The Impact Of Pretreatment Methods On The Cornstalks Anaerobic Fermentation Hydrogen Production

Hydrogen production through anaerobic fermentation from cornstalk is of great benefit to both environmental improvement and energy recovery. It's a new environmental protection industry which can promote scocial benefit, economical benefit and environmental benefit.In this work, a series of bacth experiments were conducted to enhance biohydrogen production from pretreated cornstalk by using the natural activated sludge was used as inoculum source.Considering the complex constuction and narural nondegradability of cornstalk, ammonia liqour and dilute H2SO4 were applied as reagents to pretreat the substrate. Furthermore, the synergy of high temperature and high pressure (HTHP) and ultrasonic were also systematically studied. The effects of reagants concentration, soaking time, the ratio of liquid to solid, temperature of HTHP, time of HTHP, and ultrasonic time were explored under the fermentative temperature (38℃), initial pH (7.0), and substate concentation (15 g·L-1). The results indicate that the optimal pretreatment for cornstalk was pretreated in 2.0%(w/w) H2SO4 for 1.5 h while the ratio of liquid to solid is 20:1. The maximum hydrogen yield of 142.59 mL·g-1-CS was obtained with an average hydrogen production rate of 17.03 mL·g-1CS·h-1 and hydrogen percentage of 51.49%. The hydrogen yield was 9.3 times higher than the raw cornstalk, and increased by 23.78% than the optimal ammonia pretreatment.This work contrasts the results of various pretreatment methods, and the cornstalk with different pretreatment conditions were analyzed by the SEM which further revealed the H2SO4 (ultasonic) was the best means for cornstalk in promoting the decomposition of cellulose and semicellulose. It coincides with the conclusion of fermentative experiments. Finally, the residual fermentative liqour was collect for composition analysis and the results indicate the primary fermentative mechanism was suggested to be ethanol type.