分光光度法测定水中微量阴离子表面活性剂  

Determination of slight amount of anionic surfactants in water by spectrophotometry

作　　者：何晓玲[1] 

机构地区：[1]淮北师范大学化学与材料科学学院,安徽淮北235000

出　　处：《日用化学工业》2012年第1期72-75,共4页China Surfactant Detergent & Cosmetics

摘　　要：在用HCl溶液调节pH=12.0的NaOH溶液中,5-甲基-2-[3-(4-苯基-2-噻唑基)三氮烯基]苯磺酸(MPTTBSA)与氯化十六烷基吡啶(CPC)形成离子缔合物MPTTBSA-CPC。在该溶液中加入阴离子表面活性剂时,能定量置换出离子缔合物中的MPTTBSA,使缔合物在最大吸收波长556 nm处的吸光度下降,阴离子表面活性剂的浓度与溶液的褪色程度呈良好线性关系,从而建立了阴离子表面活性剂光度测定法。实验结果表明,十二烷基磺酸钠(SLS)和十二烷基苯磺酸钠(SDBS)的表观摩尔吸光系数分别为1.24×104 L·mol-1·cm-1和1.07×104 L·mol-1·cm-1,在0～2.5×10-5 mol·L-1范围内服从比尔定律。该方法应用于生活污水中微量阴离子表面活性剂(以SLS计)的测定,结果与亚甲基蓝法测定结果基本一致。In an aqueous solution of NaOH with pH adjusted to 12 by HCI, cetylpyridinium chloride （CPC） was added together with a solution of 5 - methyl - 2 - [ 3 - （4 - phenylthiazol - 2 - yl ） triazenyl ] benzenesulfonic acid （ MPTTBSA）, and an ion - associate complex MPTTBSA - CPC was formed. When an anionic surfactant was introduced into the above -said solution, MPTTBSA in the ion -associate complex will be replaced quantitatively by the anionic surfactant, and absorhance at maximum absorbing wavelength 556 nm of MprITBSA - CPC will decline. The absorbance decrease is proportional to concentration of anionic surfaetant with good linearity. Based on this phenomenon, a photometric method for determining the anionic surfactant content in water was established. Experimental results showed that the apparent molar absorbance index for anionic surfactant sodium lauryl sulfonate （SIS） and sodium dodecyl benzene sulfonate （SDBS） is 1.24 × 104 L · mol^-1 · cm^-1 and 1.07 × 104 L · mol^-1 · cm^-1 respectively and they follow Beer＇ s law within range of 0- 2.5 × 10-5 L · mol^-1 · cm^-1. The method has been applied to determination of slight amount of anionic surfactants SIS in waste water samples. The determination results are virtually consistent with that determined by methylene blue method.

关 键 词：阴离子表面活性剂 氯化十六烷基吡啶 分光光度法 5-甲基-2-[3-(4-苯基-2-噻唑基)三氮烯基]苯磺酸 

分 类 号：X832[环境科学与工程—环境工程]