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High-purity methanol to be more widely used in medicine, electronics and other fields , but the lower end of high purity methanol , technical route is not yet ripe , not competitive, high-purity methanol is also largely dependent on imports . Industrial methanol refined purification of high purity methanol , methanol, China has rich raw materials , combined with the separation and purification of China in recent years, the rapid development of modern technology , production and preparation of high purity methanol products with high added value , suitable for China's national conditions , has a high research value. Methanol azeotrope can be formed and a variety of organic solvents , so the selection of batch extractive distillation Preparation of high purity methanol . Firstly, the fuzzy comprehensive evaluation method for the choice of solvent comprehensive evaluation of four candidate solvents , water , N, N- dimethyl formamide , dimethyl sulfoxide , monoethanolamine , dimethyl sulfoxide as the final choice batch Extractive Distillation preparation of high purity methanol solvent ; Secondly , the establishment of batch extractive distillation constant molar liquid hold-up model , using a quasi-steady approach to solve the model , added two modes of operation on of solvent added all at once and solvent continuous analog affect the purity of methanol yield a variety of factors, such as the number of theoretical plates , solvent ratio , reflux ratio , etc. , the calculation results show that : the solvent is continuously added , when the feedstock main content of 98%, better than the effect of the solvent was added in one overhead methanol one-pass yield of the product of the average concentration of 99.9% , suitable for the number of theoretical plates of 35 , a solvent ratio of 0.3 , the former fractions of a reflux ratio of 8 , the product segments reflux ratio of 5 , the obtained high-purity methanol up to 60% ; Subsequently, the experimental studies , reflect the purity of the product through the determination of UV transmittance and moisture content , the experimental results to determine the appropriate conditions is consistent with the simulation results , in order to determine the batch extractive distillation preparation of high purity methanol the optimum conditions .
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