AUTHOR=García-Negrón Valerie , Stoklosa Ryan J. , Toht Matthew J. 

TITLE=Effects of NaOH and Na2CO3 pretreatment on the saccharification of sweet sorghum bagasse

JOURNAL=Frontiers in Chemical Engineering

VOLUME=Volume 6 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/chemical-engineering/articles/10.3389/fceng.2024.1449114

DOI=10.3389/fceng.2024.1449114

ISSN=2673-2718

ABSTRACT=In this work, the chemical composition, chemical structures, and sugar release were evaluated for sweet sorghum bagasse (SSB) biomass in response to alkaline pretreatments and enzymatic hydrolysis. Five different ratios of 2 M sodium hydroxide (NaOH) and sodium carbonate (Na 2 CO 3 ) solutions were used for biomass fractionation along with two heat treatment conditions, 85 °C and 150 °C for 1 hour. Sugar yields from enzymatic hydrolysis were measured at different durations up to 72 hours. SSB samples pretreated at high temperature using alkaline solutions containing equal amounts of Na 2 CO 3 and NaOH favored retaining cellulose content (up to 90%) while effectively removing hemicellulose (65%) and lignin (92%). The high-temperature pretreatment conditions resulted in improved delignification, higher sugar concentrations, and sugar yields.Pretreatment solutions consisting of 50% or more NaOH produced higher glucose yields (85-90%) and total sugar concentrations. Moreover, pretreatment solutions containing Na 2 CO 3 improved the hydrolysis rates allowing SSB samples reach maximum yields faster than those without it, 48 versus 72 hours. Results showed pretreatment methods combining NaOH and Na 2 CO 3 were effective at promoting SSB biomass conversion, increasing sugar recovery after hydrolysis, and reducing the hydrolysis duration, all of which are desirable and cost beneficial.