【作者】 谢英芹；

【导师】 张卫江；

【作者基本信息】 天津大学 ， 化学工程， 2007， 硕士

【摘要】 高纯甲醇在医药、电子等领域得到越来越广泛的应用,但是目前国内的高纯甲醇档次较低,技术路线还不成熟,缺乏竞争力,高纯甲醇在很大程度上还依赖进口。工业甲醇提纯精制高纯甲醇,利用我国拥有的丰富的甲醇原料,结合我国近年来高速发展起来的现代分离提纯技术,生产制备具有高附加值的高纯甲醇产品,适合我国的国情,有很高的研究价值。由于甲醇可以和多种有机溶剂形成共沸,所以本文选用间歇萃取精馏法制备高纯甲醇。本文首先采用模糊综合评判方法进行溶剂的选择,通过对二甲基亚砜、单乙醇胺、水、N,N-二甲基甲酰胺四种候选溶剂进行综合评判,最终选择二甲基亚砜作为间歇萃取精馏制备高纯甲醇的溶剂;其次,建立间歇萃取精馏的恒摩尔持液模型,采用准稳态方法对该模型进行求解,对溶剂一次性加入和溶剂连续加入两种操作方式分别模拟分析了影响高纯甲醇收率的各种因素,如理论板数、溶剂比、回流比等,计算结果表明:溶剂连续加入比溶剂一次性加入效果要好,当原料主含量为98%,塔顶甲醇产品的平均浓度达到99.9%时,适宜理论板数为35块,溶剂比为0.3,前馏分段回流比为8,产品段回流比为5,所得到高纯甲醇的单程收率可达60%;随后,进行了相应的实验研究,通过测定产品的紫外透过率和水分含量反映产品的纯度,实验结果所确定的适宜条件与模拟结果基本一致,从而确定了间歇萃取精馏制备高纯甲醇的最佳工艺条件。更多还原

【Abstract】 High purity methanol has been widely used in the fields of medicament, electronics and so on, and the demand quantity is continuously rising. At present, domestic high purity methanol is low-grade, preparation technology is not yet mature. However, much high purity methanol will also depend on imports. Preparation of high purity methanol with high added value by purifying industrial methanol adapts to the situation of our country and has high research value. It utilizes the abundant raw materials of methanol and the modern purification techniques that have been rapidly developing in recent years. Due to methanol can form azeotropic with a variety of solvents, batch extractive distillation is used for the preparation of high purity methanol in this paper.Firstly, the fuzzy comprehensive evaluation method was used for solvent selection. Several solvents were compared and DMSO was chosen as the separation solvent for the preparation of high purity methanol; Secondly, constant-molar-holdup model of batch extractive distillation was proposed and solved by the quasi-steady approach. The simulation includes two cases: solvent feeding one-off and solvent feeding continuously. Effects of such parametrers as theoretical plates stages, solvent ratio, reflux ratio on recovery fraction of high purity methanol was researched. The simulating results show that the mode that solvent feeding continuously is better than feeding one-off. When the composition of raw material is 98%, and the average purity specification of product in top of column is above 99.9%, the suitable number of theoretical plates is 35, solvent ratio is 0.3, the reflux ratio of slop cut withdrawal and product phase respectively is 8 and 5. Accordingly, the single recovery fraction of high purity methanol can reach 60%. Subsequently, the corresponding experiments were carried out. The purity of product was reflected by values of ultraviolet transmission and content of water. The suitable operating condition that the experimental results educed coincides with the calculated results. Finally, the optimum conditions of the batch extractive distillation for high purity methanol were determined.更多还原