水中苯酚和水杨酸的双波长线性回归光度测定法

Spectrophotometric Simultaneous Determination of Phenol and Salicylic Acid with Dualwavelength Linear Regression

目的研究苯酚和水杨酸二组分体系的同时测定方法。方法在六次甲基四胺缓冲溶液中,于269.5nm处,水杨酸有吸收,影响苯酚的测定。经过试验确定以295.5、268.5nm作为苯酚和水杨酸的测量波长,建立了双波长线性回归法测定二组分。按均匀设计法U5(53),配置5组标准混合溶液,测定后给出混合溶液的拟合曲线方程;同时测定了模拟混合样本中的苯酚和水杨酸含量。结果在268.5nm,苯酚和水杨酸溶液分别在0～70μg/ml呈线性关系;在295.5nm,水杨酸在0～70μg/ml也呈线性关系。苯酚和水杨酸在浓度较低时误差较大,而绝大部分分析结果误差均小于2%。结论该测定体系稳定,结果可靠,可用于废水中苯酚和水杨酸的测定。

Objective To explore the spectrophotometric simultaneous determination of phenol and salicylic acid . Methods In the buffer solution of （CH2）6N4,salicylic acid revealed absorption peak at 269.5 nm and interfered with determination of phenol. Two wavelengths for 295.5 nm,268.5 nm were selected as determining wavelength after preliminary test. Dualwavelength linear regression method was established for determination of phenol and salicylic acid. Five groups of mixture standard solutions were prepared as uniform design,the fitting cure equation was given after determining those mixture standard solutions. At the same time,the content of phenol and salicylic acid in five simulation mixture samples were determinationed. Results Linear relationship was observed at concentration of phenol and salicylic acid with 0-70 μg/ml,both at 295.5 and 268.5 nm. The method showed higher relative error at low concentration of phenol and salicylic acid,but not more than 2%. Conclusions The test indicated that the system is stable,the result is reliable. This method can be used for determination of phenol and salicylic acid in the wastewater.