稀水解液循环回用对玉米秸秆水解液中主要化学组分得率的影响

Influence of Dilute Hydrolysate Recycling on the Yield of Main Chemical Components in the Hydrolysate During Autohydrolysis Pretreatment of Corn Stalk

中文关键词:  玉米秸秆  生物炼制  自水解预处理  水解液回用  化学组分富集

Key Words:corn stalk  biorefinery  autohydrolysis pretreatment  hydrolysate recycling  chemical component enrichment

中文摘要:

      为实现对水洗玉米秸秆自水解预处理固相物产生的稀水解液（简称稀水解液）中主要化学组分的高效利用，探讨了自水解预处理工艺条件以及将稀水解液回用于玉米秸秆自水解预处理对水解液中主要化学组分得率的影响。结果表明，在液固比10∶1（V/w）、170 ℃保温40 min条件下，水解液中糖类化合物、甲酸、呋喃化合物及酚类化合物等主要化学组分得率均达到最大值。在此工艺参数基础上添加2%乙酸作为自水解处理过程中的催化剂，可进一步提高糖类、弱酸类及呋喃化合物的得率。将稀水解液循环回用于玉米秸秆的自水解预处理过程7次后，水解液中主要化学组分则分别进一步显著（P < 0.05）提高21.0%（糖）、71.0%（甲酸）、44.6%（乙酸）、80.7%（酚类化合物）、102.1%（糠醛）及98.5%（5-羟甲基糠醛），有效实现了水解液中主要化学组分的富集和增浓。上述研究为玉米秸秆自水解预处理工艺的调整及稀水解液的利用提供理论依据和数据支持。

Abstract:

      To realize the efficient utilization of main chemical components in the hydrolysate during autohydrolysis pretreatment of corn stalks， effects of autohydrolysis pretreatment conditions and recycling the dilute hydrolysate generated during washing the pretreated solid on the yields of main chemical components in the hydrolysate were investigated. The results showed that the yield of main chemical components such as saccharides， weak acids， furans， and phenols in the hydrolysate during autohydrolysis pretreatment reached the maximum under the pretreatment conditions of liquid-solid ratio 10∶1 （V/w） and 170 ℃ for 40 min. Furthermore， the yield of saccharides， weak acids， and furan compounds in the hydrolysate were further enhanced when 2% acetic acid was added as a catalyst during autohydrolysis pretreatment. After the dilute hydrolysate was recycled for 7 times during the autohydrolysis pretreatment of corn stalk， the yields of main chemical components in the hydrolysate were enriched and significantly enhanced （P<0.05） by 21.0% （saccharides）， 71.0% （formic acid）， 44.6% （acetic acid）， 80.7% （phenolic compounds）， 102.1% （furfural）， and 98.5% （5-hydroxymethylfurfural）， respectively. The results provide theoretical basis and data support for the adjustment of autohydrolysis pretreatment process for corn stalks and the utilization of dilute hydrolysate.