Rice Husk to Produce Both Bio-H2 Via Dark Fermentation and Photocatalytic Hydrochar

In this work, Bio-H2 was produced through a dark fermentation (DF) process from granulated anaerobic sludge (GAS) using rice husk (RH) as substrate, and to reuse the solid residue generated in this step, a hydrochar capable of degrading the dye rhodamine B (RhB) and the herbicide dicamba were produced. The RH was characterized, prepared, and submitted to an acid hydrolysis process and evaluated from the total sugar (TS) content and concentration of inhibitors. The highest recovery of TS was 19.97 g L−1 and the inhibitors concentrations were lower than the limit of quantification of 0.005 g L−1 for furfural and 0.0005 g L−1 for 5-(hydroxymethyl)furfural. The maximum production and yield of Bio-H2 were 5.37 mL g RH−1 and 0.179 ml H2 h−1 g RH−1, respectively, obtained when using the acid hydrolyzate (1