研究了硅钼黄光度法的显色反应 ,考察了碱熔后的浸取液中沉淀对二氧化硅的吸附情况 ,提出用返酸化法溶解碱液中的沉淀 ,并在显色体系中加入丙酮作为稳定剂和增色剂来进行光度法测定。该法消除了沉淀吸附对测定结果的影响 ,应用于冶金炉渣中二氧化硅的测定 ,结果令人满意。 The color reaction of silicon molybdenum yellow luminosity method was studied. The adsorption of silica on the leaching solution after alkali fusion was investigated. The precipitation of alkali solution was proposed by the back acidification method and the addition of Acetone is used as a stabilizer and a color enhancer for photometric determination. The method eliminates the influence of precipitation adsorption on the determination results and is applied to the determination of silica in metallurgical slag with satisfactory results.