VOC emission control using novel adsorbents and their regeneration

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About 2.16 megatonnes of volatile organic compounds (VOCs) were emitted to the atmosphere in Canada in 2014. Major sources of these emissions include the oil and gas industry (34%) and processes using organic solvents (15%). VOCs are precursors to ground-level ozone and many VOCs may be carcinogenic and/or neurotoxic. Therefore, technologies need to be developed to efficiently control these emissions, at lower cost. Technologies need also to foster sustainable development through promoting recycling and reusing whenever feasible. Adsorbents are material with large surface area and porosity which help them selectively remove impurities (adsorbate) from gas streams in a process called adsorption. Desorption is the reverse of adsorption (i.e. release of adsorbate from the adsorbent). Adsorption is typically followed by regeneration to clean the adsorbent by desorbing the adsorbate. Adsorption with regeneration (or desorption) is a desirable technique for air pollution control, particularly for VOCs capture, typically emitted from solvent-based processes. Adsorption with regeneration is also used for gas separation and purification as a replacement to the more energy intensive cryogenic distillation in separation of hydrocarbons or to amine absorption. Metal Organic Framework (MOF) is a class of adsorbents with extremely high surface area, high porosity and tunable pore sizes, that can be readily used for adsorptive separation and pollution control processes.To enhance VOC emissions control, previous research focused on improving the adsorption properties of adsorbents. However, little or no research has been conducted to enhance the regeneration properties of adsorbents including reducing the energy consumption during the regeneration process. New regeneration techniques such as microwave and resistive heating regeneration have emerged as more effective techniques compared to traditional regeneration with steam or hot inert gas due to their higher energy efficiency and desorption effectiveness. Hence, there is a need for better understanding of how the electric and dielectric properties of MOF and adsorbates affect resistive and microwave heating regeneration, respectively. The objectives of this research are: 1) Understand the impact of MOF's metal cluster on its electric and dielectric properties; 2) Regenerate MOFs using resistive heating; 3) Regenerate MOFs using microwave heating; and 4) Monitor MOFs loading using a non-contact microwave sensor.This research will contribute to sustainable development in Canada by improving the air quality through more effective capture of air pollutants emissions, lower energy consumption, and lower greenhouse gas emissions. It will also contribute to the training of high quality personnel in areas of strategic importance to Canada to improve industrial activities without compromising the quality of the environment.