一種回收順酐的工藝方法。該方法是以正丁醇與含有順酐生成氣進行酯化反應(yīng)生成單酯，再將單酯分解成正丁醇和順酐。該工藝的特征在于設(shè)置一個熱分解反應(yīng)精餾塔，它以酯化反應(yīng)生成的單酯和一定含量的二酯為原料，在相應(yīng)的工況下在塔內(nèi)進行反應(yīng)蒸餾，塔頂產(chǎn)出正丁醇回酯化反應(yīng)塔循環(huán)使用，塔底產(chǎn)出順酐和二酯去精品精餾塔進行順酐精制。具有吸收快、吸收收率高、不腐蝕設(shè)備、無三廢、、操作可靠特點。
The invention relates to a process for recovering maleic anhydride. In this method, n-butanol is esterified with the gas containing maleic anhydride to produce a monoester, and then the monoester is decomposed into n-butanol and maleic anhydride. The process is characterized in that a thermal decomposition reactive distillation column is set, which takes the monoester and a certain amount of diester generated by esterification reaction as raw materials, carries out reactive distillation in the column under corresponding working conditions, the n-butanol produced at the top of the column is recycled to the esterification reaction column, and the maleic anhydride and diester produced at the bottom of the column are sent to the fine distillation column for maleic anhydride refining. It has the characteristics of fast absorption, high absorption yield, no corrosion of equipment, no three wastes, energy saving and reliable operation.
正丁醇在室溫無催化劑條件下，與含有順酐反應(yīng)生成氣反應(yīng)生成單酯（ＭＢＭ），再將單酯加熱反應(yīng)，生成正丁醇和順酐的工藝路線回收順酐的新工藝，它由酯化反應(yīng)吸收塔１，正丁醇予處理塔２和冷凝器５，冷卻器６，及精品精餾塔４和冷卻器８所構(gòu)成，其特征在于，設(shè)置一個熱分解反應(yīng)精餾塔３及塔頂冷凝器７，該塔以酯化反應(yīng)吸收塔塔底產(chǎn)出的單酯和一定量的二酯為原料。
Under the condition of no catalyst at room temperature, n-butanol reacts with the gas containing maleic anhydride to produce monoester (MBM), and then the monoester is heated and reacted to produce n-butanol and maleic anhydride. It is a new process for recovering maleic anhydride. It is composed of esterification reaction absorber 1, n-butanol pretreatment tower 2, condenser 5, cooler 6, fine distillation tower 4 and cooler 8, The utility model is characterized in that a thermal decomposition reaction distillation tower 3 and a tower top condenser 7 are set, which takes the monoester and a certain amount of diester produced at the bottom of the esterification reaction absorption tower as raw materials.
在進料溫度為５０℃－１２０℃，塔頂真空度為３００－７５０ｍｍＨｇ，回流比為１－３的工況下實行熱分解反應(yīng)精餾，塔頂產(chǎn)出純正丁醇經(jīng)冷凝器７送回酯化反應(yīng)吸收塔１循環(huán)使用，塔底產(chǎn)出順酐與二酯送精品精餾塔４進行順酐精制。
Under the conditions that the feed temperature is 50 ℃ - 120 ℃, the vacuum degree at the top of the tower is 300-750mmhg and the reflux ratio is 1-3, the thermal decomposition reactive distillation is implemented. The pure butanol produced at the top of the tower is sent back to the esterification reaction absorber 1 for recycling through the condenser 7. The maleic anhydride and diester produced at the bottom of the tower are sent to the fine distillation tower 4 for maleic anhydride refining.
