Green Engineering Research Articles

A Green Dual Function Engineering Material—Sound Absorption and Heat Insulation Based on Water Hyacinth Fiber and Waste Palm Oil

A Green Dual Function Engineering Material—Sound Absorption and Heat Insulation Based on Water Hyacinth Fiber and Waste Palm Oil

Green catalysis and reaction engineering: An integrated approach with industrial case studies

Green catalysis and reaction engineering: An integrated approach with industrial case studies

Sonochemical parallel synthesis of novel 1,2,3-triazoles utilizing gold-supported titania catalyst

BackgroundA lower carbon society can be achieved with innovative recycling and parallel organic and pharmaceutical synthesis practices that reduce the chemical industry's environmental footprint; this is crucial to fulfilling the principles of green chemistry and engineering. MethodRegioselective azide-alkyne cycloadditions were investigated using heterogeneous catalysts based on gold supported on titania (Au/TiO2) and ultrasonic irradiation. The catalysts were used in the base-free synthesis of 1,2,3-triazoles via azide-alkyne click reactions. The catalyzed azide-alkyne cycloaddition reaction protocol was completed in a short amount of time (5 min) with high product yields in parallel synthesis design Significant findingThe superior catalytic efficacy of Au/TiO2 catalysts for achieving the highest product yield emphasizes the ultimate sympathetic of the catalyst structure and role. The scanning electron microscope (SEM) was used to distinguish the synergetic effect of Au/TiO2 catalysts, and the ultrasound irradiation tool for fresh and spent catalysts. Furthermore, the Heteronuclear Multiple Bond Correlation (HMBC) 2D NMR technique was used as a valuable tool to unambiguously assign the obtained structures.

Applying the 12 Principles of Green Engineering in Low TRL Electronics: A Case Study of an Energy-Harvesting Platform

Energy harvesting has been identified as a key enabling technology for the Internet of Things as it allows a battery-less functioning of electronic devices. While the use of ambient sources of energy is commonly seen as sustainable due to their renewable nature, raw material consumption and recyclability need to be assessed to ensure true sustainability. This is especially relevant in electronics, due to their high complexity stemming from the variety of components and materials in their composition. This work presents the case study of the application of the 12 Principles of Green Engineering to an energy-harvesting platform in the early technology development phase. Specifically, the technological areas of design for disassembly, materials for substitution, fabrication efficiency, and manufacturing processes that enable the use of recycled materials have been evaluated. This has allowed us to identify hazardous raw materials and recommend their substitution. Further recommendations include the adoption of mechanical fixtures to fasten lump components. Additional strategies have been identified but their application has been found out of reach of the technology developers, such as the increase in the manufacturing batch size or the inclusion of solvent recycling, which can only be implemented at larger manufacturing scales. Further strategies, such as the use of recycled Si wafers or dry adhesives as fixtures, represent future solutions for the reduction in the environmental impact which require further R&D efforts from different disciplines. This highlights the need for holistic and multidisciplinary research efforts to fully achieve the circular design.

A green, one-step and general engineering platform for high-adhesion superhydrophobic surfaces

The development of simple, low-cost and universal surface modification strategy toward superhydrophobic materials with high adhesion is greatly desired due to its wide applications. Herein, we developed a one-step and general method to achieve the high-adhesion superhydrophobic transformation of various materials by simply depositing the natural urushiol and 3-aminopropyltriethoxysilane (APTES) in ethanol solution. Owing to the self-polymerization of urushiol and the hydrolysis of APTES, a hierarchical structure could be constructed with multi-layered submicron spheres. The resulting urushiol/APTES coating exhibited a water contact angle of 151.2 ± 3° and an adhesive force as high as 142.7 μN with water benefiting from the hierarchical structure and the long alkyl chains of urushiol. As a result, this high-adhesion superhydrophobic surface could easily realize efficient microdroplet manipulation, hemostasis, and oil/water separation. Moreover, the urushiol/APTES coating showed outstanding stability after repeatedly tore with an adhesive tape for 300 times, ultrasonic treated for 300 s, or immersed in strong acidic or alkaline solutions for 24 h. Based on the easy fabrication, high property, and good stability, this surface modification strategy can be a powerful platform to engineer various materials to be high-adhesion superhydrophobic for wide potential applications.

