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Membrane-based technology has received much attention in the past decades due to attractive features offered. Through significant breakthroughs of this technology, the mixed matrix membrane (MMM) has demonstrated a promising carbon dioxide (CO2)/nitrogen (N2) separation performance. Among the polymer materials used, cellulose acetate butyrate (CAB) polymer was selected due to its outstanding characteristics, which subsequently could improve the CO2 sorption ability. In this study, MMM was prepared by incorporating the functionalised multi-walled carbon nanotubes (MWCNTs-F) as inorganic material into the CAB polymer matrix (MMM-4F). The CAB membrane (CAB-M) was also synthesised under similar fabrication parameters via the phase-inversion method to determine the CO2/N2 separation performance. The gas permeation results showed that the CO2/N2 separation performance increased dramatically from 6.12 ± 0.09 to 11.00 ± 1.92 when 4 wt% of MWCNTs-F was incorporated into the CAB polymer matrix. The increase in CO2 permeance within the MMM was due to the embedded MWCNTs-F within the CAB polymer matrix. In this study, the new synthesised MMM proved to possess excellent CO2/N2 separation performance. However, it could further be improved by manipulating the amount of MWCNTs-F incorporated into the CAB polymer matrix. This is suitable for the gas separation field.

The rise in emission of greenhouse gases (GHGs) mainly carbon dioxide (CO2) in recent years due to rapid development of modern civilisation, has been listed as the primary contributor to global warming. To address this global issue, membrane technology was applied and developed intensively because of its superior performance in terms of efficiency and economic advantages. In this study, the cellulose acetate butyrate (CAB) polymer was selected as the polymer matrix material since it exhibited excellent film-forming properties. In addition, the wet-phase inversion technique was adopted to synthesise the membrane based on different casting conditions. The optimum outcomes of the fabrication conditions were then characterised with the scanning electron micrograph (SEM) to determine the best CAB membrane for CO2/N2 separation. The results showed that CAB-70000 fabricated with 4 wt% of CAB polymer concentration, casting thickness of 250 µm, solvent evaporation time of 5 minutes, and 30 minutes of solvent exchange for isopropyl alcohol and n-hexane, exhibited the best gas separation performance. Further, CAB-70000 showed an average selectivity of 6.12 ± 0.09 and permeance up to 227.95 ± 0.39 GPU for CO2 and 37.28 ± 0.54 GPU for N2, respectively. In summary, this study is expected to show a detailed outline of the future direction and perspective of the novel CAB polymeric membrane that is suitable to be applied in the industry, and serves as an insight for researchers and manufacturers working in the related field of gas separation.

Laparoscopy is being used more and more often in pediatric surgery for diagnostic and therapeutic indications. We report the successful laparoscopic excision of a congenital bladder diverticulum in a 6-year-old child. The minimally invasive approach allowed for easy identification and dissection of the diverticulum and surrounding vital structures with minimal postoperative pain and a good cosmetic result.