脂肪酸盐生烃热模拟研究及其意义

干酪根晚期生油说很难圆满解释碳酸盐岩的生烃机制。本文从新的视角探讨了在碳酸盐岩中还存在一类潜在的生烃母质-脂肪酸盐。由于脂肪酸盐物化性质独特，很难从地质体中得到纯脂肪酸盐，因此我们采用了化学合成方法制备硬脂酸镁（ＲＣＯＯ）２Ｍｇ，并对硬脂酸镁、硬脂酸及硬脂酸镁加碳酸钙三个系列的样品进行了３００℃和３５０℃的常规热解实验；实验结果表明脂肪酸盐在热解温度下能够生成烃类物质，并且脂肪酸盐的烃类转化率明显高于脂肪酸。脂肪酸盐的热解断裂方式中α>β>γ，与脂肪酸的断裂方式相比，其β和γ断裂方式较强。这一实验结果可能会对碳酸盐岩的评价提供新的启示。

Study on Laboratory Simulation of the Hydrocarbon Formation from Salts of Fatty Acids

It isn t very satisfactory to explain the hydrocarbon formation in carbonate rocks with thermal evo-lution of kerogen. In this paper a tentative viewpoint was proposed that there is a kind of potential hy-drocarbon generation matters(salt of fatty acid)in carbonate rocks,for it is of special physical and chemi-cal properties, it is very difficult to obtain the pure salt of fatty acid from sedimentary formation. Thus,we prepared magnesium stearate by chemical synthesis. Magnesium stearte, stearic acid and magnesiumstearate plus CaCO₃ were used as simulation samples at 3000℃and 3500℃.The results of the simulationindicated that hydrocarbon conversion ratio of magnesium stearate is higher than that of tearic acid. Thedistribution of reaction products suggested that alpha cleavage is predominant process, in the meantime,βandγ-cracking has also an obvious preponderance. From the experiments of the salt of fatty acid, thenew enlightenment will be gained about hydrocarbon generation in carbonate rocks.