A laboratory-scale MSA system will be used to simulate the capture and recovery of 1) organic vapors emitted from petroleum bulk terminals and 2) perchloroethylene from dry-cleaning facilities. Capture and recovery efficiencies > 99% VOC/HAP will be achieved and > 2,800 Tons/yr of VOCs/HAPs will be removed. The new technology will be evaluated and com0pared to editing technologies based on energy and material balances and economic analysis. The intellectual merit of this research is demonstrated by the project's ability to more effectively capture and recover VOCs/HAPs from gas streams. Ambient air quality will be improved and the VOCs/HAPs will be recovered for reuse until suitabe material substitutes are developed. This project will develop a new technology that decreases the impact of industrial emissions on human healthat lower cost for a wide range of vapors and improves our ability to recycle until approptiate substitutes are available.