DPCO—CTMAB分光光度法测定聚烯烃中的钒

本文研究以钒(Ⅴ)一二苯偶氮羰酰肼(DPCO)一溴化十六烷基三甲铵(CT-MAB)为络合体系,分光光度法测定聚烯烃中的钒(V),实验结果表明,以pH值为6.0的醋酸-醋酸钠作为缓冲溶液,络合物的最大吸收峰位于535nm处,钒(V)含量在0-30μg/25mL范围内服从比尔定律,其表观摩尔吸收系数ε_(535)=4.23 × 10~4L/mol/cm相关系数r=0.99998。采用硫脲-盐酸羟胺作为联合掩蔽剂,消除干扰离子的影响。人工合成样的平均回收率为104.12%,RSD为1.60%。聚丙烯、聚乙烯中钒(V)的加标平均回收率分别为101.78%和101.72%,RSD分别为3.74%和2.15%。

Dtermination of vanadium(V)in polyolefine with DPCO-CTMAB by spectrophotometry

In this work,the complex system of V(V )-DPCO-CTMAB was studied and the method of spectro-photometry was used to determine the Vanadium(V) in polyolefine.When the value of pH is 6.0 in the HAc-NaAc buffer solution the maximum absorption wavelength of complex locates at 535nm,Beers law is obeyed when the concentration of Vanadium(V) is between 0 and 30μg/25mL the apparent molar absorption coefficient is ε_(535)=4.23×10~4 L/mol/cm,the correlation coefficient is r=0.99998.In order to eliminate the interference of inter-fering ions,thiocarbamide and hydrochloric hydroxide amic were used for combined screening agents.The recovery rate of the artificial synthetic sample is 104.12%.The relative standard deviation(RSD) is 1.60%.The average recovery rate of Vanadium(V) with the standard addition method in polyethylene and polypropylene is 101.78% and101.72%,the RSD is 3.74% and 2.15%.