The effects of natural parameters and their related properties, on the formation and dissociation of gas hydrates, have been widely investigated and satisfying information can be found elsewhere in literature. Conversely, there is a substantial lack of similar studies related to CO₂/CH₄ replacement processes. This research aims to contribute in this sense and shows replacement tests in presence of two pure silica porous media, whose only difference stays in the size of grains. The results confirmed what asserted in literature for the simple formation of hydrates and provided new insights about the replacement process. It was found that the lower size of grains favoured the formation of hydrates and their stability. Precisely for this reason, the fine sediment hindered the replacement, because the higher stability of methane hydrates reduced the capability of CO₂ molecules to penetrate within the sediment and take the place of methane molecules. This study proved once again that, natural elements capable to act as promoter for the formation of hydrates, often have an inhibiting effect on the replacement processes.

自然参数及其相关性质对天然气水合物形成和分解的影响已被广泛研究，令人满意的信息可以在文献的其他地方找到。_{相反，关于CO 2} /CH ₄的类似研究非常缺乏更换过程。这项研究旨在在这个意义上做出贡献，并展示了在两种纯二氧化硅多孔介质存在下的替代测试，其唯一的区别在于晶粒的大小。结果证实了文献中关于水合物的简单形成的断言，并为替代过程提供了新的见解。发现较小尺寸的晶粒有利于水合物的形成及其稳定性。正是由于这个原因，细小的沉积物阻碍了置换，因为甲烷水合物的较高稳定性降低了CO _2的能力分子渗透到沉积物中并代替甲烷分子。这项研究再次证明，能够作为水合物形成促进剂的天然元素通常对置换过程具有抑制作用。