不同萃取方式对胜利褐煤萃取物结构的影响

The Influence of Different Extraction Methods on Structural Features of Shengli Lignite Extraction

以胜利褐煤为研究对象,选取丙酮、甲醇、四氢呋喃3种溶剂,通过索氏萃取、超声波辅助萃取和微波辅助萃取3种方式萃取胜利褐煤中的小分子物质。通过FT-IR、GC/MS等测试方法对萃取物结构进行了分析。研究表明,3种溶剂的萃取率：四氢呋喃〉丙酮〉甲醇,溶剂本身的性质是主要的影响因素。通过分析萃取物的红外光谱图可知,脂肪烃类物质均以超声波辅助萃取物较多;微波萃取物和索氏萃取物含氧类化合物较多。GC/MS分析结果显示,萃取物主要由脂肪烃、芳烃和含杂原子化合物组成。脂肪烃主要由C10~C24的正构烷烃和少量烯烃以及取代环烷烃构成;芳烃主要为短链取代的苯和萘;含极少量的菲和芘。含杂原子化合物种类丰富,主要为一些长链的烷酸甲酯、醇、酚、醛、酮和含氮化合物。萃取方式不同,萃取物种类也有差异,超声波辅助对于加速脂肪烃类物质的溶出具有显著的效果,索氏萃取和微波辅助对于萃取含杂原子化合物具有明显优势。

Structures of the small molecular compounds of Shengli lignite were studied by solvent extraction method in this paper. Acetone,methanol,THF were used to extract the small molecule compounds of Shengli lignite by soxhlet extraction,ultrasonic-assisted extraction and microwave-assisted extraction. The extracts were analyzed by FT-IR and GC / MS. Research showed that the extraction yields of three solvents by different extraction methods,the result is THF methanol acetone. It indicated the nature of the solvent itself is the main factor in extraction process. The analysis on the extraction of infrared spectrogram showed that aliphatic hydrocarbons are usually from ultrasonic-assisted extraction whereas microwave-assisted and soxhlet extraction contain more oxygen compounds. According to the GC / MS analysis, the extracts are composed of aliphatic hydrocarbons, aromatic hydrocarbons and heteroatom-containing compounds. Aliphatic hydrocarbons mainly include C10~ C24n-alkanes,small amounts of olefins and substituted cycloalkanes. Aromatic hydrocarbons are mainly benzene and naphthalene substituted by short-chains,with very small amount of phenanthrene and pyrene. Heteroatom-Containing compounds are various,containing some long chain alkyl acid methyl ester,alcohol,phenol,aldehyde,ketone and nitrogen compounds. Extracts species vary with extraction methods,ultrasonic-assisted extraction contributes to accelerate the dissolution of aliphatic hydrocarbons,while soxhlet extraction and microwave-assisted extraction have obvious advantages.