4th International Conference on Green Environmental Engineering and Technology (ICONGEET2022) November 17-18, 2022 · Seoul, South Korea

Preface The 4th International Conference on Green Environmental Engineering and Technology (IConGEET 2022) was a hybrid conference and physically took place in Seoul, Korea on 17-18th November 2022. IConGEET2022 was jointly organised with the 4th International Conference on Green Engineering and Technology (IConGeTech2022). The conference was organized by the Sustainable Environmental Research Group (SERG), Centre of Excellence Geopolymer and Green Technology (CEGeoGTech), Universiti Malaysia Perlis. The conference received international and local collaboration, support and participation from the National Institute for Research and Development in Environmental Protection (INCDPM) Romania, Ton Duc Thang University, Ho Chi Minh City, Viet Nam as well as local universities in Malaysia.It brought together researchers, practitioners, engineers and students worldwide in hope to extend networking, integrate knowledge and exchange ideas among participants. This year, the theme “Driven Technologies toward Sustainable Environment” is driving exciting breakthroughs to help sustaining our planet. Overcoming the engineering challenges of high performance, interoperability and security is critical to delivering next-generation solutions for decreasing emissions, minimizing waste and preventing pollution. Over 70 distinguish researchers, practitioners, engineers and students from across the country have presented their current and intriguing research in the scope of civil and environmental technologies and management, which evolved around five major areas: water and wastewater technology, green technology, air pollution and climate change, environmental management and protection as well as environmental sustainability and development.The conference has gained incredible success due to collective efforts from the organizing committees, the co-organizers, the reviewers, presenters, and all participants. We would like to thank all the reviewers involved in ensuring each contributed paper were refereed and accepted based on interests, relevance, innovation and pure contribution towards environmental engineering and technology fields. Putting together, the success of the conference is a team effort. I am grateful to all the committee members who worked very hard to make this event a successful one. Finally special thanks go to the Universiti Malaysia Perlis for the continuous support throughout the conference event.List of Editors, Organisers, Committee, Organizing & Technical Committee are available in the pdf.

Lignin valorization: A crucial step towards full utilization of biomass, zero waste and circular bioeconomy

Lignin is an abundant but often overlooked biopolymer. Therefore, its valorization is crucial for achieving the goals of full biomass utilization, zero waste, and a circular bioeconomy. This study proposes a conceptual process framework for effectively valorizing lignocellulose biomass and discusses key steps towards achieving the aforementioned objectives. A holistic green one-pot pretreatment approach to lignocellulose biomass can generate both nutrient-rich hydrolysate (sugar-containing) and lignin-rich solid, which can be further converted into fuels/chemicals and biochar/bio-oil/gas, respectively. This integrated biorefinery approach represents an important strategy for developing a self-sustaining bioprocess industry, consistent with principles of green chemistry and engineering and circular economy concepts. To end with, valorization of lignin not only adds value to biomass, but also has the potential to address waste management and environmental concerns.

The Making of Green Engineers: Sustainable Development and the Hybrid Imagination (Synthesis Lectures on Engineering): A Book Review

“Green engineer” is a connotation that needs to be worked so that the public is more aware that engineers nowadays are humanistic in implementing any related projects and it in line with the Sustainable Development Goals 2030. The Making of Green Engineers: Sustainable Development and the Hybrid Imagination (Synthesis Lectures on Engineering) emphasizes the intersection of sustainable development and engineering education, focusing on the formation of "green engineers." It delves into the role of imagination, creativity, and interdisciplinary thinking in preparing engineers to address environmental and sustainability challenges. The book also examines how engineering education can foster a hybrid imagination, combining technical expertise with a deep understanding of social, environmental, and ethical dimensions. It explores pedagogical approaches, curriculum design, and educational practices that nurture sustainability-oriented mindsets among engineering students. The book emphasizes the importance of interdisciplinary collaboration, systems thinking, and a holistic approach to engineering education. It offers insights into the integration of sustainability principles into engineering curricula and the development of green engineering professionals who can contribute to a more sustainable future. The book is highly recommended as a resource for engineers, students, researchers, or professionals seeking to deepen their understanding of sustainable development and the role of green engineering within it.

Sustainable green reinforcement engineering: High-performance GTRM reinforced composites with interfacial gradient structure

Building reinforcement projects are designed to meet the requirements of modern sustainable development. However, the weak bonding performance of continuous glass fiber textiles to mortar presents a challenge in the manufacturing of GTRM composites, hindering their development and application. In this study, the gradient composite design technique was used to modify the interface transition zone between continuous glass fiber textile and mortar by introducing epoxy resin. This successfully resolved the issue of poor bonding between the continuous glass fiber textile and mortar interface, and promoted effective stress transfer between the two materials. The GTRM composites with an interfacial gradient structure exhibit excellent mechanical properties, including a tensile strength of 8 MPa and an interfacial shear force exceeding 27 KN. In addition, digital image correlation (DIC) was utilized to investigate the growth and development of cracks in GTRM composites, and the failure mechanism of tensile and interfacial shear tests was analyzed. Finally, the externally bonded GTRM composites were subjected to a three-point bending test, which demonstrated a significant improvement in the flexural strength and crack resistance of concrete beams.

