Formaldehyde is one of the most common difficult-to-eliminate indoor air pollutants. Among the available methods of eliminating formaldehyde, adsorption is still the most commonly used due to its simplicity, efficiency, and economic viability. This study investigated the potential of diatomaceous earth (DE) adsorbent for formaldehyde (low concentration in air). DE was considered because of its high silica content and high porosity. It also examined the effect of adding ethylene-diamine (EDA) on the adsorption performance of DE. Amine groups have been proven to improve the adsorption of formaldehyde through their reaction that produces imine. The amount of added EDA was varied from 0.25 to 0.75 g per gram of DE. For pure DE adsorbent, the adsorption performance was 298 mg/g. Adding 0.75 g of EDA resulted in maximum DE adsorption performance (565 mg/g). EDA-modified DE was shown to be a potential adsorbent for removing formaldehyde in air.

This study explored the application of MOF-modified membrane for gas separation. Microporous aluminum fumarate (A520) was used to modify polyimide (PI) membrane using N-methylpyrrolidone (NMP) as solvent. The MOF-modified mixed matrix membrane (MMM) was subjected to gas permeability tests, using gas permeability apparatus (GPA). GPA results showed that adding 10wt% MOF to the membrane increased permeabilities of N2 and CO2 gases by up to 34%, and by 19% for O2 gas, without compromising selectivity. Further increasing MOF loading beyond 10wt% considerably decreased selectivities despite significantly increased permeabilities. Cahn adsorption experiment confirmed and supported this GPA data. These results indicate that MOF were successfully intercalated with the polymer as revealed by scanning electron microscope (SEM) images. Other characterizations like dynamic mechanical analysis (DMA), x-ray diffraction (XRD), and positron annihilation lifetime spectroscopy (PALS) showed that the interface and mechanical properties of the MMM also improved. MOF loading beyond 10wt% revealed aggregations forming non-selective voids that probably caused lowered selectivity.

Microporous aluminum fumarate (A520) is one of the very few metal-organic frameworks (MOFs) that have been promoted to the level of commercial applications and has recently been proven to exhibit a rigid character with an accessible permanent porosity. This study explored the maximum loading amount of A520 for mixed matrix membrane (MMM) preparation by blending it with polyimide (PI) using N-methylpyrrolidone (NMP) as solvent, without compromising the membrane integrity. Scanning electron microscope (SEM) images revealed that MOFs were able to infiltrate the pores and structures of the polymer, improving the interface and mechanical properties of the polymer, as supported by different characterizations like dynamic mechanical analysis (DMA), x-ray diffraction (XRD), and positron annihilation lifetime spectroscopy (PALS). Results showed that MOF loading beyond 10wt% revealed aggregations that compromised the integrity of the membrane.

Polyvinylidene fluoride (PVDF) membranes, enhanced with metal-organic framework (MOF), were fabricated on a non-woven polyethylene terephthalate (PET) support using the non-solvent induced phase inversion (NIPS) method to produce mixed matrix membrane (MMM). Polymer concentration of 10%, 15%, and 20% were used in the study whereas UiO-66(Zr) was used as a MOF filler. The resulting membranes were characterized in terms of their morphology, porosity, wettability, mechanical strength, pure water flux, and gas permeability. Results show that the presence of UiO-66(Zr) filler improved membrane morphology, mechanical strength, and hydrophobicity of MMM as compared to pristine PVDF.

Copper (II) oxide (CuO) was successfully synthesized via sonochemical-assisted route, where it was incorporated in cellulose acetate (CA) to develop an antimicrobial textile by electrospinning. The CuO material was found to have a monoclinic crystal structure as determined by x-ray diffraction analysis (XRD). On the other hand, scanning electron micrographs (SEM) have shown spindle like morphology for the synthesized CuO. The micrographs of the electronspun material were found to have a smooth and bead-free morphology with a fiber diameter that range from 1.9 to 4.3 μm. The presence of CuO oxide in the polymer matrix was determined by energy dispersive x-ray spectroscopy (EDX) and optical microscopy. The actual loadings of CuO into the polymer matrix are slightly different from the expected amount, which might be attributed to the heterogeneous dispersion of the latter to the former. The incorporation of CuO in the polymer membrane slightly affected tensile property of the composite material. The CuO-CA samples were found to have antimicrobial activity againstPseudomonas aerugenosaATCC 27853 as evaluated by Kirby-Bauer disk diffusion method. The present study has demonstrated the possibility of using the fibrous mats of cellulose acetate-copper oxide as a novel antimicrobial textile.