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Owing to the enormous consumption of petroleum products and their environmental polluting nature, attention has been given to seeking alternative resources for the development of sustainable products. Biomass is a renewable source that can be converted to a variety of fuels and chemicals by different approaches, which are the best replacements for traditional petroleum‐derived products. Pyrolysis is a process in which chemical bonds of biomass macromolecules such as cellulose, hemicellulose, and lignin, are fractured into small molecular intermediates under high pressure, and results bio‐oil, biochar, and fuel gases as desired products. Of these pyrolysis products, bio‐oil is the primary product that usually contains large amounts of oxygen and nitrogen compounds that hinder its application potential. Catalytic pyrolysis is a beneficial method that is reported to alter the constituents and quality of bio‐oil and to upgrade them for diverse applications. Catalytic hydropyrolysis and copyrolysis of biomass are an alternative approaches to overcome the drawbacks raised toward product formation in the pyrolysis process. Layered double hydroxides (LDH) and their derived forms are well‐known catalytic/catalytic support materials for various chemical reactions due to their superior properties, such as easy preparation, thermal stability, and tuneable acid/base properties. This review summarizes the progress in the utilization of as‐synthesized LDH and their modified forms such as mixed metal oxides and functionalized/composite materials as active catalysts for the pyrolysis of various biomass sources. Review of layered double hydroxides (LDH)‐derived materials as catalysts for thermal and/or solar‐assisted pyrolysis (including hydropyrolysis and copyrolysis) of biomass to produce high‐quality bio‐oil.

This study analyzes energy supply and demand‐side management strategies to increase the renewable energy share in a distributed energy system (DES), which includes demand response (DR) options and different renewable energy sources (RES) and energy storage systems (ESS). To analyze the least costs for increasing the renewable energy share by integrating the DR, RES, and ESS, four scenarios of the DES were generated. Then, a new optimization model was proposed to identify the optimal design and operation strategies, which includes maximizing the profit as an objective function subject to various constraints, such as technical capacity and electricity price. To illustrate the capability of the proposed model, this study presented a case study of the DES for the residential sector of Jeju Island, Korea. The results showed that the optimal scenario, involving the integration of the DR, RES, and ESS, shows 0.115 $/kW hr of the levelized cost of electricity and 10% of renewable energy share, which correspond to 32.7% and 31.5% improvement, respectively, compared to the baseline. Additionally, the practical strategies to meet the Korean target of the high‐share RES were discussed through a sensitivity analysis of major external factors, such as carbon tax, incentives, and the electricity trading price in electricity markets.

The surge in global plastic production, reaching 400.3 million tons in 2022, has exacerbated environmental pollution, with only 11% of plastic being recycled. Catalytic recycling, particularly through hydrogenolysis and hydrocracking, offers a promising avenue for upcycling polyolefin plastic, comprising 55% of global plastic waste. This study investigates the influence of water on polyolefin depolymerization using Ru catalysts, revealing a promotional effect only when both metal and acid sites, particularly Brønsted acid site, are present. Findings highlight the impact of Ru content, metal-acid balance, and their proximity on this interaction, as well as their role in modulating the isomerization process, affecting product selectivity. Additionally, the interaction facilitates the suppression of coke formation, ultimately enhancing catalyst stability. A comprehensive techno-economic and life cycle assessment underscores the viability and environmental benefits of the process, particularly in the presence of water. These insights advance understanding and offer strategies for optimizing polyolefin plastic recycling processes. Catalytic hydrogenolysis and hydrocracking present a promising approach for upcycling polyolefin plastics. Here, the authors highlight the role of water in catalytic plastic upcycling, emphasizing that catalysts with an optimal metal-acid balance significantly improve polyethylene depolymerization when water is present.