ACS launches green chemistry education campaign

Chemistry education is undergoing a transformation. Educators grapple with a growing number of concepts to teach in an undergraduate curriculum, and they are realizing that solving sustainability challenges requires interconnected systems. Some of the most exciting innovations are emerging at the intersection of disciplines, such as computer science and chemistry. Global sustainability goals are reframing corporate strategies, encouraging companies to collaborate, curb pollution, and reduce waste. Advocates want manufacturers to deliver safe chemicals from the start rather than identify and replace problematic chemicals years after they have been on store shelves. Chemistry graduates are entering a world that requires good sustainability practices and skills inspired by the ways successful green chemists and engineers think. People in green chemistry have developed technologies that advance the United Nations sustainable development goals while minimizing unintended consequences. Many universities and educators are responding to the need for knowledge of sustainable practices. But it is

Electro‐membrane reactor: A powerful tool for green chemical engineering

AbstractElectro‐membrane reactors use electro‐membranes for preferentially diffusive/electrophoretic migration or electroosmotic separation of in‐situ reactive products, thereby maximizing the reaction rate and transport efficiencies of the products. These reactors are widely employed in the chemical engineering sectors such as green chemical synthesis, biorefining, electrocatalytic reduction/oxidation, and water treatment. In this review article, we provide an overview of the recent advances in three categories of electro‐membrane reactors in chemical engineering sectors from three categories: (1) Electro‐membrane reactors based on stacked ion‐exchange membranes for resources recovery; (2) Electro‐membrane reactors via Faraday reactions on functional anodes/cathodes for substance transformation; and (3) Closed‐loop chemical reactions and substance separation via coupling of Faraday reactions and stacked membranes. The increasing demand for low‐carbon economy has accelerated the advancement of environmentally friendly chemical engineering and sustainable processes and necessitates the use of electro‐membrane processes. The macro perspective provides a timely reference for researchers and engineers.

Yolk-shell structure synergistic defect engineering for boosting electromagnetic wave absorption in Co9S8@Humins-derived carbon

Exploring new strategies to incorporate the concepts of green chemistry and defect engineering into new architectures to address the problem of severe electromagnetic wave (EMW) pollution is challenging. In this work, by using a by-product of catalytic conversion of biomass as a carbon source, we prepare two-dimensional (2D) Co9S8-coated humins-derived carbon nanomaterials with a yolk-shell structure. The EMW attenuation ability is finally optimized by controlling the morphology and defects of the composite material through the pyrolysis temperature. As expected, with the synergy of conductive loss/interfacial polarization and defects regulating, the composite material achieves a reflection loss (RL) value of −51.4 dB in Ku-band and the effective absorption bandwidth (EAB) can be as high as 5.92 GHz (12.08–18.00 GHz) at 1.8 mm ultra-thin coating thickness. A strong absorption capacity in the low-frequency C-band (6.4 GHz) reaches RL value of −49.9 dB and a thickness of 3.50 mm, which grants it the characteristic of convertible microwave absorption from high frequency to low frequency. Taking account of the facile synthesis and tunable absorption properties, the encouraging findings shed light on exploring waste-turned-microwave absorbents with promising practical applications.

Choline chloride-based deep eutectic solvent as an inhibitor of metalloproteases (collagenase and elastase) in cosmetic formulation.

Green chemistry and engineering are potential alternatives for achieving higher sustainability and lower generation of hazardous compounds in chemical product design, production, and use. Deep Eutectic Solvents (DES) are characterized as green solvents and have become increasingly attractive due to their characteristic design solvents. In this work, two DES (choline chloride (ChCl)/glycerol and ChCl/Urea), aqueous solutions of the DES-forming components, and green tea extracts obtained with DES were used as anti-ageing active in cosmetic products using in vitro tests to inhibit extracellular matrix metalloproteases (such as collagenase and elastase). Finally, the stability of the formulations with DES as a cosmetic active was also evaluated. The results showed that DES based on ChCl/Urea and ChCl/glycerol exhibited remarkable inhibition values of collagenase (91.1 and 92.7%, respectively) and elastase (49.8 and 45.7%, respectively). However, pure urea displayed better inhibition values (66%) for elastase, possibly due to its direct contribution to intramolecular hydrogen bonds. ChCl/glycerol showed remarkable stability in the average cube diameter values, which may indicate no change in the conformation of the micellar structure of the cosmetic formulation. Moreover, the formulation containing this DES remained stable at room temperature. Given the remarkable results, DES can be applied in cosmetic products for anti-ageing purposes.

