Methyl tertiary butyl ether crude product purification method

Abstract

The invention belongs to the technical field of chemical engineering, and particularly relates to a methyl tertiary butyl ether crude product purification method. A methyl tertiary butyl ether crude product passes a fixed bed provided with a desulfurization plate to obtain a methyl tertiary butyl ether product with total sulfide content lower than 10mg / kg. A preparation method of the desulfurization plate includes the steps: adding ferric salt, zeolite, attapulgite powder and activated carbon fibers into a high-speed mixer, and mixing the materials to obtain dry powder mixture; adding the drypowder mixture, polyvinyl alcohol and polyacrylamide into water in proportion, uniformly stirring and mixing the materials, pouring mixture into a mold and compacting the mixture; drying a formed blank to obtain the desulfurization plate. The ferric salt, the zeolite, the attapulgite powder and the activated carbon fibers serve as raw materials and are compounded into the desulfurization plate with excellent adsorption and deposition capacity, the methyl tertiary butyl ether crude product is purified, and the sulfide content of the methyl tertiary butyl ether crude product is reduced. The desulfurization plate has high structural strength and has good stability in desulfurization operation.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and in particular relates to a method for purifying crude methyl tert-butyl ether. Background technique [0002] At present, methyl tert-butyl ether (MTBE) is the largest non-hydrocarbon blending component in gasoline in my country, which can significantly improve the quality of gasoline. However, MTBE obviously contains sulfide, which can reach 50-200mg / kg under normal circumstances. , the sulfur content of MTBE produced by some manufacturers is as high as 2000mg / kg. The national standard has more and more strict restrictions on the sulfur content in gasoline. The upper limit of the sulfur content of National III standard gasoline is 150mg / kg, the upper limit of the sulfur content of National IV standard gasoline is 50mg / kg, and the upper limit of the sulfur content of National V standard gasoline The upper limit of sulfur content is 10mg / kg; that is to say, if no active measures are t...

AI Technical Summary

Problems solved by technology

The national standard has more and more strict restrictions on the sulfur content in gasoline. The upper limit of the sulfur content of National III standard gasoline is 150mg / kg, the upper limit of the sulfur content of National IV standard gasoline is 50mg / kg, and the upper limit of the sulfur content of National V standard gasoline The upper limit of sulfur content is 10mg / kg; that is to say, if no active measures are taken, future MTBE will not be able to be transferred into gasoline only because of the problem of sulfur content, which will not only directly affect gasoline production and Supply, also affects the rational utilization of refinery LPG resources

[0003] In the prior art, the method for producing low-sulfur MTBE is usually to re-distill the mixed C4 after the liquefied petroleum gas fractionation, and cut it into light C4 and heavy C4, wherein the isobutylene content in the light C4 is relatively high, and the sulfur content is relatively high. Low, it can be used as a raw material for etherification or alkylation, and the sulfur content of MTBE obtained after etherification is low; the disadvantages of this process include that the energy consumption of distillation and separation of raw materials is high, and the second is due to the sulfuration in heavy C4 The boiling point of the compound is close to that of light C4 such as isobutene, which makes it difficult to separate thoroughly. As a result, the sulfur content of MTBE that can be obtained is difficult to reach below 10mg / kg

[0004] In another idea of ​​obtaining low-sulfur MTBE products, by desulfurizing the prepared high-sulfur MTBE products, low-sulfur MTBE products can also be obtained; for example, a Chinese patent with the application number "CN200910018228. A method for desulfurizing methyl tert-butyl ether with high sulfur content, which discloses the method of re-distillation, re-distilling high-sulfur MTBE, reducing the sulfur content in MTBE by increasing the number of plates and increasing the reflux ratio, The disadvantage of this method is that MTBE needs to be re-distilled. Although the heat of vaporization of MTBE is relatively small, the method of re-distillation can improve the purity of MTBE and reduce the sulfur content, but still requires more plate numbers, and in In the distillation process, a large reflux ratio is required at the top of the tower, which will undoubtedly require more energy consumption, and the investment and maintenance costs of equipment are also high, which is not economically reasonable.

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