Tianjin University

Yingzhe Yu

Minhua Zhang

He Dong

Hao Gong

Zhongfeng Geng

Xiuqin Dong

Feng Shi

Haoxi Jiang

Shenghua Qian

Minli Tao

Yonghui Li

Huisheng Lv

Fang Meng

Cheng Liu

Sheng Wang

Guochao Yang

There is provided a pretreatment process for a resin catalyst for synthesizing bisphenol A. The pretreatment process includes the following steps: firstly, purging the resin catalyst with gas, to remove residual liquid in the resin catalyst; secondly, allowing the vented resin catalyst to be in contact with a replacement washing solution for static replacement, and removing the replacement washing solution; thirdly, allowing the obtained resin catalyst to be in contact with a replacement washing solution for static replacement; and finally, allowing a leachate to be in contact with the resin catalyst, and removing the leachate, to obtain a pretreated resin catalyst.

Pretreatment process of resin catalyst for synthesizing bisphenol A

The present disclosure relates to a bisphenol A preparation process and device thereof. Each stage of reaction system includes a cooler and reactors, each with four sections, the reactors are filled with bisphenol A synthetic resin catalysts before startup operation, and filling proportions of the catalysts are as follows: ⅓ of the catalysts for the first-section reactor, ⅔ for the second-section reactor, the full amount for the third-section reactor and the full amount for the fourth-section reactor. The three reactors operate in series connection through valves, the reactor with the deactivated catalyst is cut out and the reactor to be used is cut in to maintain the three reactors operating in series every time the system operates ⅓ of the service life of the catalyst, and the process can provide a larger air speed, which is beneficial to eliminating the influence of external diffusion, thereby obtaining higher product benefits.

Bisphenol a preparation process and device thereof

The present disclosure provides a process for reducing by-products in a bisphenol A reaction system. The process includes the following steps: conveying mother liquor produced after reaction, concentration, crystallization and separation of phenol and acetone to a mother liquor recovery system; subjecting the mother liquor obtained from the mother liquor recovery system and a sulfo-containing metal organic framework catalyst to contact for an isomerization reaction; and conveying a product obtained from the isomerization reaction to the mother liquor recovery system, to obtain bisphenol A after crystallization and dephenolization.

Process for reducing by-products in bisphenol A reaction system

The present disclosure relates to a thermal coupling method for preparing ethylene by ethanol dehydration and device thereof. The device includes an ethanol dehydration reaction system, a quenching compression system, an alkaline washing system, a molecular sieve drying system and an ethylene purification and propylene refrigeration cycle system; ethanol dehydration reaction products in the ethanol dehydration reaction system serve as a heat source for preheating, vaporization and superheating of a raw material of ethanol; tower bottoms of an evaporation tower in the quenching compression system serve as a heat source for preheating of a feed stream of the evaporation tower and heating of an overhead gas of a quenching tower; products of ethylene in the alkaline washing system serve as a cold source for cooling of crude ethylene.

Thermal coupling method for preparing ethylene by ethanol dehydration and device thereof

The present disclosure relates to a process and a device for producing vinyl acetate by an ethylene process. By additionally arranging an ethylene recovery membrane assembly in a vinyl acetate synthesis section, the content of inert components such as nitrogen in a circulating system is controlled, ethylene gas is recovered from non-condensable gas, and a recovery rate of the ethylene reaches 58% or above. By adding sideline extraction at a refined VAC tower in a vinyl acetate refining section, a vinyl acetate product with purity higher than 99.98% is obtained, a mass fraction of acetic acid is less than or equal to 20 ppm, a mass fraction of acetaldehyde is less than or equal to 20 ppm, and a mass fraction of water is less than or equal to 100 ppm. In synthesis and refining processes of the vinyl acetate, a cooling method is adopted.

Preparation method of vinyl acetate by ethylene process and device thereof

The present disclosure relates to a method for producing vinyl acetate, comprising a vinyl acetate synthesis process, a vinyl acetate refining process and a separation process of vinyl acetate and ethyl acetate, including an acetic acid evaporator, an oxygen mixer, a vinyl acetate synthesis reactor, a first gas separating tower, a second gas separating tower, a recovered gas compressor, a water washing tower, an absorption tower and a desorption tower, a recycling gas compressor; the vinyl acetate refining process comprising an acetic acid tower, a crude VAC tower, and a fine VAC tower, a rectifying tower, an ethyl acetate tower, a water phase receiving tank, an extracting and rectifying tower and an ethyl acetate phase separator.

Method for producing vinyl acetate

The present invention discloses a method and a device for recovering ethylene during the process for producing vinyl acetate, wherein a double solvent absorption method composed of an absorbent solution and deionized water is adopted. The method is as follows: introducing an outlet stream as an absorbent solution from the upper section of the feeding plate in an acetic acid tower during the rectification stage of vinyl acetate production; delivering same to the top of the lower section of the ethylene recovery tower by a delivery pump; charging refined gas from the tower bottom of the ethylene recovery tower for contacting with the absorbent solution in a counter-current; delivering the absorption bottom solution to the rectification stage for treatment; the gas continuing to rise to the upper section of the ethylene recovery tower and contacting with the deionized water introduced from the top of the tower in a counter-current; absorbing and removing the acetic acid therein; and discharging the residual inert gas, such as N2, from the top of the ethylene recovery tower. The absorbent solution is a mixture of acetic acid, vinyl acetate and water, and comprises by weight percentage of 50-85% acetic acid, 5-30% vinyl acetate and 5-20% water.

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Tianjin, China

Yingzhe Yu