Pilot-scale demonstration of SPORL for bioconversion of lodgepole pine to bioethanol and lignosulfonate

Abstract

The process sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL) has been the focus of this study. Pilot-scale (50 kg) pretreatment of wood chips of lodgepole pine ( Pinus contorta Douglas ex Loudon) killed by mountain pine beetle ( Dendroctonus ponderosae Hopkins) were conducted at 165 ° C with a dilute sulfite solution of pH 2 for bioconversion to ethanol and lignosulfonate (LS). The pretreatment duration was optimized in laboratory bench scale experiments with a certain severity based on a combined hydrolysis factor (CHF). The sodium bisulfite loading was 8% and the liquor to wood ratio 3. The pretreated solids were disk milled together with the spent liquid and the resultant slurry with a 25% solids content was directly (without detoxification) submitted to a simultaneous enzymatic saccharification and fermentation (SSF) with Saccharomyces cerevisiae YRH400 at cellulase loading of 35 ml kg -1 of untreated wood. At solids loading of 20%, the alcohol yield was 288 l t -1 wood (with a final concentration of 52.2 g l -1 ), which corresponds to a 72.0% theoretical yield based on total glucan, mannan, and xylan. The LS from SPORL was highly sulfonated and its molecular weight was lower than that of a purified commercial softwood LS, and therefore it has a high potential as a directly marketable co-product.

Efficient Conversion of Lignin to Electricity Using a Novel Direct Biomass Fuel Cell Mediated by Polyoxometalates at Low Temperatures

“…In this work, POM was introduced as am ediatort of acilitate electrona nd proton transfer from lignin to oxygen, resulting in the conversion of lignin to electricity.H owever,m ore investigations on the operating conditions, kinetics, electrode materials, cell design, and assembly have to be done to enhance the powero utput, efficiencya s well as operation stability. [32] and (4) two spent liquors from SPORL pretreatment of al odgepole pine [33] and aD ouglas-fir forest harvest residue, [34] that contained mainly small molecular weight lignosulfonate (Na-LS in the lodgepole pine sample and Ca-LS in the Douglas-fir forest residue) and soluble sugars. The detailed chemical compositions of these lignin samples are listed in Ta ble 3.…”

Direct Saccharification and Fermentation for High Glucose and Ethanol Production from Non‐Detoxified Furfural Residue Without Any Pretreatment

“…From 24 to 72 h, especially from 48 to 72 h, the glucose consumption and ethanol production of FR and WFR‐2 was dramatically increased. According to our previous studies, S. cerevisiae could metabolize furfural and HMF. Thereby, after 24 h metabolization, the effect of inhibitors was reduced.…”

Biorefinery lignosulfonates as a dispersant for coal water slurry

“…The pretreatment conditions for these two feedstocks along with ethanol yields from the subsequent enzymatic saccharification and fermentation of the pretreated whole slurries were listed in Table 4. Detailed descriptions of the two pretreatments and ethanol production can be found in the previously studies [31,32]. After each pretreatment, the woody materials remained intact, therefore, the spent liquor can be easily separately as freely drainable liquid.…”