2 石炭層へのガス吸蔵挙動(構造・物性(1))

抄録

Pulse ^1H-NMR spectroscopy was used with the aim to study the phase state of methane absorbed in coal. Spin-spin relaxation time, T2, was employed to evaluate the condition of methane. The signal of methane introduced into coal sample consist of at least three components, that is, relatively slowly decaying component, L1, intermediate component, L2, and rapidly decaying component, L3. The T2 for L1 component shows almost the same value for gaseous methane. This imply that the L1 component arise from the gaseous methane existing in a gap of coal particles. The T2 value for L2 and L3 component is shorter than that for L1 components suggesting the effects of spin-spin interaction, while the relaxation mechanism of gaseous methane mainly affected with spin-rotation interactions. The results indicate that the methane in L2 and L3 component exists in a dense or restrained condition result not only from the adsorption of methane on the surface of coal but also from solid solution in coal.