Mechanisms of biohydrogen recovery enhancement from peanut shell by C. guangxiense: Temperature pretreatment ranges from −80 to 100 °C

Abstract

The potential of low-cost bioenergy recovery from peanut shell was limited for its complex cellulose structure. In order to enhance the total reducing sugar (TRS) yield for bio-H2 production, peanut shell with heat (HT, 50–100 °C) or freezing pretreatment (FT, −80 to 0 °C) under different duration (0.5–12 h) was investigated. For uncovering the enhancement mechanisms, morphological feature and crystalline structure were analyzed by scanning electron microscope (SEM) and X-ray powder diffraction (XRD). The optimal pretreatment of 50 °C for 12 h was obtained with TRS yield increased 73.6%, while the H2 yield of 1.25 ml/mg-TRS was peaked with pretreatment at −80 °C. The SEM and XRD further demonstrated that mechanisms of HT and FT were realized through different ways, which were cracking and collapsing in HT, and delamination and peeling in FT, respectively.