Separation and purification of maleic anhydride from Shandong Province. Benzene vapor and air can form explosive mixture, so the concentration of benzene in the mixture entering the reactor should be beyond the explosion limit, generally 1% - 1.4% (mole). Benzene oxidation is a strong exothermic reaction. Tubular fixed bed reactor is often used in industry. It has a large heat transfer surface and a cooling system outside the tube. The reaction heat can be used to produce high-pressure steam. The gas leaving the reactor contains about 1% (mole) maleic anhydride, about half of which can be condensed into liquid by cooling, and the rest can be recovered by absorption.

吸收劑用水或惰性有機(jī)溶劑，大多數(shù)工廠采用的是水。所得到的吸收液是順丁烯二酸的水溶液，濃度35%～40%(質(zhì)量)，需用共沸溶劑（例如二甲苯、苯甲醚）進(jìn)行脫水，把酸重新轉(zhuǎn)化成酸酐。脫水也可在膜式蒸發(fā)器中進(jìn)行。粗酐經(jīng)減壓精餾可得成品。以苯計(jì)算，整個(gè)過(guò)程的順酐收率為92%～96%（質(zhì)量）。

Absorbent water or inert organic solvents, most plants use water. The absorption solution obtained is an aqueous solution of maleic acid with a concentration of 35% - 40% (mass). Azeotropic solvents (such as xylene and anisole) are used for dehydration to convert the acid into anhydride again. Dehydration can also be carried out in a membrane evaporator. The crude anhydride can be obtained by vacuum distillation. Calculated by benzene, the yield of maleic anhydride in the whole process is 92% ～ 96% (mass).

我公司是一家集、研發(fā)、貿(mào)易為一體的綜合性化工公司。主要涵蓋無(wú)機(jī)化工產(chǎn)品、有機(jī)化工產(chǎn)品、實(shí)驗(yàn)儀器等幾大系列。主營(yíng)產(chǎn)品為氫氧化鉀、過(guò)硫酸銨、過(guò)硫酸鈉、順酐、二氯甲烷、水泥防水劑、色譜儀器毛細(xì)管等六十多個(gè)品種。

Our company is a comprehensive chemical company integrating production, R & D and trade. Mainly covers inorganic chemical products, organic chemical products, experimental instruments and other major series. The main products are potassium hydroxide, ammonium persulfate, sodium persulfate, maleic anhydride, dichloromethane, cement waterproof agent, capillary of chromatographic instrument, etc.