Abstract The increasing global energy demand, the decline in fossil fuels and the growing amount of municipal solid waste are major environmental and socioeconomic issues, calling for advanced techniques to recycle waste into energy. Here, we review the thermochemical valorization of household, industrial and agricultural waste, with focus on municipal solid waste composition, fuel production, fuel characteristics, legislation and standards. Processes include pyrolysis, gasification, and incineration, e.g. in cement kilns. We found that refuse-derived fuel has a calorific value of 8–20 MJ kg −1 , a moisture content of 8–40% and an ash content of 4–20%. Optimized refused-derived fuel pyrolysis can yield up to 67.9 wt% liquid oil, while gasification produces syngas with heating values up to 10.9 MJ m −3 . In cement kilns, co-processing achieves thermal substitution rates of 50–60% in rotary kilns and 80–100% in calciners. Limitations comprise variability in the composition of the feedstock, tar formation and control of emissions.

Abstract Worldwide pollution of ecosystems by pharmaceuticals is a major health issue requiring the development of advanced, carbon neutral remediation methods. Here we review the use of wood-derived adsorbents, with emphasis on synthesis of wood-derived adsorbents, and their use to remove pharmaceuticals. Adsorbents include sponges, biochar, activated carbon, functionalised wood and wood composites. We detail applications to the removal of antibiotics and non-steroidal anti-inflammatories. Engineered wood sponges achieved adsorption of up to 863.8 mg tetracycline per g, and diclofenac up to 321.3 mg/g, displaying water contact angles of up to 151° due to their higher surface area and improved hydrophobicity. Wood-derived biochar removed up to 397.2 mg/g sulfamethoxazole. Activated carbon removed up to 714.2 mg/g amoxicillin. The higher number of adsorptive sites on functionalised wood enhanced adsorption, showing tetracycline removal up to 305.9 mg/g, and diclofenac removal up 350.0 mg/g. Wood composites have enhanced properties such as a tensile strength of 68.1 megapascals and electrical conductivity of 1858 Siemens/metre for MXene/wood composites. Wood composites showed uptake capacities of up to 106.4 mg/g for diclofenac, and 310.7 mg/g for oxytetracycline hydrochloride.

Abstract Cooking with polytetrafluoroethylene-coated pans releases thousands to millions of microplastic and nanoplastic particles per use, directly contaminating food and the environment. Here we review polytetrafluoroethylene microplastics with emphasis on polytetrafluoroethylene characteristics, environmental occurrence, and detection methods. Polytetrafluoroethylene has high chemical stability and is used in medical devices, clothes and protective suits, aerospace, non-sticking pans, cables and insulation, filtration, irrigation and electronics. We discuss plastic utensils as microplastic sources, and the influence of temperature and aging on microplastic release. The presence of microplastics in humans, wild animals, sediments, water and the atmosphere is described. Limitations of actual analytical methods such as density separation are detailed. Polytetrafluoroethylene accounts for about 60% of the global fluoropolymer market, and is a major contributor to microplastic pollution, accounting for up to 44% of microplastics in sediments, 74% in benthic fish, and 60% in human organs. Our meta-analysis shows that polytetrafluoroethylene microplastic concentrations average 7.3 ± 13.3 particles per L in water, 3,685.7 ± 4,832.0 particles per kg in sediment, 24.9 ± 37.1 particles per individual in fish, and 482.5 ± 554.1 particles per kg in human tissues. Polytetrafluoroethylene microplastics may impair physiological homeostasis by inducing oxidative stress, inflammation, necrosis, and disruption of key cellular signaling pathways.

Abstract Per- and polyfluoroalkyl substances, known as ‘forever pollutants’ due to their very high stability in ecosystems, are industrial contaminants of emerging health concern commonly found in water. Remediation is particularly challenging because existing water and wastewater treatment plants are not designed to remove these pollutants. Here we review methods for the removal of per- and polyfluoroalkyl substances, with focus on the use of cyclodextrins, the cage molecules that can capture smaller substances. We present classical methods and adsorbents such as granular activated carbons, ion exchange resins, advanced oxidation processes, electrochemical degradation, metal–organic frameworks, and membrane filtration. Cyclodextrin-based materials include cross-linked compounds, molecularly imprinted polymers, covalent organic frameworks, and silica hybrids. We describe the complex formed by inclusion of a per- and polyfluoroalkyl substance into a cyclodextrin. We compare the use of cyclodextrins with other removal methods. Cyclodextrins are cyclic oligosaccharides used to prepare polyfunctional materials by cross-linking, immobilization, coating, or self-assembly. Cyclodextrins-based materials are much more efficient for the remediation of per- and polyfluoroalkyl substances, because these cage molecules can be designed to recognize specifically pollutants. As a consequence, cyclodextrins-based materials display much higher adsorption coefficients, in the range of 104—106 L per Kg, compared to less than 104 L per Kg for activated carbon.