順酐的別離和提純。苯蒸氣和空氣能構成爆破混合物，所以進入反響器的混合氣中，苯的濃度應在爆破極限之外，普通為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%.
苯氧化為強放熱反響，順酐廠家工業上常選用列管式固定床反響器，有很大的傳熱面，管外為冷卻系統，反響熱可用于產生高壓蒸汽。
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.
脫離反響器的氣體中含順酐約1%，用冷卻的辦法可將其間所含一半左右的順酐冷凝為液體，其他局部則用吸收法收回。
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.
吸收劑用水或慵懶有機溶劑，大多數工廠選用的是水。所得到的吸收液是順丁烯二酸的水溶液，濃度35%～40%，需用共沸溶劑停水，
順酐廠家把酸從頭轉化成酸酐。脫水也可在膜式蒸發器中停止。粗酐經減壓精餾可得制品。
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.