Efficient protein tagging and cis-regulatory element engineering via precise and directional oligonucleotide-based targeted insertion in plants.

Efficient and precise targeted insertion holds great promise but remains challenging in plant genome editing. An efficient non-homologous end-joining-mediated targeted insertion method was recently developed by combining CRISPR/SpCas9 gene editing with phosphorothioate modified double-stranded oligodeoxynucleotides (dsODNs). Yet this approach often leads to imprecise insertions with no control over the insertion direction. Here, we compared the influence of chemical protection of dsODNs on efficiency of targeted insertion. We observed that CRISPR/SpCas9 frequently induced staggered cleavages with 1-nucleotide 5´overhangs; we also evaluated the effect of donor end structures on the direction and precision of targeted insertions. We demonstrate that chemically protected dsODNs with 1-nucleotide 5´ overhangs significantly improved the precision and direction control of target insertions in all tested CRISPR targeted sites. We applied this method to endogenous gene tagging in green foxtail (Setaria viridis), and engineering of cis-regulatory elements for disease resistance in rice (Oryza sativa). We directionally inserted two distinct transcription activator-like effector binding elements into the promoter region of a recessive rice bacterial blight resistance gene with up to 24.4% efficiency. The resulting rice lines harboring heritable insertions exhibited strong resistance to infection by the pathogen Xanthomonas oryzae pv. oryzae in an inducible and strain-specific manner.

Hybrid eco-friendly coating on bamboo fabric through Taguchi formulations for flame and thermal resistance

The flammability of natural fibers is their main limitation in high-temperature engineering applications, a contemporary issue in the present green engineering sector. Therefore, the current investigation focused on developing fire-resistant natural fibers through surface coating with hybrid biochemicals using the Taguchi approach (L9 orthogonal array). The low-cost and eco-friendly chemicals, chitosan (CTS), sodium bicarbonate (SBC), and ammonium polyphosphate (APP), were utilized by dissolving 3 wt% and 6 wt% of each in an aqueous medium and coating the mixture on bamboo nonwoven fibers (BNFs). The surface chemistry of the coated BNFs were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The effect of the hybrid coating on the flammability and thermal stability of the BNFs were studied. The experimental results indicate that the synergistic effect of the chemicals through the intumescent mechanism and metal bicarbonate effectively improved the flame resistance of BNFs. The results of the vertical burning test of the coated fibers indicated their exceptional self-flame-extinguishment, reaching the V0 level, with excellent thermal stability and almost 40 wt% residue at 700 °C. Overall, the hybrid coat could enhance the flame-resistant properties of natural fibers, thereby overcoming the limitations of natural fibers and making them suitable for use as sub-structural components in engineering applications as reinforcements.

Improving undergraduate graduation chemical design using green techniques based on green engineering principles

Green engineering education is of great significance. The development of the chemical industry has a new direction under the background of engineering back to green engineering and chemistry. The undergraduate graduation chemical design is an important course for the comprehensive application of professional knowledge and bridging to the actual production, and also important support for the cultivation of chemical talent. This paper presents a case in which the improvement of ethyl acrylate process design can be selected as a topic of undergraduate graduation chemical design, which has both an industrial production process foundation that student can learn and engineering design innovation under the guidance of the green engineering concept. After the design study, the results show that the process design of ethyl acrylate supported by new clean catalysis and membrane separation technologies has been improved in reducing process complexity and improving environmental friendliness. Furthermore, the teaching result indicates that the process design reinforces students' green engineering thinking and provides a green engineering teaching format for chemical design.

