79results about "Tungsten halides" patented technology

An olefin metathesis catalyst and method for producing same is provided.

The invention discloses a method for preparing high-purity tungsten hexafluoride by a fluidized bed, and a device thereof. The method comprises the following steps: leading fluorine gas into a pre-heater and pre-heating to the temperature of 50 to 200 DEG C; allowing the pre-heated gas to enter a fluidized bed reactor, wherein, the temperature inside the fluidized bed is 200 to 400 DEG C, and the pressure is 0.1 to 0.5 MPa; continuously adding metered tungsten powder to the middle part of the reactor; allowing crude tungsten hexafluoride product obtained at the upper part of the reactor to enter a freezing collector, wherein, the freezing temperature is minus 35 to 0 DEG C; vacuumizing the top part of the collector so as to remove non-condensable gas impurity; and liquefying the obtained tungsten hexafluoride solid and allowing the tungsten hexafluoride solid to enter a rectifying tower so as to remove the heavy-component impurity, wherein, the purity of the prepared tungsten hexafluoride gas is as high as above 99.99%. The technique can realize automatic temperature control and automatic material feeding of the reactor; the operation is easy to control, safe and reliable; and filter pipes are internally arranged in the reactor which is equipped with a nitrogen backflow device, thereby preventing the product from carrying the tungsten powder.

The invention relates to a kind of purification method of tungsten hexafluoride gas. First, put impure tungsten hexafluoride gas in the storage tank of crude product into the bottom of absorption column where there are multihole spherical filling of sodium fluoride or potassium fluoride, remove the most impurity of hydrogen fluoride under temperature of 10-80 degree C,put it into rectifying column through pipe and fluidify it, stop entering tungsten hexafluoride gas after fluidifing it for 5kg-50kg, put helium gas of high purity into bottom of tungsten hexafluoride liquid and keep it boiling under temperature between 3 degree C and 20 degree C,the vaporized gas enter rectification column and rises, it gradually gets into condensation and circumfluence during the process of rising ,continues to rectify it to remove impurity, check it with gas chromatography, when concentration of impurity of gas discharged from tower top whose boiling point is higher than that of tungsten hexafluoride gas reduce to the request index, stop entering helium gas of high purity, and when helium gas's index reaches the request, collect tungsten hexafluoride gas of high purity into storage tank of quality product.

The invention provides a preparation method for tungsten hexafluoride gas, relating to fluoride of tungsten. The preparation method comprises the following steps of accessing hydrogen fluoride into an electrolytic bath to prepare fluorine electrolytically; by passing through a purifying purified tower, a first in-depth cooling tank and a second in-depth cooling tank in sequence, purifying the produced low-purity fluorine gas; accessing the purified fluorine gas to a reaction system to perform reaction, generating a crude product, namely tungsten hexafluoride; accessing the purified fluorine gas to a first horizontal fixed fixing bed reactor and a second horizontal fixed fixing bed reactor which are filled with waste tungsten cutting heads to perform reaction; collecting the prepared tungsten hexafluoride gas by a primary condenser, an intermediate condenser and a senior condenser in sequence; respectively unfreezing the collected tungsten hexafluoride gas to flow to a first storage tank, a second storage tank and a third storage tank to collect, discharging the uncondensed or unreacted impurity gas to a spraying tower through a tail part pipeline to perform alkali liquid absorption, heating the crude product tungsten hexafluoride collected by the first storage tank, the second storage tank and the third storage tank, and distilling the heated tungsten hexafluoride to a rectifying tower through a filter to perform rectifying and purifying. By utilizing the waste tungsten cutting heads, the preparation method provided by the invention has the advantages of safe process operation and high purity.

Condensable metal halide materials, such as but not limited to tungsten chloride (WCl₆), can be used deposit films metal or metal containing films in a chemical vapor deposition (CVD) or atomic layer deposition process. Described herein are high purity compositions comprising condensable materials and methods to purify condensable materials. In one aspect, there is provided a composition comprising: tungsten hexachloride which is substantially free of at least one impurity and wherein the tungsten hexachloride comprises at least 90%, preferably 95% and more preferably 99% by weight or greater of a β-WCl₆ and 5% by weight or less of the α-WCl₆ as measured by X-ray diffraction.

