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为了监测钴钼催化剂浸渍液中高浓度Co(Ⅱ)含量,基于Co(Ⅱ)/KSCN反应体系,建立了一种能测定上述离子的流动注射分光光度系统.研究发现:Co(Ⅱ)与KSCN络合物是由K2 Co (SCN)4和K4Co(SCN)6构成,利用第二种物质可以定量Co(Ⅱ);共浸液实样在碱性或强酸性条件下能形成稳定均一的溶液,而在中性和弱酸性条件下则会出现大量溶质析出的问题.利用硫酸将样品酸化至pH≈0.38,可以实现实样的测定.另外,本研究对相关影响因素进行了优化,得到的测定条件为:显色剂由37.5％(w/V) KSCN和0.1 mol/L NaAc-HAc (pH 5.8)组成,载流为1.0 mol/L硫酸,系统出口总流量为2.0 mL/min,样品定量环体积为90μL,显色剂定量环体积为220 μL,测定波长为620nm.本方法的线性范围5.0 ～ 50.0 g/L,检出限1.3 g/L.系统的RSD＜l.2％ (n=11),回收率为96.0％ ～ 102.7％,分析速度为20样/h.“,”For determinating the content of cobalt in co-impregnating solution of Co-Mo catalysts,based on flow injection spectrophotometry and Co(Ⅱ)/KSCN reaction system,a new automatic analysis system was proposed.This study found that:the reaction product of Co (Ⅱ) and KSCN consisted of K2Co(SCN)4 and K4Co(SCN)6,and the second one could be used to quantify Co(Ⅱ);on alkaline or strongly acidic condition,the sample of co-impregnating solution was stable and homogeneous,but on neutral and weakly acidic conditions,a serious problem of solute precipitation appeared.For solving the problem,the sample was acidized by H2SO4 to pH ≈0.38.The optimized conditions for determination of cobalt were as follows:mixed solution of 37.5％ (w/V) KSCN and 0.1 mol/L NaAc-HAc (pH 5.8)was used as chromogenic reagent;carrier was 1.0 mol/L H2SO4;total flow rate was 2.0 mL/min;the volumes of quantitative loop were 90 μL for samples and 220 μL for chromogenic reagent;detection wavelength was 620 nm.The calibration curve was linear from 5.0 to 50.0 g/L,and the limit of detection was 1.3 g/L.The relative standard deviations (RSD) was less than 1.2 ％ (n =11),the recoveries were in the range of 96.0％ ～ 102.7％,analysis speed was 20 samples per hour.