Abstract：Ultrafine Co powder with an average particle size below 0.1μm was prepared by hydrogen reduction from the basic Co(OH)2 slurry, which was obtained by mixing the solution of CoSO4 with NaOH. The pH of the slurry was controlled between 8 and 12. The filtration and washing of the slurry were not necessary before hydrogen reduction. The proposed reduction temperature was 170~200oC, concentration of catalyst PdCl2 2 mg/L, partial pressure of H2 was 2~3 MPa, and reduction time about 40 min. Temperature and concentration of PdCl2 showed obvious effects on the reaction, and pH of the end solution showed major effect on particle size of Co powder obtained.
2001, Vol. 1 
