Naphthenic acids (NAs) are compounds naturally present in most petroleum sources comprised of complex mixtures with a highly variable composition depending on their origin. Their occurrence in crude oil can cause severe corrosion problems and catalysts deactivation, decreasing oil quality and consequently impacting its productivity and economic value. NAs structures also allow them to behave as surfactants, causing the formation and stabilization of emulsions. In face of the ongoing challenge of treatment of water-in-oil (W/O) or oil-in-water (O/W) emulsions in the oil and gas industry, it is important to understand how NAs act in emulsified systems and which acids are present in the interface. Considering that, this review describes the properties of NAs, their role in the formation and stability of oil emulsions, and the modern analytical methods used for the qualitative analysis of such acids.

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环烷酸：形成、在乳液稳定性中的作用以及基于质谱的分析方法的最新进展

环烷酸 (NA) 是大多数石油来源中天然存在的化合物，由复杂的混合物组成，其成分根据其来源而变化很大。它们在原油中的存在会导致严重的腐蚀问题和催化剂失活，降低油品质量，从而影响其生产率和经济价值。NAs 结构还允许它们充当表面活性剂，导致乳液的形成和稳定。面对石油和天然气行业中油包水 (W/O) 或水包油 (O/W) 乳液处理的持续挑战，了解 NA 在乳化系统中的作用以及界面中存在哪些酸。考虑到这一点，本综述描述了 NA 的性质、它们在油乳液形成和稳定性中的作用，以及用于此类酸定性分析的现代分析方法。