Fig. S.6 Impact of sulphuric, hydrochloric, nitric, and lactic acids in the preparation of a blend

Initial and final fractionation of 1.28 ± 0.27 g of wood bottom ash (WBA) and 3.40 ± 0.20 g of post-harvest vegetable waste digestate (PVWD) before and after blending (at the 96 hours) under 5 acidification conditions: (a) Initial WS extract, (b) final WS extract, (c) initial WI material, and (d) final WI material (n = 3). In this investigation (https://doi.org/10.1016/j.jece.2020.105021), in addition to use a commercial dose for treating the PVWD (0.12 mol H+-H2SO4/kg PVWD, 0.19 mol H+-HCl/kg PVWD, 0.14 mol H+-HNO3/kg PVWD and 0.03 mol H+-CH3CH(OH)COOH/kg PVWD), the WBA was treated by means of severe acidification (6.29 mol H+-H2SO4/kg WBA, 15.21 mol H+-HCl/kg WBA, 11.97 mol H+-HNO3/kg WBA and 0.16 mol H+-CH3CH(OH)COOH/kg WBA). The extracting agents, which were prepared with an acid and ultrapure milli-Q® water, were added to the samples following a ratio of 10 mL for each gram of WBA or PVWD: 10.50 ± 0.22 g and 30.19 ± 0.20 g of extracting agents were added to 1.28 ± 0.15 g of WBA and the 3.40 ± 0.20 g PVWD, respectively.Description