Optimization of Two-Step Acid-Catalyzed Hydrolysis of Oil Palm Empty Fruit Bunch for High Sugar Concentration in Hydrolysate

Table 3

Comparison of total sugar and xylose concentrations in acid hydrolysate with literature results.

Lignocellulose	Acid	Condition	Total sugars (g/L)	Xylose (g/L)	Reference
Rapeseed straw (Brassica napus)	1.76% H2SO4 (w/v)	152.6°C, 21 min, 15 mL liquid/g solid	14	10.5	[11]
Sorghum straw	6% HCl (w/w)	122°C, 70 min, 10 g liquid/g solid	20	16.2	[15]
Silvergrass, rice straw, and bagasse	1–3% H2SO4 (w/w)	121°C, 10–180 min, 10 mL liquid/g solid	27.9/28.1/29.8	24.2/21.9/21.7	[16]
EFB	2% H2SO4 (w/w)	119°C, 60 min, 8 g liquid/g solid	NA*	31.1	[1]
Sugarcane bagasse	3% H2SO4	121°C, 40 min, 4 mL liquid/g solid	NA	57.3	[9]
EFB	3% H2SO4 and 1.2% H3PO4 (w/v)	130°C, 30 min, 3 mL liquid/g solid	83.0	69.5	Step   1; in this study
EFB	Hydrolysate from step   1	130°C, 36 min, 3 mL liquid/g solid	114.4	93.5	Step   2; in this study

∗Not available in the reference.