METHOD FOR PRODUCING HIGH-PURITY TUNGSTEN POWDER,申请号KR20127006450-传众专利搜索

METHOD FOR PRODUCING HIGH-PURITY TUNGSTEN POWDER

申请公布号：KR20120057627(A)

申请号：KR20127006450

申请日期：2010.09.28

申请公布日期：2012.06.05

申请人：

JAPAN NEW METALS CO., LTD.;JX NIPPON MINING & METALS CORPORATION

发明人：SATO JIN;TAKEMOTO KOUICHI;SASAKI TAKESHI;OHNO MIKIO;OGURA JUNJI

分类号：B22F9/22;B22F1/00;C22C27/04

主分类号：B22F9/22

摘要：[Abstract] Provided is a method for producing a high-purity tungsten powder having a phosphorus content of less than 1 wtppm; wherein an ammonium tungstate solution containing 1 wtppm or more of phosphorus as an impurity in terms of the inclusion in tungsten is used as a starting material, this solution is neutralized with hydrochloric acid at a temperature of 50°C or less to adjust the pH at 4 or more and less than 7 so as to precipitate ammonium paratungstate undecahydrate crystals, the resulting solution is heated to 70 to 90°C and filtered in a high-temperature state so as to obtain ammonium paratungstate pentahydrate crystals, the obtained crystals are calcined so as to form a tungsten oxide, and the tungsten oxide is subject to hydrogen reduction so as to obtain a high-purity tungsten powder. Additionally provided is a method for producing a high-purity tungsten powder having a phosphorus content of 0.4 wtppm or less; wherein the ammonium tungstate solution is neutralized with hydrochloric acid to adjust the pH at 4 or more and 6 or less, and this solution is subject to the same procedure as described above so as to obtain a high-purity tungsten powder. Consequently, the phosphorus content can be efficiently reduced.