Abstract Surface activity, foaming ability, and foam stability of SDS and salts mixtures are experimentally studied. It is shown that adding KCl or CaCl2 can increase the surface activity but decrease the foaming ability of SDS solution. The capacity to stabilize SDS foam decreases as KCl＞CaCl2＞NaCl. The SDS foam ageing is delayed due to the crystals blocked in the plateau borders and adsorbed on the surface of bubble films. When the SDS concentration is too high, the foam stability rises only if there are enough crystals in the plateau borders. The influence of crystal structure on foam stability has been investigated by using FESEM. The KDS crystals with lower random close-packing density stabilize SDS foam more efficiently than Ca(DS)2 crystals with higher random close-packing density. The understanding of this study is of great importance for the application of SDS foams in fire extinguishing and upstream petroleum industry.

中文翻译：

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盐在十二烷基硫酸钠稳定泡沫性能中的作用

摘要 实验研究了SDS和盐类混合物的表面活性、发泡能力和泡沫稳定性。结果表明，加入KCl或CaCl2可以提高SDS溶液的表面活性，但会降低其发泡能力。稳定SDS泡沫的能力随着KCl＞CaCl2＞NaCl而降低。由于晶体在高原边界被阻塞并吸附在气泡膜表面，SDS泡沫老化被延迟。当 SDS 浓度过高时，只有在高原边界有足够的晶体，泡沫稳定性才会上升。使用FESEM研究了晶体结构对泡沫稳定性的影响。具有较低随机密堆积密度的 KDS 晶体比具有较高随机密堆积密度的 Ca(DS)2 晶体更有效地稳定 SDS 泡沫。