Clathrate hydrate

Composite number

Oceanography

Physics

Geology

Carbon fibers

Composite material

Organic chemistry

Inorganic chemistry

Chemistry

Materials science

Hydrate

Greenhouse gas

Amino acid

Methane

Carbon dioxide

Biochemistry

Natural gas

Isochoric process

Thermodynamics

Scientific Reports

Storage of greenhouse gases in the form of gas hydrates is attractive and is being pursued rigorously in recent times. However, slow formation rate and inefficient water to hydrate conversion are the main hindering factors. In this report, we examine the role of two amino acids (0.5 wt%), l-methionine (l-met) and l-phenylalanine (l-phe) on the formation of gas hydrates using methane (CH 4 ), carbon dioxide (CO 2 ) and their mixtures as guest molecules. Experiments are conducted under non-stirred and isochoric configurations. The hydrate conversion efficiency of both amino acids is identical for hydrates formed with CH 4 and mixture of (CO 2 +CH 4 ). However, the hydrate conversion is significantly less in CO 2 hydrates in l-phe system. Addition of amino acids to the water dramatically improved the kinetics of hydrate formation and 90% of maximum gas uptake in hydrate phase occurred in less than an hour. The water to hydrate conversion is also very efficient (&gt;85%) in the presence of amino acids. Therefore, the amino acids containing systems are suitable for storing both CH 4 and CO 2 gases. The gas hydrates were characterised using powder x-ray diffraction (XRD) and Raman spectroscopic measurements. These measurements indicate the formation of sI hydrates and encasing of gas molecules as guests.

Clathrate Hydrates of Greenhouse Gases in the Presence of Natural Amino Acids: Storage, Transportation and Separation Applications