Session 5 - Oral 4
Recyclable and Efficient Hydrate Promoter Based on the Magnetic Iron Oxide Nanoparticle Coated with SDS
Chen Chen, Haoyu Yuan, Fei Wang
College of Electromechanical Engineering, Qingdao University of Science & Technology, Qingdao 266061, China.
Abstract：Except as a form of energy, hydrate is also an effective medium for gas separation, desalination, gas storage and so on. However, the low reaction rate and water conversion have hindered the industrialization of hydrate-based technology. To promote the formation of hydrate, multifarious surfactants have been studied and the sodium dodecyl sulfonate (SDS) shows more effective promotion effect than others. Nevertheless, for the hydrate promoted by the SDS, the resulting foam during the dissociation reduces not only the economic effectiveness but the usability. To increase the recyclability, a magnetic iron oxide nanoparticle coated with SDS (SDS@Fe3O4) was synthesized and then used in the methane hydrate formation and cycle experiments in this paper. We firstly synthesized the magnetic iron oxide nanoparticle (MION) by the co-precipitation method and then coated the surface of MION with SDS. Then the methane hydrate formation was conducted in the presence of SDS@Fe3O4 and formation time is shortened to 20 min at the concentration of 2 g/L of SDS@Fe3O4. To examine the recyclability, SDS@Fe3O4 was collected by magnet after the hydrate dissociation and then was reused for next hydrate formation. After 5 cycles, although the formation time increased to 60 min, the methane storage capacity also reached 150 v/v. And the TGA of collected SDS@Fe3O4 for each cycle of hydrate formation-dissociation showed that the amount of SDS on the surface of SDS@Fe3O4 decreased cycle by cycle. Finally, a series of hydrate formation with SDS@Fe3O4, which is coated by different of amounts of SDS, showed that the formation time is consistent with the cycle experiments. To sum up, by taking the advantage of magnetism of MION, SDS@Fe3O4 can be recycled and reused for the hydrate formation, but the cycle experiments could reduce the amount of SDS of the SDS@Fe3O4.
Key words: methane hydrate, SDS, recyclability, iron oxide nanoparticle