Consumption Of Fossil Resources Research Articles

Adsorption–Activation Bifunctional Center of Al/Co‐Base Catalyst for Boosting 5‐Hydroxymethylfurfural Oxidation

AbstractElectrocatalytic conversion of biomass‐derived 5‐hydroxymethylfurfural (HMF) to value‐added 2,5‐furandicarboxylic acid (FDCA) is of great significance in compensating for the rapid consumption of fossil resources. However, it is a challenge to further improve the performance of HMF electrocatalytic oxidation (HMFOR) by synergistic kinetics (active sites) and thermodynamics (adsorption sites). In this work, Al(OH)3/Co(OH)2 is successfully fabricated as an efficient catalyst, and its catalytic mechanism for HMF oxidation is clarified. Extended X‐ray absorption fine structure (EXAFS) analysis demonstrate that electrochemically generated Co3+ is the main catalytic site for HMF oxidation. The HMF equilibrium adsorption capacity of Al(OH)3 reach 57.0 mg g−1, which effectively increase the initial concentration of substrate and promoted the reaction rate. The combined results, based on 24 stable cycles and an FDCA yield retention rate of 98.6% after 180 days, are the highest ever achieved. Additionally, it is shown that this system can oxidize four other biomass‐derived substrates. Therefore, this work provides insight into a hydroxide catalyst that owes its efficiency to synergy between active and adsorption sites.

Towards the vision of going green: The role of different energy research and development investments, urbanization and income in load capacity factor

Environmental sustainability, one of the agendas of the 21st century, is an essential step in the transition to a low-carbon economy in developing countries. The motivation of this study is to investigate the impact of fossil energy research and development investments on environmental quality within the framework of the load capacity curve hypothesis, and urbanization is also added to the model to avoid omitted variable bias. To this end, the Augmented ARDL analysis examines the relationship between economic growth and ecological well-being in Turkiye from 1986 to 2022. The results from the empirical analysis support the accuracy of the load capacity curve hypothesis. Furthermore, it is observed that renewable energy research and development investments, which are the main component of the study, improve environmental quality.On the other hand, it has been found that research and development investments in fossil fuels and urbanization reduce the load capacity factor. Based on the study’s findings, the Turkish government should allocate more research and development budget to transition to a low-carbon economy. Considering Turkiye’s intense fossil resource consumption, the government should plan research and development budget arrangements supported by law regarding energy efficiency.

How to Measure the Greenness of Chemicals? A Case Study on Butadiene Production Applying Green Metrics and Life Cycle Assessment

AbstractThe greenness of naphtha‐ and bioethanol‐based butadiene was compared using green metrics (GM) and life cycle assessment (LCA). GM provide predominantly qualitative results, showing advantages for bioethanol‐based butadiene. LCA indicates benefits of bioethanol‐based butadiene in terms of global warming and fossil resource consumption, but drawbacks in acidification, eutrophication, radiation, land use, ozone depletion, particulate matter, ozone formation, metal depletion, and freshwater consumption. When comparing both assessment approaches used, LCA offers a more comprehensive environmental assessment while GM is limited to a smaller section of the value chain but address additional aspects such as safety of chemicals.

A comparative environmental life cycle assessment of road asphalt pavement solutions made up of artificial aggregates

The construction and maintenance of road pavements entail detrimental impacts on the consumption of resources and damage to the natural environment but also make up an opportunity for the large-scale application of circular economy principles and innovative waste valorisation paths. The present study focuses on developing a comprehensive procedure to evaluate the technical and environmental sustainability of replacing high percentage of limestone aggregates with artificial aggregates from municipal solid waste incineration (MSWI) into hot or cold recycled asphalt mixtures for asphalt pavements.The technical feasibility of the designed mixtures was investigated in terms of the main physical and mechanical properties of both the raw materials and the asphalt mixtures with content of artificial aggregates or sand in the range 25–40 % by mass. The environmental feasibility of the asphalt mixtures was evaluated through the SEM-EDS technique, the analysis of the eluate of the leaching test and the ecotoxicity for living organisms.Afterwards, the life cycle assessment (LCA) was applied to detect the critical spots of the life cycle of 1 m2 of a 6 cm-thick binder layer with high percentage of artificial aggregates or sand built and maintained through 30 years analysis period according to 18 impact category indicators.The main results show that, recycling the artificial aggregates into hot asphalt mixtures has on average a negligible effect on the overall environmental performance of the life cycle, and appears to be detrimental only for the consumption of fossil resources due to the higher optimum bitumen content. Looking at the results for cold mixes, the introduction of the artificial aggregates has an effect on the predicted durability of the asphalt layers, which is maximized in the case of coarse artificial aggregates. Consequent environmental benefits regard the global warming potential, fossil resource scarcity and freshwater eutrophication indicators.

