乙醇中痕量苯的测定方法

１前言制备无水乙醇的精馏过程常用苯作为挟带剂Ｉ’］，当乙醇作原料生产酒精饮料、药物制剂或提取物时，仅允许痕量的苯存在，因此需要对乙醇进行苯含量的测定。在苯浓度为ＩＰＰｍ时，用厚度为１厘米的比色皿进行常规的分光光度法测定，仍存在可识别的特征峰，可用于痕量苯的测定。如用常规分光光度分析中的绝对法或用文献［２］介绍的导数光谱法进行测量计算，虽然其表征革浓度的吸光度的相关数值较人，可用于测量苯浓度较低的溶液，但由于仪器精密度及其它干扰因素的影响，实际测定结果会产生较大的偏差，难以得到准确的数据。本文采用…

MEASUREMENT OF TRACE BENZENE IN ETHANOL

As benzene has strong characteristic absorption peak in ultraviolet spectrum region, the spectrophotometry can be applied to determine the trace benzene in ethanol. Comparing with the usual method of determination of absolute peakheight and derivative spectrophotometry, the method of quantitatively analyzing the trace benzene in ethanol by peak-to -background height has the advantage of being able to eliminate systematic and accidental errors and it is testified to be simple, reliable and practicable, According to the experimental results, the relation between pesk-to-backgrund height and concentration of benzene is liner in the range from 1to 100ppm and the fitting equation was given.