连续带渣浸提法提取天然烟碱

A continuous nicotine extraction process without removing the dregs of tobacco leaves

采用连续带渣浸提法从烟草中获取烟碱 ,通过研究烟碱在溶剂相、水相和烟叶渣之间的分配特征 ,确立了浸提过程的关键控制因素。在控制烟叶初始含水量 30 %～ 50 %、原料超声波处理、调整无机碱添加量为烟叶量的 3%～ 5%等的基础上 ,将烟叶浸泡和液液萃取两步同时进行。确定萃取时间、级数、溶剂比后 ,在日处理 2 0kg烟叶的中试装置进行 4级连续逆流放大实验 ,平均萃取率超过 90 %。整个过程基本无废水排放 ,工艺过程缩短。采用富含正己烷的 6号溶剂油也是本工艺的一大特点 ,萃取效果好 ,毒性低 。

A continuous extraction method has been used in this paper for the extraction of nicotine without removing the dregs of tobacco leaves. Tobacco leaves are first pretreated with alkaline water, and then solvent No.6, which is affluent in hexane, is added into the system. Because the initial moisture content is less than 50%, there is no free water in the process. Since the dregs remain in the extraction system, nicotine is extracted from a film of water on the dregs to the solvent phase at the same time that nicotine is separated from dregs to the water phase. Compared to traditional methods this process has several advantages such as less waste water and time consumption. The amount of alkali, solvent/tobacco leaves ratio, initial moisture content and the extraction temperature are determined in this study. A pilot plant experiment of 20 kg tobacco per day is carried out, the average nicotine extraction rate is above 90%.