A degradable multi-functional packaging based on chitosan/silk fibroin via incorporating cellulose nanocrystals-stabilized cinnamon essential oil pickering emulsion

In this study, cellulose nanocrystals (CNC) exhibited a higher aspect ratio derived from Rosa roxburghii pomace (RRP), enabling them to effectively carry more charge and consequently form a Pickering emulsion (PE) of cinnamon essential oil (CEO) with enhanced stability. This mixture was then incorporated into a chitosan/silk fibroin (CS/SF) matrix to create an activated food packaging film successfully. Additionally, the cinnamon essential oil - Pickering emulsion (CEO-PE) prepared in this study exhibited superior compatibility with the film substrate. Scanning electron microscopy (SEM) results showed that the Pickering emulsion was uniformly distributed in the CS/SF matrix and formed microstructure-sized holes in the film. The FT-IR results revealed the formation of robust hydrogen bonds between the film components, indicating successful encapsulation of the CEO within the film. Furthermore, the incorporation of CEO-PE enhanced the film's mechanical and thermal stability, reduced the water vapor transmission rate, improved the film's DPPH radical scavenging and bacterial inhibition abilities, and imparted slow-release properties. Moreover, the prepared CS/SF/PE films had good degradation ability, which were basically decomposed by microorganisms within 14 d. And a life cycle assessment revealed that the CS/SF/PE film production reduces fossil resource consumption by more than 68% and global warming by more than 34% compared to film sourced from petroleum. In summary, this research demonstrated that CNC obtained from RRP can be successfully prepared as CEO-PE and combined with CS/SF matrix to prepare active food packaging film, which was promising films for extending the shelf life of fresh fruits.

Characterization of Poly(3-hydroxybutyrate) (P3HB) from Alternative, Scalable (Waste) Feedstocks.

Bioplastics hold significant promise in replacing conventional plastic materials, linked to various serious issues such as fossil resource consumption, microplastic formation, non-degradability, and limited end-of-life options. Among bioplastics, polyhydroxyalkanoates (PHA) emerge as an intriguing class, with poly(3-hydroxybutyrate) (P3HB) being the most utilized. The extensive application of P3HB encounters a challenge due to its high production costs, prompting the investigation of sustainable alternatives, including the utilization of waste and new production routes involving CO2 and CH4. This study provides a valuable comparison of two P3HBs synthesized through distinct routes: one via cyanobacteria (Synechocystis sp. PCC 6714) for photoautotrophic production and the other via methanotrophic bacteria (Methylocystis sp. GB 25) for chemoautotrophic growth. This research evaluates the thermal and mechanical properties, including the aging effect over 21 days, demonstrating that both P3HBs are comparable, exhibiting physical properties similar to standard P3HBs. The results highlight the promising potential of P3HBs obtained through alternative routes as biomaterials, thereby contributing to the transition toward more sustainable alternatives to fossil polymers.

Environmental sustainability assessment of different end-of-life scenarios for the pulper rejects produced in the paper recycling process

