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There is a great global concern about agricultural wastes from food and feed crop processing that have significant environmental impacts. Composting is the most environmentally friendly, cost-effective, and efficient processes that can solve the problems of accumulation and toxicity of agricultural waste. The aim of this study is the detoxification of coffee husk by composting at two temperature conditions ("warm" and "cold"). In the greenhouse, the ambient temperature was changed day by day to mimic the situation of a spring to summer "warm" period (≈16-34 °C) and a spring "cold" period (≈7-20 °C) typical of central Italy. The coffee industry should accept the responsibility for the large amount of organic waste production, which presents toxicity and mass accumulation problems. Coffee husk as the main raw material is not used directly as bio-fertilizer in agriculture sector due to the leaching of phenolic compounds and high pH value. The brewing industry is famous for its mass production, and the brewer residues as a by-product have an extremely acidic pH that makes them an unsuitable material for direct composting, but the mixture of these materials can optimize pH. The addition of cow manure accelerates microbial activity and is a strategy to improve composting rate and maturity. The following mixtures were tested: coffee husk and brewer spent grains in a proportion of 2:1 (Compost 1), coffee husk and cow manure in a proportion of 4:1 (Compost 2), and coffee husk, brewer spent grain, and cow manure in a proportion of 5:3:2 (Compost 3). Quality and maturity of the final composts appeared to be affected by the ambient temperature conditions, which remarkably affected pH, C/N ratio, nutrient and trace elements availability, germination index, microbial biomass carbon, and FDA hydrolysis. Results showed that both sets of temperatures produced composts to be considered standard compost, but "warm" conditions compost showed greater maturity, while the composts produced under "cold" conditions were able to increase seed gemination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Adding photocatalytically active TiO 2 nanoparticles (NPs) to polymeric paints is a feasible route toward self-cleaning coatings. While paint modification by TiO 2 -NPs may improve photoactivity, it may also cause polymer degradation and release of toxic volatile organic compounds. To counterbalance adverse effects, a synthesis method for nonmetal (P, N, and C)-doped TiO 2 -NPs is introduced, based purely on waste valorization. PNC-doped TiO 2 -NP characterization by vibrational and photoelectron spectroscopy, electron microscopy, diffraction, and thermal analysis suggests that TiO 2 -NPs were modified with phosphate (P=O), imine species (R=N-R), and carbon, which also hindered the anatase/rutile phase transformation, even upon 700 °C calcination. When added to water-based paints, PNC-doped TiO 2 -NPs achieved 96% removal of surface-adsorbed pollutants under natural sunlight or UV, paralleled by stability of the paint formulation, as confirmed by micro-Fourier transform infrared (FTIR) surface analysis. The origin of the photoinduced self-cleaning properties was rationalized by three-dimensional (3D) and synchronous photoluminescence spectroscopy, indicating that the dopants led to 7.3 times stronger inhibition of photoinduced e - /h + recombination when compared to a benchmark P25 photocatalyst., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Agro-industrial byproducts and food waste necessitate an environmentally friendly way of reducing issues related to their disposal; it is also necessary to recover as much new raw material from these resources as possible, especially when we consider their potential usage as a precursor for preparing depolluting materials, such as activated carbon. In this work, coffee grounds and olive stones were chosen as precursors and the adsorption capacity of the obtained porous carbons for volatile organic compounds (VOCs) was studied. Microporous activated carbons (ACs) were prepared using chemical (K 2 CO 3 ) and physical (CO 2 ) activation. The influence of the activation process, type, and time of activation was also investigated. Measurements of VOCs adsorption were performed, and methyl-ethyl-ketone (MEK) and toluene were chosen as the model pollutants. The surface areas and total pore volumes of 1487 m 2 /g and 0.53 cm 3 /g and 870 m 2 /g and 0.22 cm 3 /g for coffee ground carbons and olive stone carbons, respectively, were obtained via chemical activation, whereas physical activation yielded values of 716 m 2 /g and 0.184 cm 3 /g and 778 cm 2  g -1 and 0.205 cm 3 /g, respectively. As expected, carbons without activation (biochars) showed the smallest surface area, equal to 331 m 2 /g and 251 m 2 /g, and, hence, the lowest adsorption capacity. The highest adsorption capacity of MEK (3210 mg/g) and toluene (2618 mg/g) was recorded for chemically activated coffee grounds. Additionally, from the CO 2 isotherms recorded at a low pressure (0.03 bar) and 0 °C, the maximum CO 2 adsorption capacity was equal to 253 mg/g., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)