(406d) Kinetic Modeling of Lime Pretreatment of Switchgrass

Authors: 
Sierra, R., Universidad de los Andes
Falls, M., Texas A&M University


Kinetic models applied to oxygen bleaching of paper pulp focus on the degradation of polymers, either lignin or carbohydrates. Traditionally, they separately model two or three different moieties: (1) a rapid, easy-to-remove polymer, (2) medium, and (2) a slow more-recalcitrant polymer. These models were successfully applied to lignin and carbohydrate degradation of switchgrass submitted to oxidative pretreatment with lime at a wide range of conditions: temperature, total pressure and pretreatment time. The models properly fitted experimental data and were used to determine selectivity of pretreatment in two fashions: differential and integral. Through assessment of selectivity, the detrimental effect of pretreatment on carbohydrates at high temperatures and at low lignin content, amply discussed in literature, was ratified.