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[Display omitted] • Microwave-assisted pyrolysis is a promising method for biomass/waste valorisation. • Life cycle analysis shows reduced energy consumption, low global warming potential. • Innovations in reactor design and operation parameters aids in cost reduction. Microwave-assisted pyrolysis (MAP) has been perceived as a promising technology for biomass and waste conversion due to its distinctive features, including fast, even, and precise heating. This results in higher energy efficiency when compared to conventional pyrolysis via thermal heating. However, the scaling up of MAP of biomass and waste poses challenges, with investigations ongoing to uncover not only the technological aspect, but also both the environmental impacts and economic feasibility associated with this process/technology. The possible environmental impacts associated with MAP processes can be analyzed through systematic life-cycle assessment (LCA), while the economic feasibility can be evaluated via techno-economic analysis (TEA). This paper presents an overview of the current research trend in MAP and the products produced, as well as the LCA and TEA of the pyrolysis technologies. The LCA study reported a 2.5 folds reduction in energy consumption and up to 62% reduction in global warming potential. TEA study revealed that conventional pyrolysis has a greater profit for long-term assessment due to a higher maturity and less complexity technology; however, MAP may be more economically feasible in the future owing to the increased maturity and more established technology. Finally, the challenges and future perspectives for LCA and TEA in MAP are elucidated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biodegradable polymer-based membranes were processed and tested as microfluidic substrates. • Tailorable morphology, capillary flow, good mechanical properties, biocompatibility. • Quick degradation after their use, over 90 % after 6 weeks. • Confirmed applicability through wax-printed substrates for glucose quantification. • Breakthrough regarding sustainability and compatibility with circular economy. Microfluidic paper-based analytical devices (µPADs) have gained substantial attention as portable analytical devices in various (bio)technological fields, for being affordable, user-friendly, portable, energy efficient and for allowing multiplexed analysis. Although significant progress has been achieved, there is still need for improvement in terms of performance and sustainability. In this work, a biodegradable aliphatic polyester poly(D,L-lactide- co -glycolide acid) lactide:glycolide 50:50 (PDLG), is used to produce pore- and fibre-based membranes, as alternative to conventional paper substrates. Two fabrication methods are used, with potential for industrial scale-up. The processed hydrophobic membranes are post-treated with oxygen plasma to turn them hydrophilic, allowing capillary flows. The physicochemical characterization demonstrates the suitability of the plasma-treated PDLG membranes as microfluidic substrates based on their tailorable morphologies and capillary flow rate from 36.2 ± 4.2 to 84.1 ± 5.2 mm·min−1, excellent mechanical properties and biocompatibility. Further, the membranes maintain their properties for at least 6 months when kept in vacuum and degrade quickly after their use (reaching values higher than 90 % after 6 weeks when wet). Finally, portable analytical platforms suitable for the colorimetric quantification of glucose are demonstrated. These results are of great importance for the design and manufacture of a new generation of sustainable portable analytical devices, compatible with circular economy paradigms, and a step forward to cross the challenging academia to industry barrier for their commercialization and widespread adoption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chemical recycling of polyamide 6 can become profitable at the industrial scale. • Alkaline and acidic hydrolysis and alcoholysis are the most promising pathways. • A payback period of less than 5 years is required. • A non-volatile solvent catalyzing the backbiting depolymerization is most promising. • An integrated reaction and separation zone results in the lowest costs. Chemical recycling has increasingly gained attention in order to mitigate environmental pollution and facilitate the transition to a circular economy. Yet only a minor fraction of the polyamide 6 waste is chemically recycled to its monomer ε-caprolactam. The present paper provides a systematic overview of chemical polyamide 6 re-monomerization pathways, an analysis of each pathway's reaction mechanism, a comprehensive simulative techno-economic process comparison of the alcoholysis and neutral, acidic, and alkaline hydrolysis as well as process opportunities for the chemical re-monomerization of polyamide 6. For this, a conceptual process design was carried out using a connected Aspen Plus and Python model. The results indicate that alkaline hydrolysis is the most energy-efficient process due to its simple integration of the reaction and purification section. In contrast, neutral hydrolysis using subcritical water generates by-products, which require energy-intensive separation, leading to the highest total