摘要
本文研究了阴离子表面活性剂(AS),季铵盐(QAS),磷酞类染料(SPD)显色反应的机理,发现QAS分别与AS和SPD形成离子缔合物,SPD与QAS的摩尔比和SPD的三级电离常数pK,(HL^-)有关,AS和QAS的缔合比为1:1.基于这一显色反应,建立了氯化十六烷基吡啶(CPC)-溴甲酚紫(BCP)光度法测定AS的方法.在60μgCPC存在下,十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)分别在0—55μg·10ml^(-1)和0—50μg·10ml^(-1)范围内符合比耳定律,其表观摩尔吸光系数分别为6.88×104~L·mol^(-1)·cm^(-1)和6.34×10~4L·mol^(-1)·cm^(-1).用建立的方法测定了河水和生活废水中的AS,结果满意.
The mechanism of the chromogenic reaction of anionic surfactants (AS) with quaternary ammonium salts (QAS) and sulphonphthalein dyes (SPD) has been studied. QAS react with SPD and AS to form an ion-associate complex respectively. The molar ratio of AS : QAS is found to be 1 : 1, and the molar ratio of SPD : QAS is found to be correlated with pKa(HL-) of SPD. Based on this chromogenic reaction, a spectrophotometric method has been developed for the determination of AS in water with bromocresol purple (BCP) and cetylpyridinium chloride (CPC). Beer's law is obeyed in the range of 0-55 and 0-50μg·10ml-1 for SDS and SDBS respectively in the presence of 60μg CPC. The apparent molar absorptivities are 6.88×104L·mol-1·cm-1 for SDS and 6. 34 × 104L·mol-1·cm-1 for SDBS. The proposed method has been applied to the determination of anionic surfactants in river water and waste water with satisfactory results.
出处
《环境化学》
CAS
CSCD
北大核心
1997年第5期483-486,共4页
Environmental Chemistry
关键词
阴离子
表面活性剂
磺酞类染料
分光光度法
anionic surfactants, sulphonphthalein dyes, quaternary ammonium salts , spectrophotometry.
