在pH 3.0的克拉克-鲁布斯缓冲溶液中,铂(Ⅳ)以PtBr2-6·2CTMAB+的形式从含有0.59 mol·L-1硝酸钠、5.0×10-3mol·L-1溴化钾及3.0×10-3mol·L-1十六烷基三甲基溴化铵(CTMAB)的试液中定量浮选分离.此方法中浮选分离时试液的总体积定为10 mL,其中含0.1 mol·L-1溴化钾溶液0.5 mL,0.01 mol·L-1 CTMAB溶液3 mL及硝酸钠0.5 g.试验结果表明:100 μg铂(Ⅳ)有效地与多达1.0 mg的铬(Ⅲ)、锰(Ⅱ)、铝(Ⅲ)、镍(Ⅱ)、镓(Ⅲ)、铁(Ⅱ)及锌(Ⅱ)分离,铂(Ⅳ)的浮选率达100%.此方法应用于已知含铂0.102%(质量分数)的Ni-Pt/Al2O3催化剂的分析,测得铂量的平均值为0.099%,测定值的相对标准偏差(n=7)为2.2%.

In a clark-Lubs buffer medium of pH 3.0,platinum(Ⅳ) was quantitatively separated by floatation as PtBr2-6·2CTMAB+ from testing solution containing 0.59 mol·L-1 of NaNO3,5.0×10-3mol·L-1 of KBr and 3.0×10-3mol·L-1 of CTMAB. As a total volume of 10 mL was taken in the floatation process,0.5 mL of 0.1 mol·L-1 KBr solution,3 mL of 0.01 mol·L-1 CTMAB solution and 0.5 g of NaNO3 were added. As shown by experimental results 100 μg of Pt(Ⅳ) were effectively separated from as much as 1 000 μg of Cr(Ⅲ),Mn(Ⅱ),Al(Ⅲ),Ni(Ⅱ),Ga(Ⅲ),Fe(Ⅱ) and Zn(Ⅱ),achieving to a floatation rate of about 100%. The proposed method was applied to the analysis of sample of Ni-Pt/Al2O3 catalyst with known Pt content (w) 0.102%. Result of average content of platinum found by this method was (w) 0.099% and value of RSD′s (n=7) calculated from the analytical data was 2.2%.