Resource recovery from wastes through recycling processes promotes near-zero-waste residue business models and supports the circular economy's goals by facilitating the closure of loops in industrial systems and reducing energy and resource consumption as well as pollutant emissions. However, the approach is sustainable only when the waste can be valorized, and the environmental impact of the recycling is lower with respect to other end-of-life (EOL) scenarios. Due to the diversity and complexity of wastes streams, these aspects need to be evaluated on a case-by-case basis.This study focuses on a mechanical recycling process for pulper rejects, a mixed waste stream generated during recycled paper production, with two aims: (1) to define a feasible mechanical recycling process and (2) to evaluate its environmental performance through life cycle assessment (LCA) compared to the most common EOL treatments, such as incineration with energy recovery and landfilling. ReCiPe 2016 H method was used to estimate the environmental impacts of all scenarios, adopting both midpoint and endpoint approaches, on a functional unit (FU) defined as 1000 kg of pulper rejects. The LCA results indicate that the pulper rejects recycling is always preferable to landfilling across all impact categories considered. On the contrary, in comparison to incineration, the best environmental option depends on the specific impact category considered. In particular, recycling is the best EOL alternative in terms of impacts on global warming, with an impact 33 % lower, but it is not the most sustainable one in terms of fossil resource consumption, mainly due to the amount of energy required during all steps of the recycling process, while allowing the recovery of materials that would otherwise be lost. Currently, it is not possible to identify an overall ‘winner’ between incineration with energy recovery and recycling for the pulper rejects because the most environmentally sound alternative varies depending on the priority given to different environmental issues. Therefore, further improvements of the pulper rejects recycling pathway performances are required to make the process even more efficient and competitive.

Recent Progress on the 3D Printing of Dynamically Cross‐Linked Polymers

AbstractThe utilization of dynamic cross‐linking represents a highly promising approach in addressing the escalating issues of plastic pollution and fossil resource consumption. Despite being extensively investigated over the past decade, various dynamically cross‐linked polymers (DCPs) predominantly remain confined to the realm of academic research. To serve as a valuable material for practical application, advanced processing is always essential for all kinds of materials. 3D printing (3DP) enables the creation of intricate shapes layer‐by‐layer without relying on molds, thus the integration of 3DP techniques with DCPs holds significant potential to enhance and expand the practical applicability of DCPs. Here, an overview of the fundamental principles underlying DCPs compatible 3DP techniques are provided, namely photocuring 3DP, extrusion‐based 3DP, and laser sintering‐based 3DP. Additionally, a comprehensive summary of representative research works that specifically focus on the application of DCPs in each respective 3DP technique is presented. The performance and dynamic mechanism involved in the corresponding printing process are thoroughly discussed and comprehensively reviewed. Finally, the existing challenges and issues pertaining to further enhancing 3D printability, performance, efficiency, etc., are extensively deliberated upon, while proposing potential directions to address these concerns.

Investigation on the Influence of Process Parameters on the Mechanical Properties of Extruded Bio-Based and Biodegradable Continuous Fiber-Reinforced Thermoplastic Sheets.

The use of bio-based and biodegradable matrix materials in fiber-reinforced polymers (FRPs) is an approach to reduce the consumption of fossil resources and the amount of polymer waste. This study aims to assess the influence of the process parameters on the resulting mechanical properties of extruded bio-based and biodegradable continuous fiber-reinforced thermoplastics (CFRTPs) in the form of sheets. Therefore, the impregnation temperature during the production of PLA/flax fiber composites is varied between 220 °C and 280 °C, and the consolidation pressure, between 50 bar and 90 bar. A design of experiments approach is used. Fiber contents of 28.8% to 34.8% and void contents of 6.8% to 15.5% are determined for the composites by optical measurements. To assess the mechanical properties, tensile tests are performed. Using the evaluation software Minitab, a strong negative influence of the consolidation pressure on the tensile modulus and the tensile strength is observed. Increasing the pressure from 50 bar to 90 bar results in a reduction in the tensile modulus of 50.7% and a reduction in the tensile strength of 54.8%, respectively. It is assumed that this is due to fibers being damaged by the external force exerted onto the materials during the consolidation process in the calender. The influence of the impregnation temperature on the mechanical properties cannot be verified.

Unveiling Sustainable Potential: A Life Cycle Assessment of Plant-Fiber Composite Microcellular Foam Molded Automotive Components.

