Abstract

The traditional aqueous film-forming foam extinguishing agent (AFFF) plays an important role in fighting liquid fires, but its environmental hazard are also increasingly prominent. The key component of conventional AFFF is fluorocarbon surfactant containing perfluorinated C8 segment, which is one of the most refractory organic pollutants in the world. In this paper, a perfluorinated branched short-chain alkyl side chain fluorocarbon anionic surfactant with high surface activity and simple synthesis route was prepared. The surface activity and aggregation behavior of the mixed solution of fluorocarbon and hydrocarbon surfactants were studied by surface tension meter and transmission electron microscope (TEM). When the mixture ratio of fluorocarbon and hydrocarbon surfactant reached 1:10, the addition of cetyltrimethylammonium bromide (CTAB) had little effect on the interfacial adsorption, but could significantly reduce the critical micelle concentration (CMC) of fluorocarbon surfactant. Meanwhile, three kinds of environment-friendly AFFF formulations (F-1, F-2, F-3) were designed with the mixed system of different hydrocarbon surfactants and this fluorocarbon anionic surfactant as foaming agents. The foam properties revealed the F-2 possessed excellent foam performance, the initial foam height h₀ was 120 mm, and the 25% drainage time was 240 s, extinguishing time was 30 s, burn-back time was 760 s.

摘要

传统的水成膜泡沫灭火剂（AFFF）在扑救液体火灾中发挥着重要作用，但其环境危害也日益突出。常规水成膜泡沫的关键成分是含全氟C8链段的氟碳表面活性剂，是世界上最难处理的有机污染物之一。本文制备了一种表面活性高、合成路线简单的全氟支链短链烷基侧链氟碳阴离子表面活性剂。采用表面张力仪和透射电子显微镜（TEM）研究了碳氟化合物和碳氢化合物表面活性剂混合溶液的表面活性和聚集行为。当碳氟化合物与碳氢表面活性剂的混合比达到1:10时，十六烷基三甲基溴化铵(CTAB)的加入对界面吸附影响不大，但可显着降低氟碳表面活性剂的临界胶束浓度(CMC)。同时，以不同碳氢化合物表面活性剂和该氟碳阴离子表面活性剂为发泡剂的混合体系，设计了三种环保型AFFF配方（F-1、F-2、F-3）。泡沫性能表明 F-2 具有优异的泡沫性能，初始泡沫高度 F-3)采用不同烃类表面活性剂与该氟碳阴离子表面活性剂作为发泡剂的混合体系设计而成。泡沫性能表明 F-2 具有优异的泡沫性能，初始泡沫高度 F-3)采用不同烃类表面活性剂与该氟碳阴离子表面活性剂作为发泡剂的混合体系设计而成。泡沫性能表明 F-2 具有优异的泡沫性能，初始泡沫高度h ₀为120 mm，25%排水时间为240 s，熄灭时间为30 s，回烧时间为760 s。