烷基胺插层蒙脱土的阳离子交换容量研究

针对烷基胺作为插层抑制剂抑制黏土矿物水化膨胀缺少定量评价方法的问题，开展了烷基胺（己二胺和支化聚乙烯亚胺）插层蒙脱土的阳离子交换容量研究，研究中采用了红外光谱法表征了烷基胺-蒙脱土复合物，采用了不同阳离子交换容量法测量了烷基胺插层蒙脱土复合物的CEC值，并且通过光电子能谱法进行了定性验证。研究发现，氯化铵-乙酸铵法不仅能准确测量蒙脱土的CEC值，也能准确测量烷基胺-蒙脱土复合物的CEC值。支化聚乙烯亚胺比己二胺能置换更多的交换阳离子，暗示了伯胺基团数量越多，抑制性能越好。因此氯化铵-乙酸铵法可以定量测定烷基胺插层蒙脱土复合物的CEC值，为评价页岩插层剂的抑制性能提供一个准确的定量评价方法。

Study of Cation-exchange Capacity in Alkylamine Intercalation of Montmorillonite

In view of the lack of quantitative assessment methods for alkylamine as an intercalation inhibitor to inhibit the hydration expansion of clay minerals, the cation-exchange capacity (CEC) of intercalation of montmorillonite with alkylamine (hexamethylenediamine and branched polyethyleneimine) was studied. The alkylamine montmorillonite composite was characterized by infrared spectroscopy. The CEC value of the alkylamine-intercalated montmorillonite composite was measured by different cation-exchange capacity methods and qualitatively verified by photoelectron spectroscopy. It was found that the ammonium chloride-ammonium acetate method could not only accurately measure the CEC value of montmorillonite but also accurately measure the CEC value of the alkylamine montmorillonite composite. Branched polyethyleneimine can displace a higher number of exchangeable cations than hexamethylene diamine, suggesting that with increasing number of primary amine groups, the inhibition performance improves. Therefore, the CEC value of alkylamine-intercalated montmorillonite composites can be quantitatively determined using the ammonium chloride-ammonium acetate method, which is an accurate quantitative method for assessing the inhibition performance of shale intercalation agents.