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Among several known zeolites, silicoaluminophosphate (SAPO)‐34 zeolite exhibits a distinct chemical structure, unique pore size distribution, and chemical, thermal, and ion exchange capabilities, which have recently attracted considerable research attention. Global carbon dioxide (CO2) emissions are a serious environmental issue. Current atmospheric CO2 level exceeds 414 parts per million (ppm), which greatly influences humans, fauna, flora, and the ecosystem as a whole. Zeolites play a vital role in CO2 removal, recycling, and utilization. This review summarizes the properties of the SAPO‐34 zeolite and its role in CO2 capture and separation from air and natural gas. In addition, due to their high thermal stability and catalytic nature, CO2 conversions into valuable products over single metal, bi‐metallic, and tri‐metallic catalysts and their oxides supported on SAPO‐34 were also summarized. Considering these accomplishments, substantial problems related to SAPO‐34 are discussed, and future recommendations are offered in detail to predict how SAPO‐34 could be employed for greenhouse gas mitigation. [ABSTRACT FROM AUTHOR]

Mixed‐matrix membranes (MMMs) with combination of two distinct dimensional nanofillers (such as 1D‐3D, 2D‐3D, or 3D‐3D, etc.) have drawn special attention for gas separation applications due to their concerted effects on gas permeation and mechanical properties. An amine‐functionalized 1D multiwalled carbon nanotube (NH2‐MWCNT) with exceptional mechanical strength and rapid gas transport was crosslinked with an amine‐functionalized 3D metal‐organic framework (UiO‐66‐NH2) with high CO2 affinity in a Schiff base reaction. The resultant crosslinked mixed‐dimensional nanostructure was used as a nanofiller in a polysulfone (PSf) polymer matrix to explore the underlying synergy between 1D and 3D nanostructures on the gas separation performance of MMMs. Cross‐sectional scanning electron microscopy and mapping revealed the homogenous dispersion of UiO‐66@MWCNT in the polymer matrix. The MMM containing 5.0 wt. % UiO‐66@MWCNT demonstrated a superior permeability 8.3 Barrer as compared to the 4.2 Barrer of pure PSf membrane for CO2. Moreover, the selectivity (CO2/CH4) of this MMM was enhanced to 39.5 from the 28.0 observed for pure PSf under similar conditions of pressure and temperature. [ABSTRACT FROM AUTHOR]

Mixed-matrix membranes (MMMs) with combination of two distinct dimensional nanofillers (such as 1D-3D, 2D-3D, or 3D-3D, etc.) have drawn special attention for gas separation applications due to their concerted effects on gas permeation and mechanical properties. An amine-functionalized 1D multiwalled carbon nanotube (NH 2 -MWCNT) with exceptional mechanical strength and rapid gas transport was crosslinked with an amine-functionalized 3D metal-organic framework (UiO-66-NH 2 ) with high CO 2 affinity in a Schiff base reaction. The resultant crosslinked mixed-dimensional nanostructure was used as a nanofiller in a polysulfone (PSf) polymer matrix to explore the underlying synergy between 1D and 3D nanostructures on the gas separation performance of MMMs. Cross-sectional scanning electron microscopy and mapping revealed the homogenous dispersion of UiO-66@MWCNT in the polymer matrix. The MMM containing 5.0 wt. % UiO-66@MWCNT demonstrated a superior permeability 8.3 Barrer as compared to the 4.2 Barrer of pure PSf membrane for CO 2 . Moreover, the selectivity (CO 2 /CH 4 ) of this MMM was enhanced to 39.5 from the 28.0 observed for pure PSf under similar conditions of pressure and temperature., (© 2021 Wiley-VCH GmbH.)