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This study tackles the persistent challenge of producing highly reinforced lignin-rubber composites, emphasizing the transformation of agro-industrial residues into value-added products. To address this challenge, we introduce a novel approach termed "in-situ surface modification utilizing a thermo-chemo-mechanical approach" which incorporates the utilization of biomass-derived kraft lignin and a thermally stable organofunctional surface modifier, specifically (3-aminopropyl) triethoxysilane. The resulting material exhibits unprecedented tensile strength (∼15 MPa) along with ∼300 % elongation at break, while typical gum rubber offers 1–2 MPa tensile strength. Additionally, for the other tensile properties like 100 %, and 200 % tensile modulus, the improvement is 7-fold (∼5.6 MPa) and 10-fold (∼11.3 MPa), respectively. Furthermore, this composite presents a higher degree of reinforcement than a passenger car radial (PCR) tire model compound (tensile strength ∼14.5 MPa, 100 % tensile modulus ∼2.2 MPa, and 200 % tensile modulus ∼5.6 MPa) comprised of silica and polysulfide-based coupling agent, with exactly a similar loading of filler. The dynamic mechanical and stress relaxation behavior of the composites are critically discussed concerning the dispersion of the lignin in the sSBR/BR rubber matrix. The morphological orientation and involved chemical interaction in the presence of a surface modifier are also studied in detail. Tear fatigue analysis using pure shear specimens indicates superior fracture toughness at a lower tearing energy regime compared to silica-filled PCR tire compounds. Overall, this study showcases the potential of lignin-reinforced elastomers, offering a promising route for sustainable engineering materials and commercial viability. [Display omitted] • High mechanical performance of Lignin-rubber composites by thermo-chemo-mechanical mixing. • Better dispersion of the lignin particle in butadiene rubber at higher temperature. • Composite shows ∼15 MPa of tensile strength, like Passenger Car Radial tire compound. • Excellent fracture toughness at low tearing energy regime. • Lignin, an alternative to conventional fillers, especially for the tire applications. [ABSTRACT FROM AUTHOR]

Annually, industries related to agricultural products generate substantial volumes of waste biomass, presenting critical challenges for solid waste management due to its environmental and health implications. Pyrolysis emerges as a significant technique for converting such waste into biochar (BC), a material with notable internal microstructure, porosity, and chemical properties, contingent on the feedstock and processing conditions. BC is recognized for its exceptional water retention and alkalinity, primarily utilized for soil enhancement and fertilization. Its application across various fields, particularly in enhancement for sustainability, has gained momentum. This review meticulously explores BC's role in sustainable composites, focusing on geopolymers and alkali-activated binders through a comprehensive examination of existing literature, underscored by bibliometric analysis. This pioneering review, leveraging the PRISMA framework and VOSviewer for bibliometric insights, aims to bridge the research gap in this evolving domain, offering a critical assessment of BC's integration in sustainable construction materials, its challenges, and future research directions. Hence, this pioneering systematic review represents the first-ever exploration within the research domain of BC's applications in geopolymers and alkali-activated materials, marking a foundational step toward understanding its potential and challenges in sustainable engineering practices. [Display omitted] [ABSTRACT FROM AUTHOR]

Natural hazards foster the need for resilience in the built environment, but resilient structures must not interfere with sustainability. The potential trade-offs are increasingly being investigated using performance-based assessments combined with life cycle assessments (LCA) to translate probable building or bridge damage into environmental losses. Leveraging 102 publications intersecting sustainability and resilience in the built environment, this review sheds light on the current methodological challenges and opportunities for integrating natural hazard-induced damage with environmental losses in the built environment. The reviewed literature primarily focused on buildings exposed to seismic hazards, deriving their losses using the best-known LCA mode, attributional LCA. Building and bridge frameworks showed notable methodological distinctions, along with a near absence of consideration of the interactions between climate change and natural hazards or structural vulnerabilities. Based on the findings, 22 opportunities for future research were synthesized. Future research should seek to better assess the total life cycle sustainability of resilient structures by exploring advanced modes of LCA, widening the scope of their assessments, and better integrating uncertainty and sensitivity. Achieving a more sustainable and resilient built environment also requires upcoming research to investigate the practicalities of aligning modeling frameworks, tools, data, and case studies. Addressing these research gaps will assist in anticipating how the built environment can be adapted and shaped to positively contribute to a resilient and sustainable future. [Display omitted] • Shows opportunities to improve measuring sustainability in structural engineering. • Reviews crossings of life cycle assessment with structural performance assessment. • Identifies methodological and practical challenges in tackling the research gaps. [ABSTRACT FROM AUTHOR]