The development and utilization of new plant-fiber composite materials and microcellular foam molding processes for the manufacturing of automotive components are effective approaches when achieving the lightweight, low-carbon, and sustainable development of automobiles. However, current research in this field has mainly focused on component performance development and functional exploration, with a limited assessment of environmental performance, which fails to meet the requirements of the current green and sustainable development agenda. In this study, based on a life cycle assessment, the resource, and environmental impacts of plant-fiber composite material automotive components and microcellular foam molding processes were investigated. Furthermore, a combined approach to digital twinning and life cycle evaluation was proposed to conduct resource and environmental assessments and analysis. The research results indicate that under current technological conditions, resource and environmental issues associated with plant-fiber composite material automotive components are significantly higher than those of traditional material components, mainly due to differences in their early-stage processes and the consumption of electrical energy and chemical raw materials. It is noteworthy that electricity consumption is the largest influencing factor that causes environmental issues throughout the life cycle, especially accounting for more than 42% of indicators such as ozone depletion, fossil resource consumption, and carbon dioxide emissions. Additionally, the microcellular foam molding process can effectively reduce the environmental impact of products by approximately 15% and exhibits better overall environmental performance compared to chemical foaming. In future development, optimizing the forming process of plant-fiber composite materials, increasing the proportion of clean energy use, and promoting the adoption of microcellular foam injection molding processes could be crucial for the green and sustainable development of automotive components.

Mode of innovative green production for concrete engineering: life cycle assessment of accelerators prepared from aluminum mud wastes.

In this study, two types of liquid alkali-free accelerators were prepared by aluminum sulfate (AF1) and aluminum mud wastes (AF2), and the life cycle assessment (LCA) in the preparation of AF1 and AF2 was compared. The LCA was considered from cradle to gate including raw materials used, transportation, and accelerator preparation based on the method ReCiPe2016. The results indicated that AF1 had a higher environmental impact in all midpoint impact categories and endpoint indicators than that of AF2, and AF2 reduced 43.59% emission of CO2, 59.09% emission of SO2, 71% consumption of mineral resources, and 46.67% consumption of fossil resources than that of AF1 respectively. As an environment-friendly accelerator, AF2 had a better application performance than traditional accelerator AF1. When the dosage of accelerators was 7%, the initial setting times of cement pastes containing AF1 and AF2 were 4 min 57 s and 4 min 04 s respectively, the final setting times of cement pastes containing AF1 and AF2 were 11 min 49 s and 9 min 53 s respectively, and the compressive strengths at 1 d of mortars containing AF1 and AF2 were 7.35 MPa and 8.33 MPa respectively. This study aims to provide technical feasibility and environmental impact assessment for exploring new avenues of preparing environment-friendly liquid alkali-free accelerators with aluminum mud solid wastes. It has great potential in reducing carbon and pollution emissions and has a greater competitive advantage due to great application performance.

In Situ Synthesis of NiFeLDH/A-CBp from Pyrolytic Carbon as High-Performance Oxygen Evolution Reaction Catalyst for Water Splitting and Zinc Hydrometallurgy.

Nickel-iron-layered double hydroxide (NiFeLDH) is one of the promising catalysts for the oxygen evolution reaction (OER) in alkaline electrolytes, but its conductivity limits its large-scale application. The focus of current work is to explore low-cost, conductive substrates for large-scale production and combine them with NiFeLDH to improve its conductivity. In this work, purified and activated pyrolytic carbon black (CBp) is combined with NiFeLDH to form an NiFeLDH/A-CBp catalyst for OER. CBp not only improves the conductivity of the catalyst but also greatly reduces the size of NiFeLDH nanosheets to increase the activated surface area. In addition, ascorbic acid (AA) is introduced to enhance the coupling between NiFeLDH and A-CBp, which can be evidenced by the increase of Fe-O-Ni peak intensity in FTIR measurement. Thus, a lower overvoltage of 227 mV and larger active surface area of 43.26 mF·cm-2 are achieved in 1 M KOH solution for NiFeLDH/A-CBp. In addition, NiFeLDH/A-CBp shows good catalytic performance and stability as the anode catalyst for water splitting and Zn electrowinning in alkaline electrolytes. In Zn electrowinning with NiFeLDH/A-CBp, the low cell voltage of 2.08 V at 1000 A·m-2 results in lower energy consumption of 1.78 kW h/KgZn, which is nearly half of the 3.40 kW h/KgZn of industrial electrowinning. This work demonstrates the new application of high-value-added CBp in hydrogen production from electrolytic water and zinc hydrometallurgy to realize the recycling of waste carbon resources and reduce the consumption of fossil resources.

