Mohr Stephan, Pétuya Rémi, Sarria Juan, Purkayastha Nirupam, Bodnar Scot, Wylde Jonathan, Tsimpanogiannis Ioannis N
Nextmol (Bytelab Solutions SL), Barcelona, Spain.
Clariant Produkte (Deutschland) GmbH, Frankfurt, Germany.
J Chem Phys. 2022 Sep 7;157(9):094703. doi: 10.1063/5.0100260.
We have performed molecular dynamics simulations to study the adsorption of ten hydrate anti-agglomerants onto a mixed methane-propane sII hydrate surface covered by layers of liquid water of various thickness. As a general trend, we found that the more liquid water that is present on the hydrate surface, the less favorable the adsorption becomes even though there are considerable differences between the individual molecules, indicating that the presence and thickness of this liquid water layer are crucial parameters for anti-agglomerant adsorption studies. Additionally, we found that there exists an optimal thickness of the liquid water layer favoring hydrate growth due to the presence of both liquid water and hydrate-forming guest molecules. For all other cases of liquid water layer thickness, hydrate growth is slower due to the limited availability of hydrate-forming guests close to the hydrate formation front. Finally, we investigated the connection between the thickness of the liquid water layer and the degree of subcooling and found a very good agreement between our molecular dynamics simulations and theoretical predictions.
我们进行了分子动力学模拟，以研究十种水合物抗聚剂在覆盖有不同厚度液态水层的甲烷 - 丙烷 sII 型混合水合物表面上的吸附情况。总体趋势是，我们发现水合物表面存在的液态水越多，吸附就越不利，尽管各个分子之间存在相当大的差异，这表明该液态水层的存在和厚度是抗聚剂吸附研究的关键参数。此外，我们发现由于液态水和形成水合物的客体分子的存在，存在一个有利于水合物生长的液态水层最佳厚度。对于液态水层厚度的所有其他情况，由于靠近水合物形成前沿的形成水合物的客体分子可用性有限，水合物生长较慢。最后，我们研究了液态水层厚度与过冷度之间的关系，发现我们的分子动力学模拟与理论预测之间有很好的一致性。