This study investigates the performance of Pervious Concrete (PC) with varying quantities of Natural Coarse Aggregate (NCA) replaced by Waste Tire Rubber (WTR) (5%, 10% and 15% by weight) whereas Silica Fume (SF) (5%, 10% and 15%) and Fly Ash (FA) (10% constant) were employed as substitute for cement. This research aims at optimizing the mix of High Strength Rubberized Pervious Concrete (HSRPC) using Supplementary Cementitious Materials (SCMs), comparing experimental stress-strain graphs with the developed constitutive models and conducting a Life Cycle Assessment (LCA). Physical and mechanical performance of PC were examined using permeability and strength indices. X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) observed microstructural variations and Interfacial Transition Zone (ITZ) development. The use of WTR increased the permeability and decreased the strength indices. The permeability of mixes with 5, 10 and 15% WTR was found to be 4.00, 4.21 and 4.49 mm/s, which were more than control mix permeability. The compressive strength of PC with 5%, 10%, and 15% WTR was determined to be 32.48, 29.29, and 26.94 MPa, respectively, which were lower than control PC compressive strength which was 35.41 MPa. However, the addition of SF and FA enhanced the mechanical properties while causing a decrease in the permeability. Increasing SF content from 0% to 15% enhanced the compressive strength of PC containing 5% WTR, from 32.48 to 40.71 MPa. Developed constitutive models compared the stress-strain response of PC. Life cycle assessment showed that WTR, SF, and FA-based PC reduced the global warming. [Display omitted] • Development of HSRPC using SCM's. • Recycling Waste Tire Rubber to reduce CO 2 emissions. • Silica fume improves the mechanical properties. • Develop constitutive models that characterizes the stress-strain behavior of HSRPC. • Life cycle assessment of rubberized PC. [ABSTRACT FROM AUTHOR]

A teaching approach of programming experiment courses with a new education process is proposed in this study to improve the sustainability of engineering education and extend the accessibility of lab experiments across experiment courses, with the goal of encouraging innovative and scientific thinking among students. The Millikan Oil-Drop experiment combined with Java object-oriented programming is demonstrated as a case study to validate the feasibility and advantages of this teaching approach. The new education process of the experiment course is designed based on Jean Piaget's cognitive development theory, which has high practical potential for popularization among tertiary institutions without additional cost. Additionally, this work discussed the relevance of the general criterion of the Accreditation Board for Engineering and Technology on student outcomes to educational accreditation, further indicating that introducing programming into experiment education can improve students' all-round ability and strengthen the triangular relationship among the three main subjects in tertiary education, namely, students, faculty, and higher educational institutions. This study may serve as an educational guide for teachers and tertiary institutions to pursue innovative and sustainable education. [Display omitted] • Introducing programming to course can enhance sustainability for education. • Programming can help students facilitate the data-processing of experiments. • Introducing programming can better ignite students' interest in the course. • The innovation-oriented approach can help improve the teaching quality. • The approach can make for clean production and sustainable development. [ABSTRACT FROM AUTHOR]