Fe-Ni bimetallic nanoparticles encapsulated into nanofibrous carbon microspheres as a catalytic nanoreactor for highly selective hydrogenation of 5-hydroxymethylfurfural to 2,5-dihydroxymethylfuran or 2,5-dihydroxymethyltetrahydrofuran

BackgroundThe highly efficient conversion of renewable biomass-derived platform compounds to high value-added chemicals is one of the most promising solution to the current rapid consumption of fossil resources. MethodsNanofibrous and porous carbon microspheres (NPCMs) were developed from chitin biomass and used to encapsulate Fe-Ni bimetallic nanoparticles for the formation of a novel catalytic nanoreactor (Fe-Ni/NPCMs), which was then used for the selective hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-dihydroxymethylfuran (DHMF) or 2,5-dihydroxymethyltetrahydrofuran (DHMTHF). Significant findingsThe NPCMs consisted of N-doped carbon nanofibers with a high surface area. The Fe-Ni bimetallic nanoparticles were uniformly dispersed on the carbon nanofiber surfaces of the Fe-Ni/NPCMs, resulting in abundant catalytic sites and excellent catalytic performance. Importantly, the Fe-Ni/NPCMs showed highly-selective hydrogenation of HMF to DHMF or DHMTHF with high yields of 93.6% or 94.9% through simply modulating the reaction conditions. Increasing the zero valent iron (Fe0) content in the Fe-Ni/NPCMs significantly promoted the DHMTH selectivity from HMF hydrogenation. Moreover, the Fe-Ni/NPCMs presented high stability and recyclability, and thus they are applicable to other biomass conversions. Therefore, Fe-Ni/NPCMs have promising industrial application in the production of high value-added chemicals from biomass-derived feed-stocks.

Transition into Net-Zero Carbon Community from Fossil Fuels: Life Cycle Assessment of Light-Driven CO2 Conversion to Methanol Using Graphitic Carbon Nitride

Direct conversion of waste CO2 into CH3OH by solar irradiation has emerged as the most enthralling alternative to conventional steam methane reforming, which reduced the concentration of greenhouse gases and the consumption of fossil resources. A cradle-to-gate life cycle assessment was carried out to assess the environmental feasibility of implementing the current g-C3N4-based photocatalytic CO2 reduction system based on 1 kg CH3OH production. It was observed that the emerging photocatalytic CH3OH system induced 68 and 53% less carbon footprint and fossil usage, respectively, in producing the same amount of CH3OH as compared to the conventional approach. The CO2 reduction reaction step was identified as the main contributor in photocatalytic system, which accounted for more than 50% of the total environmental impact scores. In the conventional system, the score points of global warming and fossil depletion contributed the most by the product purification and desulfurization step, respectively. In addition, sensitivity analysis manifested that the lowest environmental burden of 46.50 kg of CO2 equiv carbon emission and 15.27 kg oil equiv fossil consumption was obtained in the photocatalytic CH3OH system upon replacing fossil-based energy with hydro-powered electricity. These results suggest a potent replacement of the incumbent industry system for the amelioration of climate benefits and resource conservation with the advanced development of the photocatalytic system.

Boosted Mechanical Properties of Polyamide 11 Tube Originated from the Hierarchical Architecture Manipulation by Helical Flow Field

Polyamide 11 (PA11) is a biobased polymer originated from the renewable plant-based resources and thus holds promising potential in reducing the consumption of limited fossil resources and protecting the environment. Compared to the commonly investigated polyolefin, the flow manipulation strategy for improving the mechanical properties of PA11 still remained a huge challenge because the strong intermolecular interactions elevated the difficulty of stretching the polar polymer chains. Herein, a helical flow was introduced in the PA11 tube extrusion by superposing a hoop flow from mandrel rotation onto an axial flow. Then, the helical flow-induced hierarchical architecture was investigated to reveal the effect of intermolecular interactions on the orientation and crystalline structure. Limited by strong hydrogen bonds between the amide groups, the PA11 chains were not stretched sufficiently to form anisotropic shish-kebab crystals but assembled into a helically aligned configuration in amorphous regions, similar to that in natural materials, endowing the as-prepared tube with enhanced hoop kink resistance and axial compression properties which were favorable to the practical application of the thin-wall tube. This study not only can provide a feasible way to tailor the mechanical properties of the PA11 tube by constructing a special multidimensional flow but also is beneficial to the fundamental understanding on the flow-induced crystallization mechanism of polar polymers with strong intermolecular interactions.

