Intensification of ethylene and ethane absorption in N-methyl-2-pyrrolidone (NMP) by adding silver nanoparticles

Abstract

The absorption and solubility of pure ethane and ethylene gases were investigated in an experimental pressure decay setup, where a small amount of silver nanoparticles was added to pure N-methyl-2-pyrrolidone (NMP) solvent. All the experiments were performed at temperatures of 278.15, 298.15 and 328.15 K and different pressures (up to the gases dew points) as well as different concentrations of silver nanoparticles (0.05 and 0.1 g/l). The kinetic data of absorption, Henry’s law constants, heat of absorption, entropy, Gibbs free energy, and ideal selectivity were reported. Also, the effects of temperature, pressure, and nanoparticle concentration on the equilibrium results were evaluated. The absorption results revealed that the presence of small amounts of nanoparticles in the solvent intensified the absorption performance between 1.5–18 % for ethylene and 1–41 % for ethane. The results also showed that the solubility of ethylene in pure solvent and nanofluids was better than that of ethane. Increasing the nanosilver concentration up to 0.1 g/l resulted in reducing the absorption equilibrium time specially for ethylene/nanofluid experiments. Also, the ideal ethylene/ethane selectivity improved by increasing the nanoparticle concentration at the same temperature.