Omnya Abdalla

Belite–ye’elimite–ferrite (BYF) cement has garnered significant interest as an alternative to ordinary Portland cement (OPC) due to its lower limestone content, early-age strength development and improved durability. However, the main challenge to the commercial production of BYF cement is the requirement for large quantities of costly aluminous raw materials. The introduction of alpha prime belite (α′ C₂S) to BYF clinker would minimize production costs while maintaining mechanical properties. Herein, α′ C₂S containing BYF clinkers were synthesized and analysed to determine their properties and hydration characteristics. The clinker samples were synthesized using a previously reported clinkering technique wherein a sulfur-containing atmosphere was used, with a raw mix design including additions of a combination of boron, potassium and sodium-containing doping agents. Preliminary data showed adequate amounts of α′ C₂S were preserved, reaching more than 40 wt% of total clinker composition. Moreover, the heat release curves revealed enhanced hydration kinetics for the modified clinkers compared to the unmodified ones. While there was a noticeable improvement in ettringite precipitation upon hydration, the precipitation of strätlingite remained the same after doping. The experimental findings showed high potential for the existence of low-ye’elimite BYF clinker formulations as part of the wider portfolio of OPC clinker alternatives.

Ultrafiltration (UF) polymeric membranes are widely used in water treatment and support desalination and gas separation membranes. In this article, we enhance the performance of Polysulfone (PSF) mixed matrix membranes (MMMs) by dispersing different concentrations of thermally reduced graphene (TRG) nanofillers. The UF PSF-TRG MMMs were fabricated via the phase inversion process, and the impact of TRG loading on the characteristics of the membrane, including hydrophilicity, porosity, roughness, and morphology, were analyzed using a contact angle measurement, atomic force microscopy (AFM), scanning electron microscopy (SEM), and dynamic mechanical analysis. Incorporating TRG into the PSF matrix led to favorable effects in the instantaneous de-mixing during phase inversion, increasing the porosity and hydrophilicity of MMMs and improving the mechanical properties of the membranes. Moreover, membrane performance was examined to remove dispersed oil from oil–water emulsion and support air-dehumidification membranes. MMM performance in terms of flux and oil rejection was superior to the control PSF membrane. Incorporating 0.25% TRG into PSF resulted in a 70% water flux increase and higher oil rejection compared to the control PSF membrane. As a support for air-dehumidification membranes, the MMM also demonstrated enhanced humidity reduction and an over 20% increase in water vapor permeance over the control PSF membrane. These results indicate that the PSF-TRG MMMs are an excellent candidate for reliable oil–water separation and as a support for air-dehumidification membranes.

Porous low-pressure membranes have been used as active membranes in water treatment and as support for thin-film composite membranes used in water desalination and gas separation applications. In this article, microfiltration polysulfone (PSf)mixed-matrix membranes (MMM) containing amine-functionalized graphene oxide (GO-NH₂) were fabricated via a phase inversion process and characterized using XPS, SEM, AFM, DMA, XRD, and contact angle measurements. The effect of GO-NH₂ concentration on membrane morphology, hydrophilicity, mechanical properties, and oil–water separation performance was analyzed. Significant enhancements in membrane hydrophilicity, porosity, mechanical properties, permeability, and selectivity were achieved at very low GO-NH₂ concentrations (0.05–0.2 wt.%). In particular, the water permeability of the membrane containing 0.2 wt.% GO-NH₂ was 92% higher than the pure PSf membrane, and the oil rejection reached 95.6% compared to 91.7% for the pure PSf membrane. The membrane stiffness was also increased by 98% compared to the pure PSf membrane. Importantly, the antifouling characteristics of the PSf-GO-NH₂ MMMs were significantly improved. When filtering 100 ppm bovine serum albumin (BSA) solution, the PSf-GO-NH₂ MMMs demonstrated a slower flux decline and an impressive flux recovery after washing. Notably, the control membrane showed a flux recovery of only 69%, while the membrane with 0.2 wt.% GO-NH₂ demonstrated an exceptional flux recovery of 88%. Furthermore, the membranes exhibited enhanced humidity removal performance, with a permeance increase from 13,710 to 16,408. These results indicate that the PSf-GO-NH₂ MMM is an excellent candidate for reliable oil–water separation and humidity control applications, with notable improvements in antifouling performance.