Xi'an Modern Chemistry Research Institute

Xi'an Jiaotong University

Hui Ma

Bo Wang

Wei Zhang

Fengxian Li

Yue Qin

Jian Lv

Wei Mao

Zhenhua Zhang

Chunying Li

Zhijun Hao

Jianhua Wang

Zhiyuan Liu

Yingsan Geng

Sheng Han

Yongmei Du

Jian Lu

Yu Du

Jingyu Shen

Yujie Gu

Liangang Kou

Yanbo Bai

Jijun Zeng

Fei He

Yangbo Ma

Jing Yan

Song Tian

Dianyu Chi

Xiuli Yi

Jing Lv

Zhiqiang Yang

Xiangwen Xiao

Xiaobo Tang

Jianping Kang

Jinyu Shen

Zhaohua Jia

A vacuum degree detection device with buried electrodes in a vacuum interrupter and a method thereof are provided. The vacuum degree wireless detection device includes two parts, wherein a first part is provided inside the vacuum interrupter, including buried electrodes, etc., wherein the buried electrodes are welded on an end cover of the vacuum interrupter; a second part is the external detection device after the arc interrupter is processed, including: detection and calculation components, wireless transmitters, rechargeable energy storage batteries, wireless charging coils, etc. The external detection device and the buried electrode structure is designed separately, and the buried structure such as the buried electrodes can be processed as a whole with the vacuum interrupter. During the detection, the external detection device is installed above the buried electrode structure.

Vacuum degree detection device with buried electrodes in vacuum interrupter and method thereof

A pulse voltage conditioning method of a vacuum interrupter with automatic conditioning energy adjustment based on a trend of a breakdown voltage of the vacuum interrupter during a conditioning process. A current-limiting resistor and a parallel capacitor are automatically adjusted to ensure the conditioning energy reaching a critical value without deconditioning effect. The critical value refers to a maximum conditioning energy without damaging the electrode surfaces, namely an optimal conditioning energy, which can better remove insulation defects on the electrode surface and improve insulation performance of a vacuum gap. The problems of insufficient conditioning and deconditioning effect during conventional voltage conditioning process of the vacuum interrupter can be solved. Therefore, insulation strength of the vacuum interrupter can be raised to a higher level through conditioning.

Pulse voltage conditioning method of vacuum interrupter with automatic conditioning energy adjustment

Disclosed is a catalyst for preparing 2,3,3,3-tetrafluoropropene by gas-phase hydrodechlorination, which solves the problem of the high costs and easy deactivation of traditional chlorofluorocarbon hydrodechlorination catalysts. The disclosed catalyst is characterized in consisting of an active component and a carrier, wherein the active component is a combination of one or more of the metals: Ni, Mo, W, Co, Cr, Cu, Ce, La, Mn and Fe. The catalyst in the present invention has excellent performance, high activity, good stability and a low reaction temperature, effectively reduces reaction energy consumption, and has industrial application value.

Catalyst for preparing 2,3,3,3,-tetrafluoropropene by gas-phase hydrodechlorination

The present application discloses a DC vacuum interrupter. The cup-shaped contact of the vacuum interrupter is in a transverse magnetic field. The magnetic core is placed in the contact cup. The magnetic core inside the cup of the contact works with the permanent magnets outside the vacuum interrupter to generate transverse magnetic fields in multiple directions between the contacts. While the contacts are open, the arc burns and moves rapidly along the ring shaped contacts under the transverse field along the tangent line of the contacts. While the arc moves rapidly along the ring-shaped contacts, the arc column passes the permanent magnets structure and works with the magnetic core to generate multi-polar transverse magnetic field. While the arc column makes a turn, the number of the transverse fields which are cut by the arc is same with the number of the permanent magnets set.

DC vacuum interrupter with multi-polar transverse permanent magnetic structure

Disclosed in the present invention are a chromium-free gas phase fluorination catalyst and an application thereof. The precursor of the related chromium-free gas phase fluorination catalyst consists of a compound containing iron element, a compound containing rare earth metal element and a compound containing element A, wherein element A is one selected from Ca, Al, Mg and Ti, the precursor is subjected to roasting and fluorination treating to obtain the chromium-free gas phase fluorination catalyst. The precursor of the catalyst is roasted at 400-500&#xb0; C. and fluoridized with hydrogen fluoride at 350-450&#xb0; C. to obtain the chromium-free gas phase fluorination catalyst. The catalyst has characteristics of being chromium-free and environment-friendly, good catalytic activity and long life etc. The catalyst can be used for preparing hydrofluoroolefins or hydrochlorofluoroolefins from halohydrocarbons.

