Abstract: <SPAN lang=EN-US style="FONT-SIZE: 10.5pt; FONT-FAMILY: " mso-bidi-font-size: 12.0pt; AR-SA; mso-fareast-font-family: 宋体? Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language:>In the preparation of chemical manganese dioxide (CMD),the oxidation of crude manganese dioxide is crucial to increase the tap density of CMD and manganese yield.CMD was prepared by oxiding crude manganese dioxide with sodium chlorate as oxidant.Influences of various process factors on the tap density and yield of product were investigated and the optimum process conditions were obtained</SPAN><SPAN style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: " Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: mso-hansi-font-family: mso-bidi-font-family: ?Times AR-SA?>：</SPAN><SPAN lang=EN-US style="FONT-SIZE: 10.5pt; FONT-FAMILY: " mso-bidi-font-size: 12.0pt; AR-SA; mso-fareast-font-family: 宋体? Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language:>mass concentration of sulfuric acid was 150 g/L,sodium chlorate feeding quantity was 120% of the theoretical value,oxidation reaction time was 3 h,and liquid/solid volume ratio of the reaction system was 3</SPAN><SPAN style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: " Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: mso-hansi-font-family: mso-bidi-font-family: ?Times AR-SA?>∶</SPAN><SPAN lang=EN-US style="FONT-SIZE: 10.5pt; FONT-FAMILY: " mso-bidi-font-size: 12.0pt; AR-SA; mso-fareast-font-family: 宋体? Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language:>1.Under above optimum process conditions,almost all Mn<SUP>2+</SUP> were oxidized into manganese dioxide,and manganese yield reached above 99.8</SPAN><SPAN style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: " Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: mso-hansi-font-family: mso-bidi-font-family: ?Times AR-SA?>％</SPAN><SPAN lang=EN-US style="FONT-SIZE: 10.5pt; FONT-FAMILY: " mso-bidi-font-size: 12.0pt; AR-SA; mso-fareast-font-family: 宋体? Times New Roman?; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language:> and tap density of product was more than 2.0 g/cm<SUP>3</SUP>. </SPAN>