Weak base pretreatment on coconut coir fibers for ethanol production using a simultaneous saccharification and fermentation process

In this work, coconut coir fibers, which are a good source of lignocellulosic biomass with a composition of 34.80% glucan, 18.30% xylan, 35.80% lignin and 8.70% extractives, were successfully pretreated with ammonium carbonate solution (20 and 25 wt.%) at 80 degrees C for 4, 8 and 12 h working time at laboratory scale. The maximum yield of enzymatic hydrolysis (glucan digestibility) after 8 h was 77.03% and 71.43% after the 20% and 25% ammonium carbonate pretreatment, respectively. The simple simultaneous saccharification and fermentation (SSF) process was anaerobically carried out in order to produce second-generation bioethanol from coconut coir fibers at 37 degrees C. The SSF slurry contained Saccharomyces cerevisiae yeast, 5% w/v glucan (untreated and pretreated samples), and 10 FPU/g glucan of cellulase. Subsequently, the maximum ethanol concentration was 8.65 g/L, after 72 h incubation, from 20% ammonium carbonate pretreated biomass for 8 h.

Automated summary

Coconut coir fibers were pretreated with ammonium carbonate solution, followed by enzymatic hydrolysis to produce glucose, and ultimately bioethanol was produced through simultaneous saccharification and fermentation (SSF). The maximum ethanol concentration was found to be 8.65 g/L after 72 hours of incubation with coconut coir fibers pretreated with 20% ammonium carbonate solution for 8 hours under specific conditions.