摘要
The separation of the by-product (The volume fraction of 3-picoline is 68.472 2% and 4-picoline 26. 517 6% .) in the synthesis of pyridine by dissociation extraction wasstudied. Six separation conditions of the dissociation extraction-the kind and the dosage ofextractant and organic solvent, the concentration of the extractant and separation temperature-wereinvestigated. Different levels of each factor were chosen to form an orthogonal test of six factorsand five levels. The results show that the volume ratio of 3-picoline and 4-picoline in organicphase is the highest when 24 mL picolines are separated at 0 t by 2. 0 mol/L p-toluenesulfonic andn-heptane whose dosages are 40 mL and 48 mL, respectively. The effect of the separation isconsiderably improved with repetition test. This process of dissociation extraction has commendablepotential for industrial exploitation.
应用解离萃取分离合成吡啶产生的3 -甲基吡啶(3- MPD)与4 -甲基吡啶(4- MPD)的混合物(φ(3- MPD)=68. 472 2%;φ(4- MPD)=26. 517 6% ),对影响解离萃取分离的6个因素萃取剂、萃取剂的浓度及投料量、有机溶剂及投料量,以及分离温度进行了研究.选取了各因素的不同水平进行了六因素五水平的正交试验,以有机相两甲基吡啶的体积比为主要考查对象,筛选出了解离萃取分离甲基吡啶混合物的最佳工艺条件:当甲基吡啶的混合物为24mL时,以浓度为2mol/L的对甲基苯磺酸为萃取剂,用量为40mL,正庚烷为溶剂,用量为48mL,温度为0℃时分离效果最好.通过重复性实验,分离效果得到明显提高,说明此法具有工业化潜力.
