VOC emission control using novel adsorbents and their regeneration

2014年，加拿大向大气中排放了约216万吨挥发性有机化合物（VOCs）。这些排放的主要来源包括石油和天然气工业（34%）和使用有机溶剂的过程（15%）。挥发性有机化合物是地面臭氧的前体，许多挥发性有机化合物可能具有致癌和/或神经毒性。因此，需要开发技术，以更低的成本有效地控制这些排放。技术还需要在可行的情况下通过促进回收和再利用来促进可持续发展。******吸附剂是具有大表面积和孔隙度的材料，可以帮助它们在吸附过程中选择性地从气流中去除杂质（吸附物）。解吸是与吸附相反的过程（即从吸附剂中释放吸附物）。吸附后通常是再生，通过解吸吸附物来清洁吸附剂。再生吸附（或解吸）是一种理想的空气污染控制技术，特别是对挥发性有机化合物的捕获，通常是由溶剂型工艺排放的。再生吸附也用于气体分离和净化，作为碳氢化合物分离或胺吸收中更耗能的深冷蒸馏的替代品。金属有机骨架（MOF）是一类具有极高表面积、高孔隙率和孔径可调的吸附剂，可方便地用于吸附分离和污染控制过程。******为了加强VOC的排放控制，以往的研究主要集中在提高吸附剂的吸附性能上。然而，如何提高吸附剂的再生性能，包括降低再生过程中的能耗，目前还没有相关的研究。与传统的蒸汽或热惰性气体再生相比，微波和电阻加热再生等新的再生技术由于其更高的能源效率和解吸效率而成为更有效的技术。因此，有必要更好地了解MOF和吸附剂的电学和介电性质分别如何影响电阻和微波加热再生。******本研究的目标是：1)了解MOF的金属团簇对其电性能和介电性能的影响；2)电阻加热再生mof；3)微波加热再生mof；4)使用非接触式微波传感器监测MOFs负载。******这项研究将通过更有效地捕获空气污染物排放、降低能源消耗和减少温室气体排放来改善空气质量，从而促进加拿大的可持续发展。它还将有助于在对加拿大具有战略重要性的领域培训高质量的人员，以便在不损害环境质量的情况下改善工业活动。

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.