Purification method of high-purity tungsten hexacarbonyl

Abstract

The invention discloses a method for purifying high-purity tungsten hexacarbonyl, which comprises the following steps of: dewatering raw materials, namely dewatering tungsten hexacarbonyl in a manner of placing in a vacuum oven; carrying out sublimation in an oxygen-free anhydrous inert atmosphere, sublimating the raw materials by adopting a sublimation column, removing low-boiling-point fractions and high-boiling-point impurities, and collecting middle-section fractions; performing high-vacuum operation on the system, changing the vapor pressure of the system by adopting high vacuum, continuously changing the vacuum degree of the system, and separating low-boiling-point and high-boiling-point impurities; and scraping, and collecting high-purity tungsten hexacarbonyl. According to the present invention, with the purification method, the organic impurities in the tungsten hexacarbonyl can be effectively removed, the inorganic impurities in the tungsten hexacarbonyl can be removed through the ICP-OES full-element detection, the content of all the inorganic impurities is less than 1 ppm, and the purity of the tungsten hexacarbonyl obtained through the purification method is as high as 99.9999%, such that the raw material use requirements of the semiconductor industry can be met.

Description

technical field [0001] The invention relates to a precursor used in the semiconductor industry, in particular to a method for purifying high-purity tungsten hexacarbonyl, and belongs to the technical field of high-purity chemical preparation. Background technique [0002] Tungsten hexacarbonyl is a colorless and toxic white powder, mainly used in the pharmaceutical industry, fine organic synthesis, drug extractant and metal catalyzed reagent. [0003] The method of producing tungsten hexacarbonyl is usually to use newly reduced metal tungsten and carbon monoxide to carry out high-pressure carbonylation reaction, but the content of iron and calcium in the product is relatively high. [0004] Commercially available tungsten hexacarbonyl reagents with good quality have an effective tungsten metal content of about 99%, which contains more silicon, calcium, iron, magnesium and other metal impurities, and contains inorganic water impurities. Such tungsten hexacarbonyl cannot be d...

AI Technical Summary

Problems solved by technology

[0005] The patent documents with patent publication numbers CN102070180 and CN102070180A disclose the synthesis method of industrialized tungsten hexacarbonyl, whose purity can reach 99.9%. The disadvantage is that it is all industrialized production, which is cumbersome, and without better access to vacuum, the purity cannot be reached. to 99.9999%, and inevitably contains moisture

Obviously, it cannot meet the requirements for the use of semiconductor-grade high-purity tungsten hexacarbonyl

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