Mazlan Norhidayah, Jusoh Norwahyu, Sow Mun Lock Serene
CO(2) Research Centre (CO(2)RES), Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak, Malaysia.
Chemosphere. 2022 Nov;307(Pt 3):136019. doi: 10.1016/j.chemosphere.2022.136019. Epub 2022 Aug 14.
Gas separation of carbon dioxide (CO) and methane (CH) from landfill gas (LFG) is very crucial to be undertaken to treat significant greenhouse gases (GHG) emitted to the atmosphere. Among the well-developed conventional technologies, membrane has drawn a huge attraction from many researchers to leverage on its application, which favors an efficient and environmentally safe process. In membrane technology, inorganic membrane type requires a complex and pricey fabrication process which is contradictory from the polymeric membrane features. The impressive gas permeability and acceptable value of selectivity possessed by polymeric membranes has contributed to its main attractiveness over the other types of membranes available. Besides, the frequent approach used which is through experimental methods requires complicated procedures and possess high difficulty to obtain a defect-free membrane sample. In this work, 6FDA-durene has been investigated by employing a molecular simulation approach to further examine its fractional free volume within the membrane matrix and transport properties. The structure creation of complete framework and the analysis of project deliverables has been adopted through a molecular dynamic simulation in Materials Studio software. FFV value obtained based on the simulated framework is 0.1743 which establishes about 3.15% deviation to the published experimental works. Upon the increment of operating temperature, most of the gasses would be in their activation condition and possess higher gas diffusivities and permeabilities. However, with increasing operating pressure simulation, the membrane framework was compressed and reached its asymptotic limit at 7 atm which acts as a maximum point when the membrane system becomes saturated. In both cases, the selectivity of CO/CH gas pairs are validated with low percentage deviation (less than 10%) towards the reported experimental works hence affirms the reliability of results and methodology conducted.
从垃圾填埋气（LFG）中分离二氧化碳（CO₂）和甲烷（CH₄）的气体分离对于处理排放到大气中的大量温室气体（GHG）至关重要。在成熟的传统技术中，膜因其应用优势吸引了众多研究人员的关注，它有利于实现高效且环境安全的过程。在膜技术中，无机膜类型需要复杂且昂贵的制造工艺，这与聚合物膜的特性相悖。聚合物膜具有令人印象深刻的气体渗透性和可接受的选择性值，这使其比其他类型的膜更具吸引力。此外，常用的通过实验方法的途径需要复杂的程序，并且很难获得无缺陷的膜样品。在这项工作中，通过分子模拟方法对6FDA - 均四甲苯进行了研究，以进一步考察其在膜基质中的自由体积分数和传输性能。通过Materials Studio软件中的分子动力学模拟，构建了完整的框架结构并分析了项目可交付成果。基于模拟框架获得的自由体积分数（FFV）值为0.1743，与已发表的实验结果相比偏差约为3.15%。随着操作温度的升高，大多数气体将处于活化状态，具有更高的气体扩散率和渗透率。然而，随着操作压力模拟的增加，膜框架被压缩，并在7个大气压时达到渐近极限，这是膜系统饱和时的最大值。在这两种情况下，CO₂/CH₄气体对的选择性与报道的实验结果相比偏差百分比很低（小于10%），从而证实了所采用结果和方法的可靠性。
