High-Temperature Dilute-Acid Hydrolysis of Hazelnut Shells for Xylose and Furfural Production

In this study, the effect of dilute acid catalyzed, high temperature pretreatment of hazelnut shells at different temperatures (120, 160, 200°C) and reaction times (0, 10, 30 minute) on the xylose and furfural yield were investigated. Xylose production decreased with increasing temperature from 120 to 200°C, due to conversion of xylose to other substances (especially furfural). Maximum xylose production (12.02 mg/ml) was observed when hazelnut shells were hydrolyzed at 120°C for 10 minutes duration time in 1% sulphuric acid solution. Under these conditions, the contents of furfural, 5-hydroxymethylfurfural, acetic acid and glycerol were found as 0.29 mg/mL, 0.024 mg/mL, 2.21 mg/mL and 0.29 mg/mL respectively. Although, increasing temperature from 120 to 160°C resulted in some positive effects on furfural production, the xylose production was decreased. Furfural production was maximized (2.88 mg/mL) at the 160°C for 30 minutes duration time in 1% sulphuric acid solution.