A purification method of a tungsten hexafluoride gas relates to a fluoride of tungsten. The purification method comprises the following steps: removing oil by equipment, pressurizing with nitrogen, vacuumizing to the limit, turning on a nitrogen heater, introducing the heated nitrogen into a system, and vacuumizing to the limit; filling a hydrogen fluoride removal tower with nitrogen, putting tungsten hexachloride into the hydrogen fluoride removal tower, introducing high-purity tungsten hexafluoride into a finished product gathering tank, reacting with steam adhered to the wall of the tank to generate hydrogen fluoride, sucking-back impure tungsten hexafluoride in the finished product gathering tank into a rectifying still for low-temperature curing after displacement, detecting content of foreign gas, and stopping high-purity tungsten hexafluoride displacement after qualified; heating primary tungsten hexafluoride and carrying out low-temperature curing, vacuumizing the rectifying still, adsorbing tail gas by a basic spray tower, thawing by hot water, and detecting when pressure is stable and rectifying; carrying out reflux condensation on evaporated tungsten hexafluoride gas in the rectifying tower, removing impurities, rectifying primary tungsten hexafluoride gas and gathering, detecting, gathering by the finished product gathering tank, taking a liquid sample, and detecting metal impurities in tungsten hexafluoride.

The present invention relates to a method for producing delaminated/exfoliated non-ionic inorganic materials, to such materials and their use as additives.

The invention provides a reaction system for preparing tungsten hexafluoride, capable of making the tungsten with specific gravity of 19.25g/cm3 uniformly distributed in the whole reactor, maximizing the contact area of the tungsten and the reaction gas, obviously reducing the volume of the reactor and more easily controlling the reaction heat and obviously improving the reaction efficiency. The invention also provides a method of preparing tungsten hexafluoride by using a fluidized bed reactor through contacting the tungsten with fluorizating agent, comprising the following steps: inputting a tungsten powder into a closed reactor, fluidizing the tungsten powder by injecting pressured inert gas in the reactor and continuously supplying the pressured gaseous fluorizating agent and tungsten powder to make them contact and then react with each other at the fluidized state.

The invention relates to an adsorption tower for preparing high-purity tungsten hexafluoride, and belongs to the technical field of tungsten hexafluoride preparation. The adsorption tower comprises anadsorption tower body, an adsorbent, a feeding mechanism and a discharging mechanism, and can further comprise at least one of a stirring mechanism, a cyclic utilization mechanism and a cleaning mechanism. A baffle net and a filter screen are sequentially arranged in the adsorption tower body from top to bottom; the baffle net is filled with adsorbent particles capable of adsorbing HF; filter screen for filtering granular impurities, the feeding mechanism is used for adding new adsorbent particles into the adsorption tower body; the discharging mechanism is used for discharging adsorbent particles with high utilization rate at the bottom of the adsorbent filled on the baffle net, the stirring mechanism is used for stirring the adsorbent particles filled on the baffle net, the cyclic utilization mechanism is used for desorbing the discharged adsorbent particles for cyclic utilization, and the cleaning mechanism is used for cleaning the filter net. According to the adsorption tower, through reasonable structural design, the utilization rate of an adsorbent can be greatly increased, and the adsorption effect can be improved.

A visible-light-responsive photocatalyst powder includes a tungsten oxide powder. The tungsten oxide powder has color whose a* is −5 or less, b* is −5 or more, and L* is 50 or more when the color of the powder is expressed by an L*a*b* color system. Further, the tungsten oxide powder has a BET specific surface area in a range of 11 to 820 m²/g.

The invention relates to a preparation method of high-purity tungsten hexafluoride, and belongs to the technical field of fluorine chemical industry. The preparation method comprises the following steps: introducing nitrogen trifluoride gas into a cracker containing a catalyst to perform cracking; then enabling a fluorine-nitrogen mixture obtained by cracking to react with tungsten powder; performing condensation to obtain a tungsten hexafluoride crude product; and performing distillation and rectification to obtain tungsten hexafluoride of which the purity reaches 99.999%. The preparation method provided by the invention is safe and economical, the introduction of the catalyst ensures that nitrogen is not needed to be additionally introduced into a feed gas to ensure the safety of reaction, the purity of the obtained product reaches a 6N level, and the subsequent treatment cost is reduced, so that the preparation method is economical and environment-friendly and has great industrial application values.