A sustainable thermochemical conversion of animal biomass to N-heterocycles

The production of high-valued organonitrogen chemicals, especially N-heterocycles, requires artificial N2 fixation accompanied by the consumption of fossil resources. To avoid the use of these energy- and resource-intensive processes, we develop a sustainable strategy to convert nitrogen-rich animal biomass into N-heterocycles through a thermochemical conversion process (TCP) under atmospheric pressure. A high percentage of N-heterocycles (87.51%) were obtained after the TCP of bovine skin due to the abundance of nitrogen-containing amino acids (e.g., glycine, proline, and l-hydroxyproline). Animal biomass with more diverse amino acid composition (e.g., muscles) yielded higher concentrations of amines/amides and nitriles after TCP. In addition, by introducing catalysts (KOH for pyrrole and Al2O3 for cyclo-Gly–Pro) to TCP, the production quantities of pyrrole and cyclo-Gly–Pro increased to 30.79 mg g−1 and 38.88 mg g−1, respectively. This approach can be used to convert the significant animal biomass waste generated annually from animal culls into valued organonitrogen chemicals while circumventing NH3-dependent and petrochemical-dependent synthesis routes.Graphical

Progress of social assessment in the framework of bioeconomy under a life cycle perspective

The bioeconomy is positioned as a sustainable pathway to address the climate crisis and decrease the consumption of fossil resources. Life cycle methodologies are recognised as useful tools for assessing sustainability issues of production and consumption patterns. Nevertheless, the Social Life Cycle Assessment (S-LCA) methodology is less explored despite its potential, although it is true that social sustainability assessment in promoting bioeconomy strategies requires more attention. This study describes the state of the art of the S-LCA methodology under the bioeconomy framework, critically analysing the main procedural and practical issues of its implementation, and the eventual specificities, as well as providing some of the challenges for future studies. This review highlights methodological weaknesses that require further research, related to the definition of system boundaries and cut-off criteria, the method of impact assessment, and the selection of societal issues and stakeholders, as well as uncertainty, among others. In addition, particularities of the bioeconomy in the life perspective were noted, such as multifunctionality and allocation issues of bio-based products, as well as the strong interest in biofuel production systems. Therefore, more efforts are desirable to address the diversity of challenges towards the progress of the S-LCA method in line with other life cycle approaches (environmental and economic). However, the updated S-LCA Guidelines represent a useful and valuable starting point on the way towards a comprehensive (i.e., diverse social concerns) and standardised social assessment under a life cycle perspective.

An example to illustrate the role of R&D in the emerging industrial hydrogen economy

