The method of controlling the water addition of vpo catalyst auxiliary agent in mah preparation process

Abstract

The invention relates to a method for controlling the addition of water as a VPO catalyst additive in the MAH preparation process, which is characterized in that: the water control valve connected to the shell-and-tube fixed-bed reactor for preparing MAH is connected with an atmospheric humidity instrument and a calculation module , the ambient temperature T and relative humidity RH are measured by the atmospheric temperature and humidity meter, and the measured values ​​are input into the calculation module, and calculated by the formula to accurately control the amount of additive water added. The invention realizes the precise control of the amount of water added to the catalyst bed auxiliary agent, keeps the humidity of the butane mixed gas entering the reactor at a constant value, and is not affected by the temperature and humidity of the environment; improves the high selectivity and yield of the catalyst , the selectivity increased by 2.1%, and the mass yield increased by 2.4%, avoiding: the phosphide is concentrated at the feed end of the reactor due to the low amount of water added, which makes the temperature distribution of the reactor uneven, and excessive water addition causes side effects The occurrence of product increase and so on.

Description

technical field [0001] The invention relates to the field of catalytic oxidation of hydrocarbons with more than 4 carbon atoms, in particular to a method for precisely controlling the addition of catalyst additive water in the process of producing maleic anhydride with n-butane as raw material. Background technique [0002] Maleic anhydride (MAH) is a commonly used basic organic chemical raw material and the second largest acid anhydride raw material in the world after phthalic anhydride, and its downstream products have quite broad development and application prospects. MAH is widely used in synthetic resins, lubricating oil additives, pharmaceuticals, food additives, 1,4-butanediol, γ-butyrolactone, tetrahydrofuran, succinic acid, fumaric acid and a series of important organic chemicals and fine chemicals. [0003] The production of MAH by n-butane oxidation is based on vanadium phosphorus oxygen (VPO) catalyst or VPO catalyst containing a small amount of additives, such a...

AI Technical Summary

Problems solved by technology

This patented technology improves the selectivity and yield of the catalyst by adding trimethyl phosphate and then using water treatment, but it does not explain the controlled addition method and amount of water, and the influence of the humidity of the air itself on the performance of the catalyst

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