苯蒸氣與空氣可形成爆破混合物對順酐的分離起主導(dǎo)作用，因此進入反應(yīng)器的混合氣體中苯的濃度應(yīng)在爆破極限之外，一般為1%～1.4%。
Benzene Vapor and air can form a blast mixture that dominates the separation of maleic anhydride, so the concentration of benzene in the mixture entering the reactor should be outside the blast limit, typically 1% to 1.4% .
苯的氧化是強烈的放熱反應(yīng)。 順酐廠家常選擇管式固定床反應(yīng)器，其傳熱面大，管外設(shè)有冷卻系統(tǒng)。 反應(yīng)熱可用于產(chǎn)生高壓蒸汽。
The oxidation of benzene is a strong exothermic reaction. MALEIC anhydride producers often choose tubular fixed bed reactors with large heat transfer surfaces and external cooling systems. The heat of reaction can be used to produce high-pressure steam.
離開反應(yīng)器的氣體含有約1%的順酐，其中約一半的可通過冷卻冷凝成液體，其余可通過吸收回收。吸水或惰性有機溶劑，大多數(shù)工廠選擇水。
The gas leaving the reactor contains about 1% maleic anhydride, of which about half of the MALEIC anhydride can be cooled to a liquid and the rest can be recovered by absorption. Absorbent or inert organic solvent, most plants choose water.
得到的吸收液為濃度為35%～40%的馬來酸水溶液。 它需要用共沸溶劑脫水。
順酐廠家將酸從頭轉(zhuǎn)化為酸酐。 脫水也可以在薄膜蒸發(fā)器中進行。減壓蒸餾可得粗酸酐。
The absorption solution is maleic acid aqueous solution with concentration of 35% ~ 40% . It needs to be dehydrated in AZEOTROPIC solvents. Manufacturers of MALEIC anhydride convert acid from scratch to anhydride. Dehydration can also be done in a thin film evaporator. Crude anhydride can be obtained by vacuum distillation.
