Assessing the effect of protic ionic liquid pretreatment of Pinus radiata from different perspectives including solvent-water ratio

In this study, pine (Pinus radiata) pretreated with PIL, triethylammonium hydrogen sulfate (TEAHSO(4)) at different water-PIL ratios (1:9, 1:4 and 3:7), biomass loadings (10-60%) and biomass particle sizes (<1.18 mm, 1.18-1.76 mm and 1.76-2.40 mm) was enzymatically transformed into fermentable sugars. TEAHSO(4) removed 52% lignin with pretreatment at 170 degrees C, 20% loading and 1:4 water-PIL ratio for 3 h, from biomass with the largest particle size. Reducing the water content of PIL solution enhanced delignification performance of PIL under the same conditions; cellulose content of the biomass increased 2-fold by extracting 59% lignin from pine. Compositional changes were supported with saccharification and characterization analyses. Utilizing 1:4 water-PIL ratio introduced more constructive pretreatment conditions with respect to the changes in lignin particle size distribution. Attaining favorable compositional changes for pine as a recalcitrant softwood motivated the contribution of PILs to IL based biorefineries.

Automated summary

This study investigated the enzymatic transformation of pine pretreated with TEAHSO(4) at different water-PIL ratios, biomass loadings and biomass particle sizes. Adjusting the water content of the PIL solution enhanced delignification performance and increased cellulose content in the biomass. Utilizing a 1:4 water-PIL ratio introduced more favorable conditions for pretreatment, leading to changes in lignin particle size distribution.