The tantalum powder produced from the tantalum powder sintered anode and its manufacturing method

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The invention relates to the rare metal smelting field, and particularly, the present invention relates to a tantalum powder for preparing capacitors and a process for preparing the tantalum powder, and to a sintered anode prepared from the tantalum powder. As to the tantalum powder as provided by the invention, its primary tantalum powder has a BET of from 3.0 to 4.5 m2/g. After the secondary agglomeration, the tantalum powder has a large particle size. The tantalum powder has an average Fisher sub-sieve size (FSSS) of 1.2 to 3.0 μm wherein as measured with a standard sieve mesh, more than 75% of tantalum powder has a +325-mesh, and a particle size distribution D50 of more than 60 μm, that is, the secondary particle size is high. A resultant capacitor anode prepared by sintering the tantalum powder of the invention at 1200° C. for 20 minutes and then being energized at the voltage of 20 V has the specific capacitance of from 140, 000 to 180, 000 μFV/g and the residual current of less than 1.0 nA/μFV. Meantime, the invention provides an economical process for making the tantalum powder.