Biopolymer-Based Mixed Matrix Membranes (MMMs) for CO2/CH4 Separation: Experimental and Modeling Evaluation

Abstract

Alternative materials are needed to tackle the sustainability of membrane fabrication in light of the circular economy, so that membrane technology keeps playing a role as sustainable technology in CO2 separation processes. In this work, chitosan (CS)-based mixed matrix thin layers have been coated onto commercial polyethersulfone (PES) supports. The CS matrix was loaded by non-toxic 1-Ethyl-3-methylimidazolium acetate ionic liquid (IL) and/or laminar nanoporous AM-4 and UZAR-S3 silicates prepared without costly organic surfactants to improve CO2 permselectivity and mechanical robustness. The CO2/CH4 separation behavior of these membranes was evaluated experimentally at different feed gas composition (CO2/CH4 feed mixture from 20:80 to 70:30%), covering different separation applications associated with this separation. A cross-flow membrane cell model built using Aspen Custom Modeler was used to validate the process performance and relate the membrane properties with the target objectives of CO2 and CH4 recovery and purity in the permeate and retentate streams, respectively. The purely organic IL-CS and mixed matrix AM-4:IL-CS composite membranes showed the most promising results in terms of CO2 and CH4 purity and recovery. This is correlated with their higher hydrophilicity and CO2 adsorption and lower swelling degree, i.e., mechanical robustness, than UZAR-S3 loaded composite membranes. The purity and recovery of the 10 wt.% AM-4:IL-CS/PES composite membrane were close or even surpassed those of the hydrophobic commercial membrane used as reference. This work provides scope for membranes fabricated from renewable or biodegradable polymers and non-toxic fillers that show at least comparable CO2/CH4 separation as existing membranes, as well as the simultaneous feedback on membrane development by the simultaneous correlation of the process requirements with the membrane properties to achieve those process targets.

Investigation of the effect of functionalized carbon nanotube and graphene oxide in guar gum‐based mixed matrix membrane for gas separation application

“…[ 44 ] The peaks at 900–1200 cm −1 are attributed to the COH stretching due to the galactose unit in the GG polymer. [ 12,45 ] In the case of GG/GO, the peak associated with stretching vibration OH at 3287 cm −1 in GG shifts to 3307 cm −1 in GG/GO, indicating the formation of GO and GG hydrogen bonding. Moreover, the intensity of the peak that arises at 1737 cm −1 in the GG polymer matrix increases when GO is incorporated into the polymer matrix, indicating an increase in the amount of oxygen‐containing group in the MMMs, which confirms the presence of GO in the GG matrix.…”

Analysis of the Techno-Economic Competitiveness of a Three-Stage Membrane Separation Process for Biogas Upgrading Using a Biopolymer-Based Mixed-Matrix Membrane

“…In addition to engineering toolboxes for process systems, combined approaches of materials and process design methods also offer a straightforward link among membrane performance, optimal process structure, and cost. Those studies could be extended to more complex systems, including multicomponent feed compositions, multimembrane systems, or multitarget problems, such as combined biogas upgrading and carbon capture objectives. ,− Significant progress has also been made in the development of membrane materials specifically designed for the separation of CO 2 /CH 4 mixtures from different sources, ranging from advanced polymers, such as thermally rearranged polymers and of intrinsic microporosity to metal–organic frameworks, carbon, silica, and zeolite types, and more recently, biopolymers. , Biopolymer-based membranes evaluated for biogas upgrading include micro- and nanocellulose, PVA blends in nanocomposite membranes, polylactic acid (PLA)-based membranes, , and chitosan (CS)-based membranes and the formulation as mixed-matrix membranes (MMMs). − These biopolymer-based MMMs seem to be sustainable alternatives for CO 2 /CH 4 separation, pending mature development for its further implementation.…”

“…Each membrane unit was represented as a crossflow membrane model based on a cell-in-series assumption, where the membrane unit was divided into 100 equal-sized cells, to solve the steady-state material balances and transport equations, being detailed in previous studies. , The separation performance was defined by the purity and recovery of each component at the outlet stream of each membrane unit, taking CO 2 and CH 4 as the key components in the permeate and retentate streams, respectively.…”

New Hydrophilic Matrix Tablets for the Controlled Released of Chlorzoxazone

“…At the predetermined time intervals (1 h), samples prevailed from the hydration medium, and the excess water on the surface was removed by wiping with filter paper and then weighed. The swelling degree [55] was evaluated using relation 5:…”