前文曾用pH滴定法研究一系列络合剂对锰、铜、铋、氧锆、铍、铬、镁、钻、铅、镓、铊及铝的水解沉淀反应的隐蔽作用,得到各络合剂对每一金属的隐蔽能力顺序。本文报告对镧(Ⅲ)及铈(Ⅲ,Ⅳ)的水解沉淀隐蔽的研究结果。 Britton曾企图利用希土元素水解沉淀的pH不同以分离希土元素,并曾用氢电极 Previously, pH-titration was used to study the covert effect of a series of complexing agents on the hydrolytic precipitation of manganese, copper, bismuth, zirconium, beryllium, chromium, magnesium, diamond, lead, gallium, The order of concealment for each metal. This paper reports the results of the research on the covert precipitation of lanthanum (Ⅲ) and cerium (Ⅲ, Ⅳ). Britton had attempted to use the rare earth elements to hydrolyze the precipitate pH difference to separate the rare earth elements, and had used hydrogen electrode