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从木质素磺酸盐氧化和水解转化后的产物——木质素腐植酸盐中分离出腐植酸组分,并用化学和光谱学(UV/VIS,FT-IR,~(13)C-NMR光谱学)的方法对其组成和结构进行表征。同时,从褐煤和山地云杉林森林土有机层中分离出腐植酸,以作为对照。与其它来源的腐植酸相比,木质素腐植酸(LHHA)羧基含量相对较低,而其酸性在一定程度上是通过磺酸基所体现出来的。木质素及其相应腐殖质的~(13)C-NMR光谱在55.9 ppm处有明显的位移,这是其甲氧基碳的信号,而其它烷氧基碳的数量非常有限,如脂肪碳。由于这些类型的碳含量相对较低,木质素腐植酸的芳香度较高,为60.6%。相比天然的腐植酸,木质素磺酸盐经热处理后所得的木质素腐植酸盐则被认为是一种工业化生产的天然腐植物质的类似物。根据化学和光谱学数据评估结果,阐明了从木质素腐植酸盐提取的腐植酸的结构特征,且提出了其可能的化学结构,从而描述了分离组分的典型“平均”特征。
The humic acid component was isolated from the lignin humic acid salt, which is the product of oxidation and hydrolysis of lignin sulfonate and was characterized by chemical and spectroscopic methods (UV / VIS, FT-IR, ~ (13) C-NMR Learn) method of its composition and structure of the characterization. At the same time, humic acid was isolated from the organic layers of the brown coal and the mountain spruce forest as a control. Compared with other sources of humic acid, lignin humic acid (LHHA) carboxyl content is relatively low, and its acidity is to some extent through the sulfonic acid group embodied. The ~ (13) C-NMR spectrum of lignin and its corresponding humus shows a clear shift at 55.9 ppm, which is a signal for its methoxy carbon, while the amount of other alkoxy carbons is very limited, such as aliphatic carbon. Due to the relatively low carbon content of these types, the aroma of lignin-humic acid is high at 60.6%. Compared with natural humic acid, lignin sulfonate obtained after heat treatment of the lignin humic acid salt is considered to be an industrial production of natural humic substances analogues. Based on the results of chemical and spectroscopic data assessments, the structural characteristics of humic acid extracted from lignin humic acid salts are elucidated and their possible chemical structures are proposed, thereby describing the typical “average” character of the separated components.