Evaluation of sugar derivatives separation in the liquid hydrolyzate after dilute acid pretreatment using Quercus mongolica

Lignocellulosic biomass, which has been considered as a sustainable and carbon-rich energy source, could be altered into the fuel and chemicals. The production of biochemical is expected to overcome the cost problem of biofuel as a by-product production that is generated during dilute acid pretreatment process. The biochemicals have been recognized as an inhibitor for enzymatic hydrolysis, but can be adopted by the conventional chemical industry and market. Meanwhile, the existing pretreatment of biomass for biofuel production is primarily based on a single-step dilute acid pretreatment process. However, the conversion aspect of biochemical is changed by pretreatment condition such as reaction temperature. Therefore, induction of two-step pretreatment strategy could be achieved for better selectivity of biochemical production than single-step strategy. The first step pretreatment temperatures were designed 140 °C, 150 °C and 160 °C, and then the reaction time was 20 min. 20 g of powder of bark-containing Quercus mongolica was loaded and 1% of aqueous sulfuric acid aqueous solution (w/w) was added at 1/7 (w/v) solid/liquid ratio. The solid residues were applied to enzymatic hydrolysis process. The second step treatment of the liquid hydrolyzate was conducted at same which system of first step pretreatment, but the treatment conditions were changed, the reaction temperature and time were designed within the range of 160-190 °C and 10-30 min, respectively. After the second step treatment, the sugars and derivatives composition in the liquid hydrolyzate were evaluated by HPLC and the derivatives were undergone separation processes.