annual costs. Although the conventional pathway using phosphoric acid requires less energy than the alcoholysis using supercritical isopropanol, the expensive hazardous waste treatment and raw material costs make it less economically attractive. Nevertheless, a cash flow analysis shows that both alkaline and acidic hydrolysis, as well as alcoholysis, become profitable within five years at the chosen scale of 12 kilotons of caprolactam per year. The results suggest that a non-volatile solvent or catalyst that catalyzes the chain-end back-biting depolymerization mechanism of polyamide 6 using an integrated reaction and separation zone with straight distillation or stripping of caprolactam would be the most economically and environmentally attractive process for chemical recycling of polyamide 6. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sewage Sludge Derived Biochar (SSDB) has potential in water, soil, air and carbon management. • Utilizing SSDB is gaining impetus due to its rich composition. • SSDB properties vary with residence time, moisture, temperature, etc. • Economic feasibility is a crucial challenge, which limits SSDB production. • Barriers include PTEs, inconsistent quality, lack of protocols, public perception. With the increase in population and wastewater generation, the management of solid by-products, including sewage sludge (SS), has become a challenge. This article reviews various advantages and challenges associated with the use of sewage sludge-derived biochar (SSDB) and its potential for application in environmental improvement toward the attainment of circular economy. SS is a semi-solid mixture of various components, including potentially toxic elements (PTEs), generated as a by-product from wastewater treatment plants. The economic feasibility associated with SS management is a primary challenge for wastewater treatment plants. The utilization of bio-waste after conversion into biochar is gaining impetus considering its application potential in various fields. Biochar is rich in organic matter and nutrients. Its highly porous structure makes it an attractive alternative to traditional waste management methods. The properties of biochar, especially sludge-derived biochar, are greatly affected by various factors such as residence time, moisture content, pyrolysis temperature, heating rate, etc. This paper reviews recent emerging fields of application for SSDB, including water and wastewater treatment, soil amelioration, air pollution control, and carbon sequestration. The barriers of sludge-derived biochar application and possible strategies to overcome them have also been presented. This review article will promote further research, facilitate the advancement required for the sustainable management of SS and promote the circular economy. [ABSTRACT FROM AUTHOR]

[Display omitted] • P recovery has the potential to lessen the pressure on P imports dependency of the EU. • European countries have enacted legislation for promoting P recovery. • Waste streams and eutrophic environments can be promising P recycling resources. • Literature review on engineering approaches for P release and recovery is presented. • Commercial engineering applications for P recovery in the EU are assessed. Phosphorus (P), one of the essential and indispensable elements for the growth of living organisms, is finite and nonrenewable for a multitude of applications. Economic P recycling can contribute to sustainable P management and lessen the pressure on P imports of the EU. Several European countries now have paved the way for establishing P recovery legislation and successively implemented compulsory recycling from P-rich wastes. This paper provided a comprehensive review for analyzing the potential of existing P recycling resources and engineering technologies in terms of their feasibility and applicability in Europe. Potential P-rich flows from the waste streams and eutrophic environments were deeply investigated. Regarding their technical principles, application, and availability, different engineering approaches for P release enhancement and P recovery were also reviewed in a critical manner. Moreover, assessments on engineering applications for P recycling considering economic feasibility and environmental benefits were also presented. Wastewater treatment plants show promising recovery efficiency, whereas industrial processes with sludge ashes as input allow up to 95% recovery of P. Collectively, in Europe, efficient and sustainable management of P has been recognized as a necessary strategy to meet the growing demand for mineral P. [ABSTRACT FROM AUTHOR]

