## 2 Literature Overview  
Over the last several decades, a number of theoretical studies focusing on hydrate film formation along water/guest-fluid interfaces have been carried out by research groups worldwide [8; 9; 10]. The bulk of the studies considered either a planar gas-liquid interface, a water droplet surface in the gas phase, or the gas-bubble interface, with the theoretical research focusing on the impact of heat transfer on the growth of hydrates at the interface. As this paper aims to develop a more realistic kinetic model for hydrate film formation, we will mostly focus on the theoretical investigation by various researchers rather than experimental results. The first theoretical models of hydrate film formation were developed by [PERSON] et al. [8], [PERSON] et al. [9], and [PERSON] et al. [10]; these studies can be broadly grouped together since their models describe the hydrate film as a diffuse layer suspended in the liquid hydrate former. [PERSON] et al. [8] treated each hydrate film as a concentration boundary layer, hypothesizing that water molecules will diffuse into the liquid CO\({}_{2}\) phase and subsequently give rise to hydrate nucleation, with the newly formed hydrate clusters slowly diffusing towards the aqueous phase. [PERSON] et al. [9] extended the model by adding the possibility of hydrate cluster dissociating. [PERSON] et al. [10] \"reversed\" the two models by presuming that hydrate will form more easily in the water-rich phase. However, all of the original three models have been shown to disagree with the experimental observations of a sharp solid-liquid interface and hydrate film tensile strength measurements by [PERSON] et al. [11]  
The second group of researchers utilized models that treated the hydrate film as a solid plate. For example, [PERSON] et al. 1996 [12] and [PERSON] and [PERSON] 1997 [13] modeled the film as a CO\({}_{2}\)-permeable micro-perforated plate model and a water-permeable micro-perforated plate, respectively. Unfortunately, the [PERSON] et al. [12] model failed to explain the driving force for the liquid CO\({}_{2}\) flow through the holes across the hydrate film, and also used the unrealistic assumption of a mosaic water-side surface to explain the melting and crystallization of hydrates. Later, [PERSON] and [PERSON] 1997 [13] proposed a model similar to that of [PERSON] et al. [12] with respect to geometry and structure of the hydrate film. Their model assumes the hydrate film to be a uniform plate with constant thickness and evenly distributed micro-perforations. Their key difference in their description compared to [PERSON] et al. [12] was that it was the liquid water rather than the CO\({}_{2}\) that permeated the hydrate film and filled its capillaries. The process was driven by capillary pressure induced at the interface, with the aqueous phase inside the capillaries being saturated in guest species. The model assumed that CO\({}_{2}\) transfer into the aqueous phase and subsequent hydrate formation and dissociation processes will be rate controlled by mass transfer. A somewhat controversial point of this model was its assumption of hydrate melting and crystallization present even in the case of a vanishing driving force, as well as the lack of any consideration of kinetics governing the two processes. In 1998, [PERSON] suggested a model describing the formation of hydrate film around a CO\({}_{2}\) droplet [14]. This new model was based on three new assumptions introduced to retard the dissolution of CO\({}_{2}\) in water. The first supposition involved the reduction in the droplet surface mobility due to hydrate film formation and the decrease in the convective mass transfer coefficient. The second assumption was the reduction in the solubility of CO\({}_{2}\) due to hydrate film formation, and the third one suggested that the effective viscosity of water and mass diffusion coefficient will increase because of hydrate cluster consumption of CO\({}_{2}\). In 1999, [PERSON] et al.