Detoxification of sisal bagasse hydrolysate using activated carbon produced from the gasification of açaí waste.

Due to its recalcitrance and difficult disruption, biomass requires severe treatment conditions to produce bioproducts. These processes also generate substances that inhibit microbial metabolism, resulting in low conversion of sugars into bioproducts. To minimize this, in this work the sisal bagasse acid hydrolysate was detoxified using the activated carbon obtained from residues of the gasification of açaí endocarp. The adsorbent properties were analyzed, and the effects of experimental parameters related to furfural adsorption were evaluated. Then, the validation of the adsorption experiments was carried out in acid hydrolyzed liquor from sisal bagasse, the fermentation tests being performed with Saccharomyces cerevisiae. Overall, the furfural adsorption in the activated carbon was fast since most of the furfural was removed in the first minutes of the experiment. The Sips isotherm fit the experimental data best, with maximum adsorption capacity of 48.02 mg.g-1. Kinetic data fitted LDF, QDF and FD models, and diffusivity parameters were obtained. After detoxification, the activated carbon from açaí waste removed 52% of furfural, 100% of HMF and 40.4% of acetic acid with moderate loss of sugars (17%). The results confirmed that the adsorbent is effective and promising for removing furfural and other fermentation inhibitors.