Effect of amphiphilic lignin derivatives (A-LD) surfactant addition on the fermentation process of sorghum bagasse kraft pulp for bioethanol production

Abstract

This research was intended to study the effect of Amphiphilic Lignin Derivatives (A-LD) surfactant addition on the bioethanol production by using simultaneous saccharification and fermentation (SSF) system. A-LD synthesis was obtained from single-step lignin isolation from black liquor as a by-product of the Acacia mangium kraft process. This synthesis was carried out by reacting single-step lignin isolation with the polyethylene glycoldiglycidylether (PEDGE), which was heated at 60 °C for one h. SSF was performed by using Saccharomyces cerevisiae InaCC Y93, cellulase enzyme of 50 FPU/g, yeast inoculum in 10% and 20%, and a 15 mg/mL A-LD added into 5.37 g (wet weight) of sweet sorghum bagasse (SSB) kraft pulp. The concentration of reducing sugar and the ethanol contents were analyzed every 24 h for 72 h and also at 89 h. The ethanol concentration, ethanol yield, and the highest percentage of theoretical ethanol yield were 4.91 ± 0.10 g/L, 0.06 ± 0.001 g/g, and 11.29 ± 0.22%, respectively. They were obtained by 20% of yeast inoculum for 24 h fermentation on the SSF system and the addition of A-LD surfactant. The addition of A-LD on the SSF process increased ethanol production and shortened the fermentation time.