碱处理对互花米草理化特性的影响研究

研究了5%的NaOH溶液固态处理互花米草后,互花米草的物质结构、物质组成以及水浸提液理化特性的变化.结果表明,经5%的NaOH溶液处理48h后,互花米草的木质纤维结构受到破坏,木质素大分子被碎片化,一些含氮的有机物和碳水化合物受到破坏,导致互花米草水浸提液的COD、TN和有机氮含量大幅增加,分别增加了333.90%、45.26%和25.83倍.对纤维素含量和纤维素结晶度的影响不大,但纤维素的结晶区可能发生了一定的重结晶.半纤维素受到较大程度的破坏,半纤维素含量大幅降低了27.65%,产生了一些羧基类物质.碱处理后,木质素的包裹作用被去除,互花米草的生物降解性能提高.

Effect of alkaline pretreatment on physico-chemical property of Spartina alterniflora

Alkaline pretreatment is widely used of improving biogas production for lignocellulosic materials. This study was conducted to investigate the effect of alkaline pretreatment on physico-chemical property of Spartina alterniflora. Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction patterns, proton nuclear magnetic resonance spectroscopy (1H-NMR), solid-state 13C NMR spectroscopy and some general indicators were used to analyze changes of the lignocellulosic structure and composition of pretreated Spartina alterniflora. The results showed that the lignocellulosic structure of Spartina alterniflora was greatly altered after NaOH pretreatment, resulting in the separation of cellulose from lignin and the decomposition of lignin from large molecules with three-dimensional network structures to small molecules with linear structures. Protein, amino acids and some carbohydrate were also destroyed leading to 333.90% of COD, 45.26% of TN (total nitrogen) and 25.83times of organic nitrogen of water extract of Spartina alterniflora improvement after NaOH pretreatment. However, there were no significant influence on cellulose content and crystallinity of cellulose. Hemicellulose was destroyed obviously with 27.65% reduction, and some carboxyl substances were produced. The results suggested that the lignocellulosic structure was destroyed and the biodegradability of S. alterniflora was increased by alkaline pretreatment.