Evaluating liquid CO2 hydrate formation kinetics, morphology, and stability in oceanic sediments on a lab scale using top injection

Comprehensive Review and Perspectives of CO2 Hydrate Storage in Subseafloor Saline Sediments: Formation, Stability, and Optimization Strategies

“…Studies have shown that lower temperatures generally promote the formation of CO 2 hydrates, as the lower thermal energy facilitates the molecular rearrangement necessary for hydrate formation. , Liu et al revealed that a temperature drop from 255 to 235 K significantly reduces the linear growth rate of CO 2 hydrates. In contrast, Dhamu et al reported that the stability of CO 2 hydrates in oceanic sediments at depths of 1km with a higher pressure from 10 MPa and low temperatures between 276.15 to 277.15 K can sustain hydrate stability for extended periods. Yet, the exact temperature conditions for optimal CO 2 hydrate formation and stability are subject to further exploration, especially in subseafloor saline sediments.…”

“…89,186 Ongoing research continuously assesses the long-term risks of NP deployment, emphasizing the need for regular monitoring and investigations to ensure their safe and sustainable use in diverse environments. 20,187 NPs find versatile applications in forming CO 2 hydrates, categorized into distinct functional types, such as promoters, inhibitors, stabilizers and modifiers. First, as promoters, these nanoparticles amplify the rate of CO 2 hydrate formation or reinforce its structure, often comprising materials like metal oxides, carbon-based nanoparticles, or specialized polymers.…”

“…Autoclaves, for example, are commonly used in laboratory settings to subject CO 2 and water mixtures to high pressures, enabling the investigation of CO 2 hydrate formation kinetics and thermodynamics. 187 Pressure vessels and custom-designed high-pressure cells are also employed to replicate specific pressure conditions and study the behavior of CO 2 hydrates under varying pressure regimes to optimize the process. 267 These high-pressure reactor systems are instrumental in advancing CO 2 hydrate formation and developing pressure management strategies for carbon capture and storage applications.…”

“…NPs, like silica NPs, have shown compatibility with marine sediment compositions . Research suggests that these NPs do not typically impose substantial environmental impacts due to their compatibility and potential nontoxic nature. , Ongoing research continuously assesses the long-term risks of NP deployment, emphasizing the need for regular monitoring and investigations to ensure their safe and sustainable use in diverse environments. , …”

“…Issues such as the high cost of large-scale production, the environmental impact of sourcing raw materials, and the technical challenges in maintaining the quality and specifications of NPs and surfactants can hinder their widespread adoption . Additionally, the stability of surfactants under varying environmental conditions, particularly in subseafloor sediments, requires careful consideration to ensure the long-term efficacy of the hydrate storage system, primarily due to the challenges posed by slow CO 2 hydrate formation kinetics and a limited understanding of the stability dynamics of CO 2 hydrates. , Identifying and addressing these challenges is essential for the practical implementation of nanoparticle-assisted surfactant–polymer formulations in enhancing CO 2 hydrate storage solutions.…”