Recycling waste asphalt is increasingly important amid growing highway maintenance demands and environmental concerns, yet volatile organic compound (VOC) emissions during recovery remain poorly understood. This study investigates how waste soybean oil (WSO) affects VOC emissions and regeneration properties of aged 70# asphalt. WSO was blended at 4%, 6%, 8%, and 10% concentrations and characterized by way of gas chromatography–mass spectrometry, Fourier transform infrared (FTIR), and gel permeation chromatography. Rheological performance was evaluated using a dynamic shear rheometer (high-temperature) and bending beam rheometer (low-temperature), with microstructure observed by atomic force microscopy (AFM). Results show WSO significantly reduces VOC emissions – 8% WSO achieves a 33.23% reduction against unmodified asphalt, with notable decreases in toxic aromatics and sulfur-containing compounds. Molecular analysis revealed WSO replenishes light and aromatic components, restoring colloidal stability to 92% of unaged asphalt while inhibiting oxygen- and sulfur-containing compound formation. Performance tests showed that 8% WSO provides high-temperature rutting resistance comparable to new asphalt and reduces low-temperature creep stiffness to 46.9% of aged asphalt, improving crack resistance. AFM confirmed that WSO alleviates asphalt aggregation and optimizes colloid structure. Therefore, 8% WSO is the optimal dosage, achieving the best balance between VOC inhibition and regeneration performance.
In the present investigation, optimization of the viscoelastic and mechanical properties of a functionalized multi-walled carbon nanotube (MWCNT) and carbon fiber-reinforced epoxy nanocomposite was carried out. The process parameters used in this investigation are MWCNT content (wt.%), sonication time (min), and ball milling duration (min). Taguchi orthogonal array (L9) was employed to design the experimental runs and study the effect of each parameter on the responses. Response variables used in this investigation are storage modulus, loss modulus, glass transition temperature (Tg), and tensile strength. A regression model in terms of process variables was developed and validated through confirmation experiments performed at the optimum conditions of 2 wt.% MWCNTs, 60 min of sonication, and 180 min of ball milling. The predicted and experimental values of storage modulus (41.815 against 38.2 ± 4.05 GPa), loss modulus (3.94 against 3.89 ± 0.15 GPa), Tg (138.81 against 135 ± 9.94°C), and tensile strength (941.45 against 942 ± 28.59 MPa) were found to be in close agreement, confirming the reliability of the developed models. Microstructural examination of the optimized composite using microscopy revealed a uniform dispersion of MWCNT’s within the epoxy matrix, contributing to the improved interfacial bonding and load transfer.
This study presents a green and facile strategy for synthesizing a novel carbon quantum dots (CQDs)/silver (Ag)/talc ternary composite through the valorization of waste oil tea (WOT) and natural talc. The synthesis involves a three-step process: first, WOT is hydrothermally converted into CQDs; second, these CQDs act as a green reductant to form a CQDs/silver complex in situ at room temperature without any external agents; finally, the CQDs/silver complex is integrated with talc to yield the final composite. In the resulting material, talc serves as a macroscopic support providing a stable layered scaffold, WOT-derived CQDs function as a multifunctional green reductant and molecular bridge while also enhancing adsorption performance, and in situ formed silver nanoparticles (NPs) deliver the core antibacterial functionality. The composite exhibits an enhanced methylene blue adsorption capacity (20.79 mg·g−1) compared to pristine talc, consistent with the Langmuir isotherm and pseudo-second-order kinetics. Moreover, it demonstrates superior broad-spectrum antibacterial activity, achieving >99.98% inhibition against both Escherichia coli and Staphylococcus aureus. This work establishes a successful ‘waste-to-wealth’ and ‘mineral-upgrading’ paradigm based on a CQDs-mediated in situ reduction and chemical anchoring strategy, converting low-value resources into a high-value-added multifunctional material with promising potential for water-purification applications.
In the present work, we developed an efficient strategy to prepare high performance nanofiltration membrane. The polyethersulfone (PES) substructure were chosen as a support layer. Dopamine, polyethyleneimine (PEI) and MXene were used to modification the PES through co-deposition as intermediate layer. The physicochemical properties of membranes were analysed to confirm the successful modification. These modification membrane was evaluated through separation of aqueous salt solution (sodium sulphate (Na2SO4), magnesium sulphate (MgSO4), magnesium chloride (MgCl2), and sodium chloride (NaCl)). Results showed that the modified membranes exhibit enhanced hydrophilicity and reduced surface charge, which contributed to improved antifouling performance. The separation performance demonstrated that the modified membranes exhibiting higher water permeance and enhanced salt rejection. Typically, the optimum membrane achieved a water permeance of 22.25, 19.63, 21.34, and 23.36 L·m−2·h·−1·bar−1 for sodium sulphate, magnesium sulphate, magnesium chloride, and sodium chloride solution, respectively. Compared with the pristine membrane, the membrane modified by dopamine/PEI and nanofiller present significant enhanced of about 58.92%, 46.49%, 47.17%, and 53.68%, respectively. Moreover, the long-term stability tests were carried out. The membrane exhibited stable separation performance during the 75 h continuous test. This novel strategy provides a promising route to fabricate composite membranes, indicating great potential for practical wastewater treatment.
The need for highly strengthened, lightweight materials for working applications has led to a rise in the use of composites reinforced with fibers of natural or synthetic materials. Fiber-reinforced polymer composites have excellent mechanical capabilities and resistance to wear, corrosion, impact, and fire in addition to their high strength-to-weight ratio. These features have been made to use the fiber-reinforced polymer composites in various applications like automobile, marine, aerospace, construction, and many manufacturing industries, manufacturing processes, mechanical properties, thermal characteristics, and tribological behavior of composite materials determine their performance. Consequently, in order to determine the optimal material characteristic for the intended application, it is necessary to study all these things used to fabricate the composite materials. The study of This review includes the current research efforts on natural fiber-reinforced polymer composites manufacturing processes, impact modification, improved mechanical properties, thermal properties, and tribological behaviors. Improvements in the composites' mechanical, thermal, and physical properties are made possible by hybridization. This review also covers the hybridization of polymer composites and studies 3D printing a new advancement in the fabrication of polymer composites.
