以5种煤焦油沥青为原料,喹啉为溶剂,研究了热溶过滤法脱除喹啉不溶物(QI)等杂质的效应,目的是制备QI含量较低的净化沥青。结果表明:热溶过滤法可以有效地脱除喹啉不溶物,QI脱除率随滤网网目增加而提高,但阻力增加,脱除时间变长。综合考虑脱除率和实际可操作性,采用1000目的滤布,QI含量可以降到0.3%以下,基本能达到要求。采用凝胶色谱对QI脱除后沥青的组成和分子量分布的研究表明,热溶过滤脱除了沥青中的大分子组分,分子量减小,分子量分布变窄。
In this paper, the effect of purification of five coal tar pitches for removing Quinoline insolubles was researched by hot filtration to prepare purified pitches. It is demonstrated that QI can be removed effectively by the method, and the efficiency of removing QI is increased with elevated mesh. But the time of filtration is increased due to enhancing resistance. According to the efficiency and maneuverability of removing QL the optimum mesh is 1000,at which QI can be reduced below 0. 3%. The composition and molecular weight distribution of purified pitches were measured by GPC. The results show the big molecules of pitches are separated availably, the molecular weight is decreased, and the molecular weight distributions become narrow.