Kinetic study of carbon dioxide hydrate formation in presence of silver nanoparticles and SDS

Abstract

The effects of synthetized silver nanoparticles and sodium dodecyl sulfate (SDS) on carbon dioxide hydrate formation rate and storage capacity have been studied in this work. Aqueous solution of SDS with concentrations of 300 and 500ppm, suspension of silver nanoparticles with concentrations of 0.000045 and 0.00009M, and the mixture of SDS (500ppm) and silver nanoparticles (0.000045M) were tested in a 460cm3 stirred batch reactor. The experiments were conducted at temperatures (273.65 and 275.65)K and initial cell pressures (2 and 3)MPa. Our results show that SDS and silver nanoparticles do not have significant effect on decreasing the induction time and increasing the storage capacity of CO2 hydrates. However, the mixture of SDS and silver nanoparticles significantly increase the storage capacity of carbon dioxide. A diffusion-reaction kinetics model is used to predict the hydrate growth rate. Analyzing the growth rates at the start of hydrate formation show that, the addition of SDS and silver nanoparticles increases the apparent rate constant and the mixture of SDS and silver nanoparticles is most effective in enhancing the apparent rate constant.