Non-Destructive Disassembly of Interference Fit under Wear Conditions for Sustainable Remanufacturing

Remanufacturing has been gaining increasing attention in the last few years as a part of green engineering. It is the process of restoring the original specifications of a given product utilizing a combination of new, repaired, and old parts. The present study investigates non-destructive disassembly of an interference fit pin-hub joint to enable the reuse of worn parts with the same loading capacity. The aim is to reduce the disassembly force while preventing plastic deformation and frictional damage on the contact surface to avoid fretting failure and enable further coating. A finite element model of a shaft/hub interference fit was developed, taking into account two cases of damage to the mating parts: deformation and corrosion. The results indicate that thermal disassembly is effective in reducing breaking force by 50% in deformed joints, whereas vibration waves are more suitable for corroded parts with increased friction. In addition, applying a low-frequency oscillation force to the axis of disassembly reduces the pulling out force by 5% and plastic deformation by 99% due to acoustic softening effects. Furthermore, using a heat flux simultaneously with vibration decreases the breaking force by 85%, indicating the higher effectiveness of thermal-aided disassembly and vibration-assisted disassembly in reducing the breaking force of corroded parts with increased friction. This study provides remanufacturing designers with efficient tools to weaken the interference fit and decrease the disconnecting force, ultimately reducing the cost and time required for the disassembly process.

Factors Influencing Cost Performance Improvement on the Concept Of Green Retrofitting High-Rise Offices Using Structural Equationg Modelling-Part Least Square (SEM-PLS)

The increase in energy consumption in the operation of the building construction industry globally has increased by a percentage of 35%, so that this increase can lead to an increase in carbon emissions which was originally at a percentage of 28% to 38%. The concepts of Green Retrofitting, Dynamic Systems and Value Engineering can be researched based on the influence on improving the cost performance of Green Retrofitting in high-rise (existing) office buildings and connected with the Structural Equation Modelling-Partial Least Square (SEM-PLS) analysis model. PLS-SEM is very appropriate to be used in research aimed at developing theories. The results of this study show that in the application of the Green Retrofitting concept in high-rise office buildings using Dynamic Systems and Value Engineering has a significant effect on improving the cost performance of Green Retrofitting and get the most influential factors are Top Management Support, Energy Efficiency, Water Efficiency, Indoor Air Quality, Retrofitting Planning, Retrofitting Initial Costs, Bill Of Quantity, Dynamic System Model Generation, Alternative Material Selection, and Material Cost Reduction

Improved Stability and Catalytic Efficiency of ω-Transaminase in Aqueous Mixture of Deep Eutectic Solvents.

The efficient biosynthesis of chiral amines at an industrial scale to meet the high demand from industries that require chiral amines as precursors is challenging due to the poor stability and low catalytic efficiency of ω-transaminases (ω-TAs). Herein, this study adopted a green and efficient solvent engineering method to explore the effects of various aqueous solutions of deep eutectic solvents (DESs) as cosolvents on the catalytic efficiency and stability of ω-TA. Binary- and ternary-based DESs were used as cosolvents in enhancing the catalytic activity and stability of a ω-TA variant from Aspergillus terreus (E133A). The enzyme exhibited a higher catalytic activity in a ternary-based DES that was 2.4-fold higher than in conventional buffer. Moreover, the thermal stability was enhanced by a magnitude of 2.7, with an improvement in storage stability. Molecular docking studies illustrated that the most potent DES established strong hydrogen bond interactions with the enzyme's amino acid, which enhanced the catalytic efficiency and improved the stability of the ω-TA. Molecular docking is essential in designing DESs for a specific enzyme.

Green Requirement Engineering: Towards Sustainable Mobile Application Development and Internet of Things

Mobile usage statistics show the one thing that cannot be overlooked, which is the overwhelming usage of smartphones. According to the statistics, there are approximately 6.4 billion users of smartphones. Considering the world population, this rate of smart phone usage is more than 80%. Mobile development is the fastest prominent trend, although web development cannot be denied. However, the fact is that mobile platforms are considered cumbersome and complex when it comes to accomplishing requirement engineering processes, especially when mobile applications are combined with the Internet of Things (IoT). These complexities result in barriers to sustainable mobile development. The difficulty and differences occur due to various limitations, either that of mobile devices or others. Some of those from mobile devices include processor, battery, and touch screens, user experience in terms of touch screens, user context, and interactive behaviors. Other limitations include the difference in the software development lifecycle and the difference in the software development process due to inconsistency in user requirements with the aforementioned limited device capabilities. The target objective of this research is to investigate and identify all possible challenges related to mobile applications and connected mobile devices (IoT) while executing the requirement engineering process. This study can further the existing state of knowledge by contributing to the list of challenges faced in the requirement gathering process of mobile application development. Furthermore, it can also help practitioners, specifically those involved in the requirement gathering process, to carefully consider these challenges before executing the requirement engineering process.