Reprocessing municipal wastes into useful engineering components is one way to reduce their environmental impact. This paper presents a report on an alternative experimental approach to reprocessing common environmental wastes like aluminum scraps, steel shavings, and coconut shells into eco-friendly engineering composite. Equally, response surface analysis was incorporated in the development and validation of predictive models fit for future prediction of response properties. Aluminum scrap was heated into a liquid state and reinforced with recycled steel particles (RSP) and coconut shell ash particles (CSP) at varying proportions. Specimen design involves three group mixes: A, B, and C. Each of the three groups mixes comprised 0, 1, and 2 % RSP at constant dosage, respectively. Meanwhile, each mix was incorporated with 4, 8, and 12 wt % CSP. The microstructural features, physical (porosity, density, and relative density), and mechanical (tensile strength, hardness, elastic modulus, fracture toughness, impact strength, and percentage ductility) properties were appraised. The outcome revealed that the combination of the two reinforcements (RSP and CSP) contributed to microstructural evolution within the specimens. The porosities of the composite specimens were reported to marginally increase with the reinforcement combination. Interestingly, the composite exhibited lighter weight with improved mechanical performance. Mathematical models derived for the response properties were certified fit for future analysis and predictions. Meanwhile, the optimization procedure revealed that the combination of 1.3 % RSP and 6.7 % CSP was suitable for the design of optimal recycled aluminum composites for sustainable engineering designs. The results clarified that the reinforcement particles (RSP and CSP) are low-cost alternatives to synthetic ceramic reinforcements in the aluminum composite." • Sustainable engineering aluminum composites derived from municipal waste. • Inclusion of RSP and CSP yielded improved recycled aluminum composite. • Mechanical performance was dependent on the interactive pattern between RSP and CSP inputs. • Compositional mix of 1.3 % RSP and 6.7 % CSP yielded optimum mechanical performance. [ABSTRACT FROM AUTHOR]

In recent decades, surplus crude glycerol has been generated in large amounts as a waste product of biodiesel production, leading to bottlenecks in the supply chain of the biodiesel industry. This waste glycerol represents an important potential renewable feedstock and platform chemical; however, its purification is often needed for further processing. Advancements towards glycerol purification are being made using sustainable purification techniques aimed at improving the biodiesel industry's environmental footprint. Many studies focussing on various techniques to purify glycerol can be found in the literature; however, very few studies to evaluate the environmental impacts of the purification processes have been reported. This paper provides a critical investigation on the cradle-to-gate life cycle assessment (LCA) of three different processes for purifying crude glycerol, namely, physicochemical treatment and membrane purification (PMP) processes, vacuum distillation purification (VDP) processes and ion exchange purification (IEP) processes having a functional unit (FU) of 1000 kg of purified glycerol. These purification processes were modelled using Aspen plus software v12.1 in combination with Super Pro Designer v13. CCaLC2 (Carbon Calculations over the Life Cycle of Industrial Activities) was used to measure the environmental impacts associated with each process. By following the ISO 14044:2006 methodology and utilising the CCaLC2 tool, seven different types of potential environmental impacts have been investigated, which include carbon footprint, water footprint, acidification, eutrophication, ozone layer depletion, photochemical smog and human toxicity. Sensitivity analysis of the LCA was carried out using the response surface method (RSM) to determine the most effective parameter within the LCA. The total carbon footprint of the PMP, VDP and IEP processes are 3466.82, 1745.72 and 2239.71 kg CO 2 eq. FU−1 respectively. The LCA study determined that waste generated as a result of crude glycerol impurities from the three processes had one of the highest environmental impacts on the overall process. For the PMP and IEP processes, the raw materials used in the physicochemical treatment also contribute significantly to the carbon footprint and other environmental impacts. Lastly, aspects concerning the environmental impacts from the PMP glycerol purification process have been addressed by analysing the raw materials from different sources accompanied by altered waste disposal methods (i.e. the incineration of generated wastes as opposed to landfilling) in an attempt to reduce the overall environmental impacts. For the PMP process, which has the highest carbon footprint, usage of differently sourced raw materials and altered waste disposal treatments resulted in 39% reduction in total carbon footprint and 54% reduction in the total ozone layer depletion. Sensitivity analysis of the LCA shows that the glycerol content within the crude glycerol was the most significant parameter. [Display omitted] • First comparative LCA study on crude glycerol purification processes is presented. • Raw materials and waste generated were the leading causes of environmental burdens. • Membrane separation had the highest environmental impacts followed by ion exchange. • Differently sourced raw materials and altered waste disposal methods reduced the carbon footprint. [ABSTRACT FROM AUTHOR]