铬铁矿试样经碱熔 ,直接分离铁 ,再酸化 ,中和后用六次甲基四胺沉淀铝与铬分离 ,沉淀酸溶 ,用氟盐取代 -EDTA容量法测定三氧化二铝。该法充分消除了铁的干扰 ,使滴定终点比DZG93-0 12 (铬铁矿操作规程———氟盐酸取代—EDTA容量法测定三氧化二铝 )方法的滴定终点更清晰、准确 ,结果重现性好。 Chromite samples were alkali fusion, direct separation of iron, and then acidified, neutralized with hexamethylenetetramine precipitation of aluminum and chromium separation, precipitation of acid-soluble, with fluoride salt-EDTA method for the determination of aluminum oxide. The method fully eliminates the interference of iron, the titration end point than DZG93-0 12 (chromite operating procedures --- fluorinated hydrochloric acid replacement-EDTA capacity method for the determination of aluminum oxide) titration method endpoint more clearly and accurately, the results of heavy Reality is good.