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The primary goals of human civilization are sustainable growth and restoration of the ecosystem. Currently, the continuous release of effluents containing heavy metals from tanneries, and the mining, printing, and pharmaceutical industries into the aquatic environment has become a serious issue. Chromium (Cr) and mercury (Hg) pose a major threat to human beings. Several techniques have been employed to mitigate this threat, including adsorption, electrolysis, chemical precipitation, desalination, reverse osmosis, ion exchange, membrane filtration, and photocatalysis. However, photocatalysis is known for its cost-effectiveness and green aspects in the removal of heavy metal ions from solutions. Over the last few decades, there has been a growing interest among researchers worldwide to study this technique. Numerous materials, including conducting polymers (CPs), have been utilized for the removal of heavy metal ions from wastewater/aqueous solutions. Polyaniline (PANI)-based nanocomposites are effective photocatalysts for the removal of various types of heavy metal ions from wastewater/aqueous solutions. Despite its potential, several factors affect the removal efficiency, such as irradiation levels and the type of PANIbased nanocomposite used. Further research is needed to address these challenges and improve the stability and reusability of PANI-based photocatalysts. Given the available water resources in the real world, it is critical that in-depth research be conducted into PANI-based photocatalysts, and the stability and reusability of such catalysts and achieving the primary goals of human civilization, namely sustainable growth and ecosystem restoration. [ABSTRACT FROM AUTHOR]

Epoxy resin is commonly used in the oil and gas industry due to its excellent toughness, low shrinkage, good adhesive strength, and relatively good thermal resistance. It is used for water shutoff, zonal isolation, cementing, enhanced oil recovery, and preventing leakage in wells. This paper reviews the chemistry aspect of using an epoxy resin system as a sealant to prevent well leakage and it offers insights into the chemistry of the epoxy resin system, as applied in previous studies. The paper also unveils the reasons for the application of this system from the chemistry perspective, allowing this aspect to be better understood. Success in the investigated cases depended on the formulation design. The epoxide and hydroxyl functional groups have been found to contribute substantially to the excellent performance of the sealant system. Furthermore, the amine curing agent triggers the abrupt reaction of the oxirane ring to stabilise when the cured sealant is perfectly applied. Based on the findings, it is suggested that other types of epoxies, namely epoxidised oils, require further study. Finally, in terms of safety and sustainable energy, it is suggested that more curing agent and diluent studies are undertaken. [ABSTRACT FROM AUTHOR]

This study investigates the effect of natural rubber (NR), epoxidised natural rubber (ENR), and core-shell rubber (CSR) as toughening agents for poly(lactic acid) (PLA). PLA/rubber blends were prepared by using melt blending method in a twin-screw extruder, with the content of rubbers was fixed at 5 wt. %. All PLA/rubber blends exhibited lower storage modulus compared to neat PLA. Two-stage storage modulus (E’) was also observed, where the first stage occurred at lower temperature corresponded to the glass transition temperature (Tg) of rubber components, whereas the second E’ corresponded to the Tg of PLA. The impact fracture surface of PLA/rubber blends also exhibited phase-separated morphology where the spherical-shaped rubber particles were clearly present in the PLA matrix.

As the world strives for sustainable development, renewable energy emerged as one of the crucial energy resources for daily consumption. Hydrogen is well known as a new renewable source that is clean and regarded to be low cost. Hence, the method to produce hydrogen in the cleanest way is in pursuit. Thermodynamic modelling using Gibbs free energy minimization is widely used in predicting various products including hydrogen. In this study, steam reforming reaction of methane combined with glycerol, a co-product from biodiesel production was performed to determine the hydrogen production trend as well as other possible products (CO, CO2, C, CH4, C2H4 and C2H6. The equilibrium composition was determined at reaction temperatures 573 K-1,273 K, pressure 1-5 bars and molar ratios glycerol-methane-steam (GMS) 1:1:1 - 12:1:1, 1:3:1-1:12:1, 1:1:3 - 1:1:12. The optimum process parameters for H2 production was attained at 1,023 K with 1 bar pressure and the molar ratios for GMS at 1:1:1. It was discovered that greater GMS ratio instantly reduced the formation of hydrogen. The knowledge from the thermodynamic analysis of glycerol-methane steam reforming is a great method to aim for highest hydrogen yield and at the same time lowering the tendency of coking process that could poison the catalyst. [ABSTRACT FROM AUTHOR]