초록
Response surface methodology (RSM) with central composite design (CCD) was applied to optimize hydrolysis conditions of water-hyacinth stem (WHS). Firstly, the effects of reaction time (h), % diluted H<SUB>2</SUB>SO<SUB>4</SUB> concentration (v/v) and shaking speed (rpm) for hydrolyze WHS were investigated. The optimum condition for WHS hydrolysis was reaction time of 7.73h, H<SUB>2</SUB>SO<SUB>4</SUB> concentration of 1.31% (v/v) and stirring speed of 264.41rpm in which a maximum total sugar of 13g/L was obtained. Secondly, the hydrolysate WHS obtained from the optimum hydrolysis condition was further used as the substrate for hydrogen production by heat-treated anaerobic sludge. Results showed that the maximum HP of 127. 6 mmol H<SUB>2</SUB>/L was obtained.