The global warming awareness, the reduction of fossil resources, the demand for well-being of industrialized societies, geopolitical upheavals and tomorrow perhaps the biodiversity crisis are powerful drivers to forster a change in the means of production and use of energy. In this context, the idea of a “hydrogen economy” emerged at the turn of the century (Brandon and Kurban, 2017) around the relatively new notion of hydrogen as an “energy carrier”. However, all concepts even if very appealing, become concrete achievements. Conditions for the emergence of an “industrial sector” (Stoffaës, 1980) need to be fulfilled, i.e. at least a viable market, robust technologies for production and use technologies and logistics. In the following, the authors attempt to illustrate the conditions for the emergence of an industrial hydrogen-energy sector, in particular the role of R&D that underpins this process. There is first a cognitive barrier. The physico-chemical properties of hydrogen are particularly well known, and means are available to produce it in large quantities (Brandon and Kurban, 2017). The risks are also known but are well under control in the industry. Socio-economic actors may find this reassuring. The second element is societal. Mature industrial sectors represent considerable fixed capital. Even if research has already shown that it would be possible to produce hydrogen differently, there is little reason for these well-established sectors to evolve without additional incentives. The societal “drivers” mentioned above (climate change, depletion of fossil resources, etc.) have prompted Europe to take increasingly restrictive measures on the consumption of fossil resources (carbon tax, anti-pollution standards). The effect is a paradigm shift, particularly for the mobility sector, which is now investing heavily in electric and hydrogen vehicles. The third element is techno-economic. If hydrogen appears as a possibility, it is because preliminary R&D work has developed key technologies: fuel cells, very high pressure tanks and created “demonstrators”. But the production technologies and the supply chain need to be developed. European regulations require the provision of hydrogen (produced in a renewable way) up to 3T per day every 150 km by 2030 (European parliament; 2021), which suggests a tight network of the territory. One option is local production either through water electrolysis or biomass gasification. QAIROS Energies identified a business model that can link significant local hydrogen use to favorable agricultural conditions. Technologies are available to grow the biomass, to pyrolyze/ gasify it and to turn the gases in hydrogen (Cao et al., 2020), which offers a range of possible processes. The economic equilibrium requires that the gasification yield be 75-125 kg H2 / ton of biomass with a minimum consumption of utilities (water, energy, consumables,...) and requires also as little residues and toxics as possible, the gas treatment costs being quickly prohibitive. Based on these constraints, QAIROS-Energies set up an R&D team aggregating skills in agronomy to select the most suitable crops, biomass pre-treatment (drying, grinding) and pyrogasification and gas treatment. The objective is to remove the obstacles and to demonstrate the feasibility of the project. For the pyro-gasification and gas treatment steps, a pilot was quickly set up (Figure 4) showing a certain resemblance to the future industrial units, which goes beyond academic habits.

Synthesis, characterization and crystallization kinetics of a bio-based, heat-resistance nylon 5T/10T.

The rapid consumption of fossil resources and its adverse impact on the environment require the use of bio-based materials to replace petrochemical products. In this study, we present a bio-based, heat-resistant engineering plastic, poly(pentamethylene terephthalamide) (nylon 5T). To address the issues of the narrow processing window and difficulty in melting processing of nylon 5T, we introduced more flexible decamethylene terephthalamide (10T) units to create a copolymer, nylon 5T/10T. The chemical structure was confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (13C-NMR). We investigated the influence of 10T units on the thermal performance, crystallization kinetics, crystallization activation energy, and crystal structures of the copolymers. Our results demonstrate that the crystal growth mode of nylon 5T is a two-dimensional discoid growth pattern, while nylon 5T/10T exhibits a two-dimensional discoid or three-dimensional spherical growth pattern. The melting temperature, crystallization temperature, and crystallization rate first decrease and then increase, and crystal activation energy first increases and then decreases as a function of 10T units. These effects are attributed to the combined impact of molecular chain structure and polymer crystalline region. Bio-based nylon 5T/10T shows excellent heat resistance (melting temperature > 280 °C) and a wider processing window than nylon 5T and 10T, which is a promising heat-resistant engineering plastic.

Lignin-First Biorefinery for Converting Lignocellulosic Biomass into Fuels and Chemicals

Driven by the excessive consumption of fossil resources and environmental pollution concerns, a large amount of biorefinery research efforts have been made for converting lignocellulosic biomass into fuels and chemicals. Recently, a strategy termed “lignin-first,” which allows for realizing high-yield and high-selectivity aromatic monomers, is regarded as one of the best prospective strategies. This review summarizes recent research advances in lignin-first biorefinery, starting from the raw lignocellulose through lignin-first processing and moving to downstream processing pathways for intermediate compounds. In particular, for the core purpose of producing liquid fuels, the corresponding downstream processing strategies are discussed in detail. These are based on the structural properties of the intermediates derived from lignin-first biorefinery, including the catalytic conversion of lignin and its derivatives (aqueous phase system and pyrolysis system) and the cascade utilization of carbohydrate residues (fermentation, pyrolysis, and hydrothermal liquefaction). We conclude with current problems and potential solutions, as well as future perspectives on lignin-first biorefinery, which may provide the basis and reference for the efficient utilization of lignocellulosic biomass.