顺酐的别离和提纯。苯蒸气和空气能构成爆破混合物，所以进入反响器的混合气中，苯的浓度应在爆破极限之外，普通为1%～1.4%。
Separation and purification of maleic anhydride. Benzene vapor and air can constitute a mixture of blasting, so into the mixture of the reverberator, benzene concentration should be beyond the blasting limit, generally 1% ~ 1.4%.
苯氧化为强放热反响，顺酐厂家工业上常选用列管式固定床反响器，有很大的传热面，管外为冷却系统，反响热可用于产生高压蒸汽。
Benzene oxidation is a strong exothermic reaction. In industry, maleic anhydride manufacturers often choose tubular fixed bed reverberator, which has a large heat transfer surface. Outside the tube is a cooling system, and the reaction heat can be used to generate high pressure steam.
脱离反响器的气体中含顺酐约1%，用冷却的办法可将其间所含一半左右的顺酐冷凝为液体，其他局部则用吸收法收回。
About 1% of the maleic anhydride is contained in the gas separated from the resector. About half of the maleic anhydride can be condensed into liquid by cooling, and the other parts can be recovered by absorption.
吸收剂用水或慵懒有机溶剂，大多数工厂选用的是水。所得到的吸收液是顺丁烯二酸的水溶液，浓度35%～40%，需用共沸溶剂停水，
顺酐厂家把酸从头转化成酸酐。脱水也可在膜式蒸发器中停止。粗酐经减压精馏可得制品。
Absorbent water or lazy organic solvents, most factories use water. The resulting absorption solution is an aqueous solution of maleic acid, with a concentration of 35% ~ 40%. Azeotropic solvent is used to stop dehydration and the maleic anhydride manufacturer converts the acid into anhydride from de to de. Dehydration can also be stopped in membrane evaporator. Crude anhydride can be prepared by vacuum distillation.
