研究了利用微晶萘萃取分离痕量Tl(Ⅲ)的新方法。结果表明,在磷酸介质中,3.0g柠檬酸三钠存在下,当50μg/mL KBr溶液用量为1.0mL,1.0×10-3 mol/L罗丹明B溶液用量为1.4mL,1.0×10-2 mol/L萘丙酮溶液用量为3.0mL时,Tl(Ⅲ)与Br-形成的TlBr-4可与罗丹明B发生反应,从而被微晶萘定量吸附。在此条件下Al(Ⅲ)、Cu(Ⅱ)、Zn(Ⅱ)、Ni(Ⅱ)、Mn(Ⅱ)、Mg(Ⅱ)、Hg(Ⅱ)、Cr(Ⅲ)、Bi(Ⅲ)等不被吸附,据此建立了分离富集Tl(Ⅲ)的新方法。对合成水样中铊进行分离和测定,效果良好。
A new extraction separation method of trace thallium(Ⅲ) by microcrystalline naphthalene was studied. The results showed that, in phosphoric acid medium and in presence of 3.0 g of trisodium citrate, when 1.0 mL of 50 μg/mL KBr solution,1.4 mL of 1.0×10-3 mol/L rhodamine B solution and 3.0 mL of 1.0× 10-2 mol/L microcrystalline naphthalene propanol solution were selected, the T1Br4 formed from thallium(Ⅲ) and Br could react with rhodamine B to form complex, which was quantitatively adsorbed by mierocrystalline naphthalene. Under the experimental conditions, other elements such as AI(Ⅲ), Cu(Ⅱ), Zn(Ⅱ), Ni(Ⅱ), Mn(Ⅱ), Mg(Ⅱ), Hg(Ⅱ), Cr(Ⅲ) and Bi(Ⅲ) were not adsorbed. Based on this, a new separation and enrichment method of thallium(Ill) was established. The proposed method was applied to the separation and determination of thallium in synthetic water samples, and the results were satisfactory.