<br/>Over the past years, there has been increasing interest in the study of natural gas hydrates (NGHs) nucleation and growth due to their impact in the oil industry, environmental sciences and potential for gas storage. Most recently, particular attention has been devoted to the discovery and design of molecular additives, which can prevent the build-up of NGHs in subsea pipelines, the main cause of pipeline blockage. Additives such as quaternary ammonium salts (QASs) can bind to NGHs surfaces and change their chemistry and morphology, consequently preventing agglomeration. And although these molecules have been originally designed to prevent hydrate formation/growth, recent studies have shown that some additives will promote NGHs growth instead, which poses a serious limitation to the effective design of additive molecules. Moreover, classical molecular dynamics (MD) simulations of NGHs-additive interactions have allowed for the rationalization of the atomistic details that are behind NGHs inhibition or growth, making classical MD the tool of choice for additive discovery, even though a systematic screening and design of molecular additives is hindered by the empirical nature of classical force fields and the costs of binding energy calculations.<br/>As these limitations go to highlight the need for a new computational framework for additive discovery, we propose a new unbiased approach that will investigate NGHs-additive interactions based on a combination of multiscale techniques. Here, classical MD simulation data is used to reconstruct NGHs surfaces and binding sites. These surfaces are then used for binding energy calculations for QASs of different alkyl chain lengths and to further determine these additives promotion/inhibition performances.  Preliminary results from the characterization of QASs on the hydrate surface in solutions of 0 and 100% watercut will be presented.

High-throughput multiscale approach towards natural gas hydrate additive discovery

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.