中文摘要：

在pH 5.66醋酸-醋酸盐缓冲溶液中,Al（Ⅲ）和间磺酸基偶氮氯膦（MSCPA）发生灵敏配位反应。为使Al（Ⅲ）完全反应而过量加入的MSCPA会影响Al-MSCPA配合物吸光值的准确测定。传统光度法无法解决这个问题。在本工作中,光谱修正技术的应用消除了上述干扰,在此537和618 nm被选定为工作波长。结果表明,络合物组成比为Al∶MSCPA=1∶1。新近建立的光吸收比差法（LARVA）被用于测定痕量Al（Ⅲ）,灵敏度可比传统光度法提高10倍以上。Al在0-0.150μg.mL^-1范围内光吸收比差值ΔAr与Al（Ⅲ）浓度成正比,Al（Ⅲ）的检测限仅2μg·L^-1。多种金属离子对测定无干扰,Fe（Ⅲ）和Cr（Ⅲ）的干扰可加入硫脲溶液进行掩蔽。由于配位反应在2 min内即可完成且配合物溶液的吸光度至少能稳定1 h,因此连续流动分析（CFA）被应用,与LARVA组合大大提高了分析效率。结果表明Al（Ⅲ）的检测限为6.5μg·L^-1，每小时大约能分析30个样品。本工作已测定了两种化学试剂中痕量铝,回收率在97.6%-103.5%之间,测定结果满意。

英文摘要：

In a pH 5.66 acetate-acetic acid medium,the complex reaction of Al（Ⅲ） with chlorophosphonazo-mS（MSCPA） is very sensitive.In order to react with Al（Ⅲ） completely,MSCPA must be added excessively enough.Without doubt,the excess MSCPA in the reaction solution affected the measurement of light-absorption of the Al-MSCPA complex.Thus,ordinary spectrophotmetry is unfit for the measurement of such a complex.To eliminate such an interference,both A537 nm and A618 nm were selected as the work wavelengths and the spectral correction technique was applied to the characterization of the above complex.The result showed that the composition ratio of Al（Ⅲ） to MSCPA is 1∶ 1.Using the complexation,a new dual-wavelength approach named the light-absorption ratio variation approach（LARVA） was applied to the determination of trace amounts of Al（Ⅲ）,which often increases the sensitivity up to 10 times better than ordinary spectrophotometry.From the LARVA,the less the MSCPA added,the higher the sensitivity obtained.However,a too low amount of MSCPA caused an obvious error in the measurement because of the noise of instrument background.In the present work,2.80 μmol·L^-1 MSCPA was added into the Al（Ⅲ） solution.The absorbance ratio difference（ΔAr） of the Al-MSCPA solution is proportional to the Al（Ⅲ） concentration in the range of 0 and 0.150 mg·mL^- 1.The LOD of Al（Ⅲ） is only 2 mg·L^- 1.The result indicated that many kinds of metal ions did not affect the direct determination of Al（Ⅲ）.Besides,the addition of thiourea solution may mask Fe（Ⅲ） and Cr（Ⅲ） effectively.The complexation between Al（Ⅲ） and MSCPA was completed in 2 min,and the color absorption of solution remained almost constant for more than 1 h.Therefore,a set of continuous flow analysis（CFA） device was designed for the online rapid analysis of Al（Ⅲ） and coupled with LARVA to increase greatly the analytical efficiency.The results showed that the LOD of Al（Ⅲ） is 6.5 mg·L^-1 and the