Biocatalytic Membranes for Carbon Capture and Utilization

Abstract

Innovative carbon capture technologies that capture CO2 from large point sources and directly from air are urgently needed to combat the climate crisis. Likewise, corresponding technologies are needed to convert this captured CO2 into valuable chemical feedstocks and products that replace current fossil-based materials to close the loop in creating viable pathways for a renewable economy. Biocatalytic membranes that combine high reaction rates and enzyme selectivity with modularity, scalability, and membrane compactness show promise for both CO2 capture and utilization. This review presents a systematic examination of technologies under development for CO2 capture and utilization that employ both enzymes and membranes. CO2 capture membranes are categorized by their mode of action as CO2 separation membranes, including mixed matrix membranes (MMM) and liquid membranes (LM), or as CO2 gas–liquid membrane contactors (GLMC). Because they selectively catalyze molecular reactions involving CO2, the two main classes of enzymes used for enhancing membrane function are carbonic anhydrase (CA) and formate dehydrogenase (FDH). Small organic molecules designed to mimic CA enzyme active sites are also being developed. CO2 conversion membranes are described according to membrane functionality, the location of enzymes relative to the membrane, which includes different immobilization strategies, and regeneration methods for cofactors. Parameters crucial for the performance of these hybrid systems are discussed with tabulated examples. Progress and challenges are discussed, and perspectives on future research directions are provided.

Direct Biocatalytic Processes for CO2 Capture as a Green Tool to Produce Value-Added Chemicals

“…Excellent reviews on CA and FDH immobilization have recently been published [ 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 ]. Here, some illustrative cases regarding the relevance of immobilization in enzyme stabilization are highlighted according to the immobilization method ( Figure 7 ).…”

Developing Enzyme Immobilization with Fibrous Membranes: Longevity and Characterization Considerations

“…Their large, exposed surface area is expected to contribute to high enzyme loading and efficient mass transfer. Fibrous membranes by themselves are already used for many applications, including water purification, air filtration, wound dressings, and therapeutic implants; therefore, the additional biocatalytic functionality introduced by enzyme immobilization offers many opportunities to expand the utilization of these fibrous materials [ 155 , 168 ].…”

Enhancement of Biocatalytic Activity in Enzymatic Membrane Reactors: Controlled Modification with Novel Pah/Pda Composites as a Tool to Optimize Reactor Performance

“…Biocatalytic activity of EM is a function of both conversion and flux through the membrane (equations ( 2),( 4), (6)). In all conversion tests described previously, the constant TMP of 2 bar was applied, indicating that even higher values of biocatalytic activity can theoretically be obtained once we are able to apply higher TMP (permeate flux) in the system without the (proportional) loss of conversion.…”

“…EM (also known as biocatalytic membrane) is a type of catalytic membranes employing immobilized enzymes as a source of catalytic activity, where they can be attached to the skin layer of asymmetric membrane (normal mode) or entrapped within the membrane support (reverse mode) via covalent and/or non-covalent interactions [3,4]. The recent developments in the field highlight large potential of EMs for applications in the biotechnological, chemical, food, and pharmaceutical fields, with a particular focus on degradation of environmental micropollutants, carbon capture and utilization, and use in biosensors [5][6][7][8].…”