偶氮氯膦Ⅰ光度法测定铝已有文献报导,但微量钛和少量铬影响测定。本文在研究偶氮氯膦mN(CPA-mN)与铝显色反应时,发现钢铁中一般常见合金元素,较偶氮氯膦Ⅰ与铝显色反应允许量大,以5g基体铁计算,钛在2％以下,Cr(Ⅲ)4％和Cr(Ⅵ)20％以下不影响测定,适用于合金钢中铝的测定,该法显色迅速,操作简便,可直接测定钢铁中的铝。 一、主要试剂 Determination of aluminum by chlorophosphonazo I photometric method has been reported in the literature, but trace amounts of titanium and a small amount of chromium were measured. In this paper, the study of chlorophosphonazo mN (CPA-mN) and aluminum color reaction, found in steel common alloying elements, compared with chlorophosphonazo I and aluminum color reaction allowable amount of 5g matrix of iron, titanium Under 2%, Cr (Ⅲ) 4% and Cr (Ⅵ) 20% do not affect the determination. It is suitable for the determination of aluminum in alloy steel. The method has the advantages of rapid color development, easy operation and direct determination of aluminum in steel. First, the main reagent