Effect of metals on mesophilic anaerobic digestion of strawberry extrudate in batch mode Cubero Cardoso, Juan Serrano Moral, Antonio Waste valorisation Methane production Fractional factorial design Central composite design This research was funded by the Spanish Ministry of Economy, In- dustry, and Competitiveness through the Research Project CTM 2017- 83870-R. Supplementary data to this article can be found online at https://doi. org/10.1016/j.jenvman.2022.116783 According to recent studies, the anaerobic digestion of strawberry extrudate is a promising option with potential in the berry industry biorefinery. However, the lack and/or unbalance of concentrations of metals in some agroindustrial residues could hamper methane production during the anaerobic digestion of these kinds of wastes. In this study, a fractional factorial design was applied to screen the supplementation requirements regarding six metals (Co, Ni, Fe, Cu, Mn, and Zn) for methane production from strawberry extrudate (SE). The logistic model was used to fit the experimental data of methane production-time. It allowed identifying two different stages in the anaerobic process and obtaining the kinetic parameters for each step. Maximum methane production obtained in the first (Bmax) kinetic stage, the methane production in the second stage (P), and the maximum methane production rates (Rmax) concluded a statistically significant effect for Ni and Zn. The second set of experiments was carried out with Ni and Zn through a central composite design to study the concentration effect in the anaerobic digestion process of the strawberry extrudate. The parameters P and Rmax demonstrated a positive interaction between Ni and Zn. Although, Bmax did not prove a statistically significant effect between Ni and Zn. 2023-06-14T07:52:20Z 2023-06-14T07:52:20Z 2023-01-15 info:eu-repo/semantics/article J. Cubero-Cardoso et al. Effect of metals on mesophilic anaerobic digestion of strawberry extrudate in batch mode. Journal of Environmental Management 326 (2023) 116783. [https://doi.org/10.1016/j.jenvman.2022.116783] https://hdl.handle.net/10481/82430 10.1016/j.jenvman.2022.116783 eng http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Atribución 4.0 Internacional Elsevier