The development of technologies for utilizing biomass has attracted attention because biomass can be produced sustainably worldwide. Biomass‐derived 2‐methyltetrahydrofuran (MTHF), which is a promising alternative to gasoline, has great market potential and a growing demand. However, in conventional biomass conversion processes, the minimum selling price (MSP) of biochemicals is not economically acceptable. Co‐production of biochemicals can increase the economics of biomass utilization. Herein, we developed a process for co‐producing MTHF and 1,4‐pentanediol (1,4‐PDO) from lignocellulosic biomass. After biomass fractionation, cellulose and hemicellulose were converted to levulinic acid (LA), and lignin was used for heat and electricity generation. LA was then converted to γ‐valerolactone (GVL). As a platform material for co‐production, GVL was converted into MTHF and 1,4‐PDO in each subsystem. The split ratio of GVL was controlled to efficiently produce MTHF and 1,4‐PDO according to market conditions. Additionally, we performed a techno‐economic and life‐cycle assessment (TEA and LCA, respectively) for the developed process. The MSP of MTHF was calculated based on the TEA results, and the environmental impacts were quantitatively calculated based on the LCA results. We performed heat integration using pinch analysis and then reduced the energy requirement of the proposed process. The key cost drivers and environmental factors of the proposed process were identified via sensitivity analyses. Consequently, during the processing of 2000 ton/day of corn stover (raw material of lignocellulose), the MSP of MTHF was calculated as $2.64/GGE (gasoline equivalent), and representative environmental impacts such as climate change and fossil depletion were calculated as −0.296 kg CO2 eq and − 0.056 kg oil eq, respectively. As a result, we can increase the economics of commercial production of MTHF and 1,4‐PDO with environmental sustainability. The proposed process can serve as a potential solution to the growing demand for the need for more sustainable biomass utilization. 2‐Methyltetrahydrofuran (MTHF) and 1,4‐pentanediol (1,4‐PDO) were produced from biomass, and the techno‐economic assessment (TEA) and life‐cycle assessment (LCA) were performed for the developed process.

Globally, 89% of post-consumer plastic waste is landfilled or incinerated, exacerbating environmental pollution, while less than 0.1% is chemically recycled. Polyolefin plastics, nearly half of global plastic production, can be converted into liquid fuels via hydrogenolysis or hydrocracking but require external hydrogen gas. Here, we report a tandem catalytic process combining decalin dehydrogenation with polyethylene hydrocracking, eliminating the need for external hydrogen by using decalin as a liquid organic hydrogen carrier. Among several Pt/zeolite catalysts evaluated, a bifunctional Pt/HZSM-5 catalyst is identified as the most effective, achieving high PE conversion and selectivity toward liquid fuels. Comprehensive techno-economic and life-cycle assessments are conducted for three configurations: a one-step tandem reaction that directly integrates decalin utilization, a two-step process where dehydrogenation and hydrocracking occur sequentially under hydrogen-rich conditions, and an H 2 -direct process that supplies hydrogen externally. The results demonstrate that utilizing in situ-generated hydrogen from decalin significantly enhances both economic viability and environmental performance compared to conventional external hydrogen methods, with the one-step tandem approach emerging as the most efficient and sustainable pathway. This tandem catalytic system provides a sustainable and economically viable pathway for upcycling abundant polyolefin waste into valuable liquid fuels, advancing circular economy goals and mitigating plastic pollution. Most plastic waste is landfilled, and polyolefin recycling needs external H₂. This work couples decalin dehydrogenation with polyethylene hydrocracking, using in situ H₂ to yield liquid fuels efficiently, improving both economic and environmental sustainability.

Steam methane reforming (SMR) process is regarded as a viable option to satisfy the growing demand for hydrogen, mainly because of its capability for the mass production of hydrogen and the maturity of the technology. In this study, an economically optimal process configuration of SMR is proposed by investigating six scenarios with different design and operating conditions, including CO2 emission permits and CO2 capture and sale. Of the six scenarios, the process configuration involving CO2 capture and sale is the most economical, with an H2 production cost of $1.80/kg-H2. A wide range of economic analyses is performed to identify the tradeoffs and cost drivers of the SMR process in the economically optimal scenario. Depending on the CO2 selling price and the CO2 capture cost, the economic feasibility of the SMR-based H2 production process can be further improved.

