Diluted Sulphuric
Acid Hydrolysis of Destarched Sago Fibre assisted with Selected Pre-treatments for
Glucose and Xylose Production
Barji Isfaniza and Awang Adeni Dayang Salwani
Res. J. Chem. Environ.; Vol. 28(1); 13-20;
doi: https://doi.org/10.25303/281rjce13020; (2024)
Abstract
In Sarawak, Malaysia, approximately 7 t of sago fibre waste is produced daily from
a single sago starch processing mill and it is currently disposed of either directly
into a river nearby or in open spaces. On a dry basis, sago fibre contains 58% starch,
23% cellulose, 9.2% hemicellulose and 4% lignin. Our previous study used the trapped
starch of sago fibre as a substrate for producing glucose through an enzymatic hydrolysis
process in which the destarched fibre (DSF) remained unused. This study represents
an attempt to utilise destarched sago fibre (DSF) as a raw material for glucose
and xylose production. The DSF initially underwent a pre-treatment process via dilute
sulphuric acid hydrolysis to liberate xylose for which four parameters were studied:
the solid-to-liquid ratio (5:100-40:100), the dilute sulphuric acid concentration
(0% (v/v) - 9% (v/v)), reaction time (30, 60 and 90 minutes) and the effects of
steaming and microwave pre-treatment.
Steaming pre-treatment led to the highest xylose (28.19 ± 0.78 g/L) and glucose
(78.63 g/L ± 0.22 g/L) production, for which the dilute sulphuric acid concentration
was set at 2% (v/v), reaction time was set at 60 minutes. The solid-to-liquid ratio
was 30:100. Overall, this work indicates that the optimal pre-treatment of DSF can
yield glucose and xylose which can be used to produce bioethanol and xylitol. The
study also suggests that DSF can be an alternative raw material for xylitol production.