Chromium-free catalyst for gas-phase fluorination and application thereof

Disclosed is a process for the preparation of 1,3,3,3-tetrafluoropropene, comprising: (a) a compound having the formula CFClCHClCHFCland in the presence of a compound catalyst, undergoes, through n serially-connected reactors, gas-phase fluorination with hydrogen fluoride, producing 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane; in said formula, x=1, 2 or 3; y=1 or 2, and 3&#x2266;x+y&#x2266;5; (b) 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane undergo, in the presence of a dehalogenation catalyst, gas-phase dehalogenation with hydrogen, producing 3-chloro-1,3,3-trifluoropropene, and 1,1,3,3-tetrafluoropropene; (c) 3-chloro-1,3,3-trifluoropropene and 1,1,3,3-tetrafluoropropene undergo, in the presence of a fluorination catalyst, gas-phase fluorination with hydrogen fluoride, producing 1,3,3,3-tetrafluoropropene. The present invention is primarily used to produce 1,3,3,3-tetrafluoropropene.

Process for the preparation of 1,3,3,3-tetrafluoropropene

A process for the joint preparation of 1,3,3,3-tetrafluoropropene and 2,3,3,3-tetrafluoropropene, comprising: (a) starting materials comprising at least one compound having the structure of formula I, II or III are reacted with hydrogen fluoride, producing 1,2,3-trichloro-3,3-difluoropropene, 1,2,3-trichloro-1,1,2-trifluoropropane, and 1,2,3-trichloro-1,1,3-trifluoropropane; in the compounds of said formulae CFCl&#x2550;CCl&#x2014;CHFCl(Formula I), CFClCHCl&#x2550;CHCl (Formula II), and CFClCFClCHFCl(Formula III), m=0, 1, 2; n=1, 2; p=2, 3; x=1, 2, 3; y=1, 2; z=1, 2 and 4&#x2266;x+y+z&#x2266;6; (b) the 1,2,3-trichloro-3,3-difluoropropene, 1,2,3-trichloro-1,1,2-trifluoropropane and 1,2,3-trichloro-1,1,3-trifluoropropane undergo dechlorination, producing 3-chloro-3,3-difluoropropyne, 3-chloro-2,3,3-trifluoropropene and 3-chloro-1,3,3-trifluoropropene; and (c) the 3-chloro-3,3-difluoropropyne, 3-chloro-2,3,3-trifluoropropene and 3-chloro-1,3,3-trifluoropropene are reacted with hydrogen fluoride, simultaneously yielding 1,3,3,3-tetrafluoropropene and 2,3,3,3-tetrafluoropropen.

Process for the joint preparation of 1, 3, 3, 3-tetrafluoropropene and 2, 3, 3, 3-tetrafluoropropene

Disclosed is a process for the preparation of 2,3,3,3-tetrafluoropropene, comprising the following two reaction steps: a. a compound having the formula CFClCFClCHCl undergoes gas-phase fluorination with hydrogen fluoride through n serially-connected reaction vessels in the presence of a compound catalyst, producing 2,3-dichloro-1,1,1,2-tetrafluoropropane, 1,2,3-trichloro-1,1,2-trifluoropropane, and 1,3-dichloro-1,1,2,2-tetrafluoropropane; in said formula, x=1, 2, 3, y=1, 2, and 3&#x2266;x+y&#x2266;5; b. the 2,3-dichloro-1,1,1,2-tetrafluoropropane, 1,2,3-trichloro-1,1,2-trifluoropropane, and 1,3-dichloro-1,1,2,2-tetrafluoropropane undergo gas-phase dehalogenation with hydrogen in the presence of a dehalogenation catalyst, producing 2,3,3,3-tetrafluoropropene and 3-chloro-2,3,3-trifluoropropene, then separation and refining are performed, producing 2,3,3,3-tetrafluoropropene. The present invention is primarily used to produce 2,3,3,3-tetrafluoropropene.

Process for the preparation of 2, 3, 3, 3-tetrafluoropropene

Disclosed in the present invention is a chromium-free catalyst for gas-phase fluorination and an application thereof. The precursor of the related chromium-free catalyst for gas-phase fluorination consists of a compound containing iron element, a compound containing rare earth metal element and a compound containing element A, wherein element A is one selected from Ca, Al, Mg and Ti, the precursor is subjected to calcination and fluorination treatment to obtain the chromium-free catalyst for gas-phase fluorination. The precursor of the catalyst is calcined at 400-500&#xb0; C. and fluorinated with hydrogen fluoride at 350-450&#xb0; C. to obtain the chromium-free fluorinated catalyst. The catalyst has characteristics of being chromium-free and environment-friendly, good catalytic activity and long life etc. The catalyst can be used for preparing hydrofluoroolefins or hydrochlorofluoroolefins from halohydrocarbons.

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Shaanxi, China

Hui Ma