• Three stages of decomposition observed with thermogravimetric analysis. • Kinetic parameters such as E a , k o , and rate determined by AKTS software. • R2 value was determined to be 96.89% for differential iso-conversional method. • E a of 85 – 190.0 kJ mol−1 calculated by this method. • Thermal predictions reported on SD using isothermal heating regime. Anaerobic digestion (AD) has become an effective waste management method in the agri-food sector to dispose of livestock and food wastes. As AD becomes more widely used new challenges emerge, such as the disposal of digestate by-products. Currently, the principal method for handling solid digestate (SD) is direct application to land as an organic fertiliser. However, as the sector grows, this option is less viable due to nutrition loading on the land and increased eutrophication. This paper explores the potential of using SD as a biofuel source. Additionally, the pyrolysis kinetic triplet of residual SD and thermal predictions was reported for the first time using Advanced Kinetics and Technology Solutions (AKTS) thermokinetics software to model and calculate the activation energy (E a) and other kinetic parameters. ASTM-E698, Ozawa-Flynn-Wall and differential iso-conversional (model-free) methods were used and the E a values calculated from each model were 169.8, 75 – 175.0, and 85 – 190.0 kJ mol−1, respectively. The kinetic triplet can be used in the scale-up or designing of reactor systems considering SD as a feedstock. The kinetic prediction of isothermal pyrolysis of SD indicated that a temperature higher than 210 °C is required for onset of decomposition in the sample. Furthermore, SD has the potential to produce an additional ~27.9 MJ per day at a 500 kW standalone on-farm AD plant. This work has highlighted the potential of waste solid digestate as a potential solid biofuel that could add an additional revenue stream to AD plants and make them more sustainable. [ABSTRACT FROM AUTHOR]

• Antibiotics global consumption and their environmental contamination were shown. • The use biochar for antibiotic sorption yields economic and environmental benefits. • Biochar-based materials are effective in removing antibiotics from water solutions. • Trends in the preparation and application of engineered biochar were described. • Mechanisms involved in the binding and removal of antibiotics were discussed. Antibiotic contamination and the spread of antimicrobial resistant bacteria are global environmental issues. Given the growing consumption of antibiotics, it is crucial to reduce their presence in the environment. Adsorption is one of the most efficient methods for removing contaminants from water and wastewater. For this process to be effective, it is of key importance to identify adsorption mechanisms that allow an efficient and selective adsorbent to be chosen. Carbon-based materials (including activated carbon, biochar and black carbon) are typically used for the adsorptive removal of antibiotics. To enhance the efficiency of adsorption of pharmaceuticals, engineered biochars (physically, chemically and biologically modified biochar) and their composites have attracted increasing interests. Biochar-based sorbents can be produced from various feedstocks, including waste products. The use of "green", low cost or sustainable biochar for contaminant sorption yields economic and environmental benefits. Moreover, this is in line with global trends in creating a circular economy and sustainable development. This paper collates the most recent data on the consumption of antibiotics, their related environmental contamination, and their removal using biochar-based materials. Special attention is paid to the newly emerging approaches of biochar modification and biochar composites in relation to the antibiotic removal from water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sustainable disposal platform for food plastic packaging waste (PPW) was developed. • Chemical components and thermal decomposition of PPW were identified. • Due to structural complexity of PPW, pyrolysis produced complicated plastic oil. • Catalytic pyrolysis over Ni/SiO 2 , plastic oils were converted into H 2. • CO 2 promoted catalytic conversion of complex plastic oils into H 2 and CO. In accordance with global economic prosperity, the frequencies of food delivery and takeout orders have been increasing. The pandemic life, specifically arising from COVID-19, rapidly expanded the food delivery service. Thus, the massive generation of disposable plastic food containers has become significant environmental problems. Establishing a sustainable disposal platform for plastic packaging waste (PPW) of food delivery containers has intrigued particular interest. To comprise this grand challenge, a reliable thermal disposable platform has been suggested in this study. From the pyrolysis process, a heterogeneous plastic mixture of PPW was converted into syngas and value-added hydrocarbons (HCs). PPW collected from five different restaurants consisted of polypropylene (36.9 wt%), polyethylene (10.5 wt%), polyethylene terephthalate (18.1 wt%), polystyrene (13.5 wt%), polyvinyl chloride (4.2 wt%), and other composites (16.8 wt%). Due to these compositional complexities, pyrolysis of PPW led to formations of a variety of benzene derivatives and aliphatic HCs. Adapting multi-stage pyrolysis, the different chemicals were converted into industrial chemicals (benzene, toluene, styrene, etc.). To selectively convert HCs into syngas (H 2 and CO), catalytic pyrolysis was adapted using supported Ni catalyst (5 wt% Ni/SiO 2). Over Ni catalyst, H 2 was produced as a main product due to C H bond scission of HCs. When CO 2 was used as a co-reactant, HCs were further transformed to H 2 and CO through the chemical reactions of CO 2 with gas phase HCs. CO 2 -assisted catalytic pyrolysis also retarded catalyst deactivation inhibiting coke deposition on Ni catalyst. [ABSTRACT FROM AUTHOR]