分子筛及以分子筛为载体的催化剂这类产品中,由于含有硅、铝、铁、锌等复杂的化学组份,干扰钙的络合滴定定量。在现今的分析方法中,对硅的干扰,应用脱水除硅步骤;对锌的干扰,应用沉淀分离,或以氰化物掩蔽。但是分子筛具有高热稳定性,加热脱水,操作繁琐。我们结合多年生产实际,建立了高硅、高铝、铁、锌共存条件下,对硅实现了不分离的快速络合滴定钙的方法,手续简便,结果准确。一应用氟化物掩蔽,消除硅对钙络合滴定的干扰硅对钙的络合滴定干扰,关键在于硅的聚合度。随温度的降低,pH增高,硅的聚合度急速加骤,生成硅酸钙趋向增强,严重阻碍EDTA与钙定量络合。氟化物能使大分子聚合体的偏硅酸转化成单分子氟硅酸,屏蔽硅同钙的络合,从而消除了干扰。我们研究了氟化物对硅解聚的效应,试液的酸度 Molecular sieves and zeolite-based catalysts such products, due to contain silicon, aluminum, iron, zinc and other complex chemical components, interference calcium complexometric titration. In today’s analytical methods, the interference of silicon, the application of dehydration steps of silicon; zinc interference, the use of precipitation separation, or masking with cyanide. However, zeolite with high thermal stability, heat dehydration, cumbersome operation. We combine years of practical production, the establishment of high silicon, aluminum, iron, zinc coexist conditions, the silicon has achieved rapid separation of calcium complex titration method, the procedure is simple and accurate. An application of fluoride masking to eliminate the interference of calcium on calcium complex titration Calcium complexation of silicon titration interference, the key is the degree of polymerization of silicon. With the decrease of temperature, pH increases, the degree of polymerization of silicon increases rapidly, resulting in calcium silicate tends to increase, seriously hindered the EDTA and calcium quantitative complexation. Fluoride can make macromolecular polymer of metasilicate into single-molecule fluorosilicic acid, shielding silicon complex with calcium, thus eliminating the interference. We studied the effect of fluoride on silicon depolymerization and the acidity of the test solution