Modeling of Pretreatment and Acid/Alkaline Hydrolyses of Lignocellulosic Biomasses in Twin-Screw Extruders

Abstract

A mathematical model for pretreatment and hydrolysis of lignocellulosic biomasses in twin-screw extruders is presented. The model allows for calculation of the concentrations of extracted hemicellulose and sugars (xylose and glucose) at different operating conditions (pressure, temperature, and NaOH and H2SO4 concentrations, as well as screw rotational speed). Parameter sensitivity analyses on the effects of process variables on product concentrations are reported. Regarding the pretreatment case, the effects of NaOH concentration, liquid/solid ratio, and screw rotational speed on the extracted hemicellulose are studied. In the case of hydrolysis, the effects of NaOH concentration, screw rotational speed, and barrel temperature on the final concentrations of glucose and xylose are addressed. Reasonably good agreement between experimental data from different pretreatment/hydrolysis systems and laboratories and the calculations obtained with our model is observed.

Multi-scale reactive extrusion modelling approaches to design polymer synthesis, modification and mechanical recycling

“…controlled degradation or polymerization, can be simulated more accurately. 106 The work of Morales-Huerta et al 109,110 exemplifies the usefulness of hybrid REX models as well. In particular, the authors combined a scheme of 5 reactions and reduced flow equations obtained from simplification of the Navier-Stokes equations to describe the pre-treatment of lignocellulosic biomasses in twin screw extruders.…”

“…Another interesting study is the one of Morales-Huerta et al, 109,110 who applied a similar approach to d'Avray et al 96 In particular, the authors described an extruder as a cascade of CSTRs, considering a detailed reaction scheme. The flow is described based on Navier-Stokes equations, considering for simplicity isothermicity.…”

Modeling of Pretreatment and Combined Alkaline and Enzymatic Hydrolyses of Blue Agave Bagasse in Corotating Twin‐Screw Extruders

“…[ 37–40 ] In previous contributions from our group, we have modeled the pretreatment and alkaline hydrolysis of several biomasses, including BAB, carried out in corotating TSEs. [ 41–43 ]…”

“…In this contribution, we report an experimental and theoretical study on the pretreatment and combined alkaline‐enzymatic hydrolysis of BAB carried out in TSEs. Although we had modeled pretreatment and alkaline hydrolysis earlier, [ 41–43 ] this is the first time that enzymatic hydrolysis is included in our model of what is known as the CES process. The model includes flow equations previously reported by Zagal et al.…”

“…[ 78 ] and in our previous contributions. [ 41–43 ] Our expressions for enzymatic hydrolysis are based on the equations proposed by Kadam et al. [ 62 ] and Al Zuhair et al., [ 79 ] who model the system assuming Langmuir [ 80,81 ] and Michaelis‐Menten [ 81–83 ] approaches for adsorption in heterogeneous systems and enzymatic kinetics, respectively.…”