1）以苯、碳四餾分或正丁烷為原料催化氧化制順酐；
1) Catalytic oxidation of benzene, C4 fraction, or n-butane as raw materials to produce maleic anhydride;
2）從氧化生成的混合氣中回收順酐得到粗酐；
2) Recovering maleic anhydride from the mixture generated by oxidation to obtain crude anhydride;
3）精制粗酐從而獲得順酐產品。
3) Refine crude anhydride to obtain maleic anhydride product.
順酐的技術路線主要分為苯氧化法、碳四烯烴法、苯酐副產法、正丁烷氧化法4種。下面
順酐廠家為您分析：
The Technology roadmap of maleic anhydride production mainly includes benzene oxidation, C4 olefin process, phthalic anhydride by-product process and n-butane oxidation process. The manufacturer of maleic anhydride will analyze for you:
正丁烷氧化制順酐是上近年來發展很快的正丁烷利用途徑，約占順酐總能力的80％。正丁烷法順酐工藝按反應器分為固定床工藝和流化床工藝，其后處理工段所采用的工藝有兩種技術方法，即水吸收法和溶劑吸收法。
The oxidation of n-butane to maleic anhydride is a rapidly developing way of utilizing n-butane internationally in recent years, accounting for approximately 80% of the total production capacity of maleic anhydride. The production process of n-butane maleic anhydride is divided into fixed bed process and fluidized bed process according to the reactor. There are two technical methods used in the subsequent treatment section, namely water absorption method and solvent absorption method.
1.丁烷法固定床工藝：與苯氧化法基本相似，但正丁烷氧化轉化率和選擇性均比苯低，其順酐的摩爾收率按正丁烷計僅為50％~55％，而原料氣體中苯和正丁烷的摩爾濃度基本相同。因此對于同樣規模的裝置，正丁烷法需要較大的反應器和壓縮機。反應溫度400～450℃，壓力為125～130MPa。為了降低正丁烷的單耗，比利時的Pantochim公司采用尾氣循環工藝，吸收塔頂出來的尾氣約50％經處理后與新鮮空氣一并進入反應器。該工藝可使正丁烷的單耗下降約10％。
1. Butane fixed bed process: It is basically similar to the benzene oxidation method, but the conversion and selectivity of n-butane oxidation are lower than benzene. The molar yield of maleic anhydride is only 50%~55% based on n-butane, while the molar concentrations of benzene and n-butane in the raw gas are basically the same. Therefore, for production units of the same scale, the n-butane method requires larger reactors and compressors. The reaction temperature is 400-450 ℃, and the pressure is 125-130MPa. In order to reduce the unit consumption of n-butane, Pantochim Company in Belgium adopts a tail gas circulation process. About 50% of the tail gas from the top of the absorption tower is treated and enters the reactor together with fresh air. This process can reduce the unit consumption of n-butane by about 10%.
2.丁烷法流化床工藝：流化床反應器中，正丁烷和空氣分別進入反應器后混合，避免了其混合時發生爆炸的可能因此原料氣中正丁烷的摩爾分數可以提高到4％，反應所需空氣約為固定床的一半，減少了空氣壓縮機的投資和操作費用。流化床工藝的能耗低于固定床，但丁烷的單耗要比固定床高約8％，另外流化床催化劑的磨損也較大。
2. Butane method fluidized bed process: in the fluidized bed reactor, n-butane and air are mixed after entering the reactor respectively, avoiding the possibility of explosion during mixing. Therefore, the Mole fraction of n-butane in the feed gas can be increased to 4%, and the air required for reaction is about half of the fixed bed, reducing the investment and operating costs of the air compressor. The energy consumption of the fluidized bed process is lower than that of the fixed bed, but the unit consumption of butane is about 8% higher than that of the fixed bed, and the wear of the fluidized bed catalyst is also significant.
3.有機溶劑吸收法工藝：在采用丁烷法順酐的初期，主要是一些苯法裝置通過更換催化劑實現，就是新建的裝置工藝也與苯法基本一致，均為水吸收法回收。由于丁烷氧化反應生成少量的乙酸和丙烯酸，而苯氧化反應幾乎不生成乙酸和丙烯酸，另外丁烷氧化生成的水也比苯氧化多1倍，所以丁烷法水吸收工藝遇到的腐蝕和堵塞問題要比苯法多。
3. Organic solvent absorption process: In the early stages of using the butane method to produce maleic anhydride, some benzene process units were mainly achieved by replacing catalysts, and even the newly built unit process was basically the same as the benzene process, all of which were recovered by water absorption method. Due to the butane oxidation reaction generating a small amount of acetic acid and acrylic acid, while the benzene oxidation reaction hardly generates acetic acid and acrylic acid, and the amount of water generated by butane oxidation is also twice that of benzene oxidation, the butane method water absorption process encounters more corrosion and blockage problems than the benzene method.
In industrial production, the consumption of these two solvents is similar. DIBE solvent treatment requires two processes: water washing and alkali washing, while DBP solvent only requires water washing. In addition, the price of DIBE is higher than that of DBP. For more related matters, come to our website http://www.gddxcpa.com Consult and take a look!