The invention relates to a tungsten hexafluoride gas purifying device and method and belongs to the field of chemical engineering separation. The device is mainly composed of a rectification kettle, a rectification column and a condenser. Crude product WF6 gas with the purity smaller than or equal to 99% and the HF content being 1-10% is introduced into the rectification kettle, the temperature of the rectification kettle is controlled to be 30-60 DEG C, pressure is controlled to be 0.10-0.40 MPa, the temperature of the condenser is 20-50 DEG C, pressure is 0.05-0.35 MPa, the WF6 liquid is vaporized to rise and liquified to flow back, mass transfer separation happens to WF6 of a gas phase and a liquid phase in the rectification column, and therefore the purpose of removing N2, O2, CO, CO2, CF4, SiF4, SF6, N2O and HF impurities is achieved. The method is simple in technology and low in cost, 99.9999% high-purity WF6 gas can be obtained with gas low in purity and high in HF content as raw materials, and the HF content can be lowered to 0.5*10<-6> or below.

The invention relates to a tungsten hexafluoride purifying device prepared from a bismuth doped low-temperature-resistant material. According to the tungsten hexafluoride purifying device prepared from the bismuth doped low-temperature-resistant material, hydrogen fluoride gas is removed effectively by sodium fluoride adsorption and deep freeze separation, then by combination with a series of purification means such as vacuum removal of light-components, rectification and the like, a large amount of volatile foreign gas and a large quantity of non-volatile metal impurities can be removed, anda tungsten hexafluoride product with purity being 99.999% or higher is produced; by means of the bismuth doped low-temperature-resistant material, the device has good low-temperature-resistant mechanical properties and coefficient of thermal expansion and can work for a long time under repeated ultralow-temperature conditions.

Condensable metal halide materials, such as but not limited to tungsten hexachloride and tungsten pentachloride can be used deposit films metal or metal containing films in a chemical vapor deposition(CVD) or atomic layer deposition process. Described herein are high purity tungsten hexachloride and tungsten pentachloride systems and methods to purify tungsten hexachloride and tungsten pentachloride raw materials. There is provided a purified tungsten hexachloride and tungsten pentachloride containing less than 10 ppm, preferably less than 5 ppm, more preferably less than 1 ppm, and most preferably less than 0.5 ppm of iron and/or molybdenum; and less than 10 ppm, preferably less than 5 ppm of all other trace metals combined including but not limited to aluminum, potassium and sodium.

The invention relates to a method for adsorbing and purifying tungsten hexafluoride.The method comprises the steps of adding fluorinated carbon fibers into a reaction kettle, and conducting on-load operation, so that adsorbent is obtained; adsorbing industrial-grade tungsten hexafluoride with a chromatographic column filled with the adsorbent, so that a tungsten hexafluoride product is obtained.

The purpose of the present invention is to safely synthesize high purity tungsten pentachloride at a higher yield and at a higher purity than in prior art. This method for producing tungsten pentachloride includes: a step of mixing a reducing agent selected from the group consisting of Bi, Hg, Sb, Ti, Al, P, and As with tungsten hexachloride uniformly in an inert atmosphere with a molar ratio of the tungsten hexachloride to the reducing agent being 2.8:1.0 to 3.2:1.0 to obtain a mixture; a step of heating the mixture of the reducing agent and the tungsten hexachloride to 80 to 210° C. at 13 Pa or lower and reducing the same; a step of heating the reduced product of the mixture of the reducing agent and the tungsten hexachloride to 120 to 290° C. at 66 Pa or lower and vacuum distilling the same to remove impurities; and a step of heating the reduced product from which impurities have been removed by the vacuum distillation to 140 to 350° C. at 13 Pa or lower and purifying the same by sublimation to obtain the tungsten pentachloride.

The invention discloses a tungsten hexafluoride synthesis method. The method includes: well mixing tungsten powder with metal fluorides in a reactor; feeding fluorine gas for reactive synthesis of tungsten hexafluoride; after condensation gas-liquid separation of unreacted raw material fluorine gas and product tungsten hexafluoride, returning to the reactor for circular reaction. By reaction of cyclic fluoride gas and tungsten powder in existence of the metal fluorides, reaction efficiency is effectively improved, waste of raw material fluorine gas is reduced, and required volume of the reactor is effectively decreased.