烷基苯磺酸盐定量分析

摘要

结合同步监控技术,优化纯化工艺,获得总烷基苯磺酸盐活性物组分以及单烷基苯和双烷基苯磺酸盐活性物组分,纯度大于90%;分别以总磺酸盐活性物和单磺酸盐 、双磺酸盐活性物为定量标准物质,对烷基苯磺酸盐样品中的活性物百分比进行高效液相色谱分析.结果表明,烷基苯磺酸盐样品中单磺酸盐的量远高于双磺酸盐;总磺酸盐 、单磺酸盐和双磺酸盐活性物组分均在224 nm处有最大吸收,吸收系数强弱顺序为单磺酸盐 ≈ 总磺酸盐>双磺酸盐;以总磺酸盐和单磺酸盐活性物组分为标准物质,最小检测量为5 mg/L,以双磺酸盐活性物组分为标准物质,最小检测量为10 mg/L;由于双磺酸盐活性物组分紫外吸收系数较弱,导致以总磺酸盐活性物为标准物质测试的百分比结果较同时以单磺酸盐 、双磺酸盐活性物为标准物质时低3%左右.%Combined with synchronized monitoring techniques ,purification processes for active constituent of alkylbenzene sulfonate have been optimized ,and the total alkylbenzene sulfonate ,mono-alkylbenzene sulfonate and di-alkylbenzene sulfonate can be obtained with purity over 90% .With the above active constituents as standard substances respectively ,the determination of alkylbenzene sulfonate content in the original samples was carried out by high performance liquid chromatograph .The results showed the sample contained mono- and di-alkylbenzene sulfonate simultaneously , and the content of mono-alkylbenzene sulfonate was much higher than that of di-alkylbenzene sulfonate .They had maximum absorption at the wavelength of 224 nm , and the absorption coefficients of total alkylbenzene sulfonate and mono-alkylbenzene sulfonate were similar ,higher than that of di-alkylbenzene sulfonate .With total ,mono- and di-alkylbenzene sulfonate as standard substances respectively ,the limits of quantitation were 5 mg/L ,5 mg/L and 10 mg/L ,respectively .The determination result of active constituent was about 3%lower with total alkylbenzene sulfonate as standard substance than that with mono- and di-alkylbenzene sulfonate as standard substances simultaneously ,owing to the weaker absorption coefficient of di-alkylbenzene sulfonate .