预处理温度对玉米秸秆暗发酵制氢性能的影响

为了比较不同预处理温度对玉米秸秆暗发酵制氢性能的影响，在不同温度（40、80、120、160 ℃和200 ℃）下，采用1% H₂SO₄和2% NaOH两种试剂分别对玉米秸秆进行预处理，再进行中温暗发酵实验，接种物来源于以猪粪为原料的厌氧消化后的沼液。结果表明：最佳的预处理条件为80 ℃下，采用1% H₂SO₄对玉米秸秆预处理60 min，其单位总固体（TS）产氢量达到27 mL/g，比未预处理玉米秸秆提高了56.27%，且最大产氢速率最高可达到15.42 mL/h，比未预处理玉米秸秆的最大产氢速率提高了83.57%。玉米秸秆产氢最适宜的pH值范围为5.0~5.5，不同预处理温度会对产酸量和产酸的组分造成影响，发酵类型均为丁酸型发酵。因此，预处理温度是影响暗发酵制氢性能的一个重要因素。

Effect of pretreatment temperatures on the hydrogen production performance in dark fermentation of corn stover

Hydrogen production in dark fermentation has been investigated using corn stover pretreated under different conditions. Two different reagents (1% H₂SO₄ and 2% NaOH) and different temperatures (40, 80, 120, 160 ℃, and 200 ℃) were used in the pretreatment of the corn stover. Dark fermentation experiments were carried out at mesophilic ((37±1) ℃) temperature, and the inoculum was the liquid fraction of digestate from an anaerobic digester composed of a continuously stirred tank reactor with pig manure as the raw material. The results showed that the optimal pretreatment used 1% H₂SO₄ at 80 ℃ for 60 min. The maximum hydrogen production and the maximum hydrogen production rate reached 27 mL/g (total solid, TS) and 15 mL/h, values which are 56% and 84% higher than the corresponding values for untreated corn stover, respectively. The optimum pH range for hydrogen production was found to be from 5.0 to 5.5. The fermentation types were all butyric type. Since the pretreatment temperatures can affect acid production and product composition, it is an important factor affecting hydrogen production in dark fermentation.