Enzymatic hydrolysis of several pretreated lignocellulosic biomasses: Fractal kinetic modelling

9 Pág.Enzymatic hydrolysis of three pre-treated lignocellulosic biomasses -LCB- (wheat straw-WS-, corn stover-CSV- and cardoon stems -CS-) is studied. These biomasses were pre-treated by two methods: diluted sulfuric acid and acid ethanol-water extraction at six severity levels (H values). Pretreated solid fractions were hydrolyzed with commercial enzyme cocktails at standard conditions. A first-order kinetic fractal model was fitted to the experimental results. This model accurately describes the hydrolysis of all biomasses at all pre-treatment conditions studied. The results show that the formal first-order kinetic constant k depends on the biomass nature. The hydrolysis rate increases as the pre-treatment severity does, while the fractal exponent value h decreases. With these pre-treatments, and in terms of k and h, WS is highly reactive and, at medium H with EW pretreatment, highly accessible; CSV has a low reactivity and high accessibility and CS has the lowest reactivity and an increasing accessibility as severity rises.The authors want to thank Spanish Ministry of Economy and Competitivity (MINECO) for funding this study under Project CTQ2017-84963-C2, and Madrid Regional Government for funding via Project RETOPROSOST P2013-MAE2907, and Chilean National Commission of Scientific and Technological Research (CONICYT) for funding PV post-doctoral grant via a grant “Doctorado Becas Chile/2015” with reference 72160108.Peer reviewe