The depletion of fossil fuels and environmental pollution (e.g., greenhouse gas emissions) through the combustion of fossil fuels have stimulated studies on new technologies able to curtail the energy consumption of existing fractionation units. In this regard, heat pumps have garnered substantial attention due to their potential to improve the process energy efficiency. This study aims to provide extensive economic analysis and environmental impact assessment of the application of heat pumps under different conditions and scenarios. For this purpose, we first selected three important conditions: feed composition, plant capacity, and fuel price. Then, we performed a range of analyses to identify the major costs and environmental drivers. The economics and environmental impact of heat pump-assisted distillation was investigated and compared with those of conventional distillation.

The biological production of ethanol from ethane for the utilization of ethane in natural gas was investigated under ambient conditions using whole-cell methanotrophs possessing methane monooxygenase. Several independent variables including ethane concentration and biocatalyst amounts, among other factors, were optimized for the enhancement of ethane-to-ethanol bioconversion. We obtained 0.4 g/L/h of volumetric productivity and 0.52 g/L of maximum titer in optimum batch reaction conditions. In this study, we demonstrate that the biological gas-to-liquid conversion of ethane to ethanol has potent technical feasibility as a new application of ethane gas.

Global interest in the recycling of precious metals (PMs) in various industrial sectors has spurred the exploration of high‐performance PM adsorbents. Unfortunately, many adsorbents exhibit unsatisfactory PM adsorption performance and require complex fabrication protocols and toxic chemicals. Hence, further development of simple, efficient, and eco‐friendly adsorbents is necessary. Herein, poly(vinyl chloride) (PVC) waste plastics are simply transformed into high‐performance PM adsorbents via benign solvent treatment and hydrazination. The resultant hydrazine‐functionalized PVC (h‐PVC) plastic can effectively recover gold, palladium, and platinum from real‐world leachates owing to its combined reduction and chemisorption mechanisms. The PM‐adsorbed h‐PVC plastic can be regenerated, calcined into high‐purity PMs, or directly employed as a catalyst, demonstrating its practical feasibility. Techno‐economic and life‐cycle assessments reveal that the h‐PVC plastic‐utilizing industrial‐scale recovery of gold from electronic waste is cost‐competitive and environmentally advantageous. The strategy supports environmental and sustainable technologies by enabling the sustainable maintenance of carbon and PM resources and provides an efficient and sustainable method for fabricating advanced adsorbent materials. Poly(vinyl chloride) waste plastics are simply transformed into high‐performance precious metal (PM) adsorbents via a facile and green hydrazine‐functionalization process. The resultant adsorbent effectively and selectively recovers PM from real‐world leachates via its combined chemisorption and reduction mechanisms. Its practical feasibility and potential for industrial‐scale application are also comprehensively demonstrated.

The efficient recycling of poly(ethylene terephthalate) and poly(butylene terephthalate), the most extensively produced plastics, is essential for reducing global carbon emissions and the current dependence on fossil resources. However, the chemical recycling of polyesters primarily involves polymer‐to‐monomer and monomer‐to‐polymer processes, resulting in significant greenhouse gas emissions owing to significant electricity and fuel consumption. Herein, this research reports a simple and efficient one‐pot polymer‐to‐polymer upcycling process that directly converts these two polyester wastes into biodegradable thermoplastic poly(ether ester)s using poly(tetramethylene ether) glycol (PTMG). The synthesized series of poly((ET‐co‐BT)‐mb‐PTMG) (PEBTG) exhibit a maximum tensile strength of 68 MPa, with 85% weight loss after 20 weeks in composted soil. Techno‐economic analysis and life cycle assessment indicate that PEBTG is more cost‐competitive and environmentally beneficial than currently existing plastics derived from fossil fuels, such as polypropylene and polybutylene adipate terephthalate. Once de‐risked, the proposed upcycling strategy for polymer waste can be extended to expedite the development of a sustainable plastic economy. One‐pot melt transesterification upcycles post‐consumer PET and PBT with PTMG into biodegradable TPEEs featuring randomized polyester chains, tunable mechanical properties, and accelerated biodegradation. TEA and LCA analyses show competitive cost and reduced carbon emissions relative to PP and PBAT.