IP: 146.185.201.107 On: Mon, 01 Jun 2020 09:05:47 Copyright: American Scientific Publishers Delivered by Ingenta Copyright © 2020 American Scientific Publishers All rights reserved Printed in the United States of America Article Journal of Nanoscience and Nanotechnology Vol. 20, 5473–5477, 2020 www.aspbs.com/jnn Application of Silver Nanofluids on Kinetics of Sulfur Hexafluoride Gas Hydrate Formation Dong Hyun Kim 1 , Kyung Chan Kang 2 , Seong Deok Seo 2 3 , Seung Min Lee 2 , Ji Won Jeong 1 , and Ju Dong Lee 2 ∗ 1 R&D Center, HEBEDENT Co., Ltd., 2, Busandaehak-Ro 63Beon-Gil, Geumjeong-Gu, Busan 46241, Republic of Korea 2 Offshore Plant Resources R&D Center, Korea Institute of Industrial Technology, 16, Mieumsandan 5-Ro 41Beon-Gil, Gangseo-Gu, Busan 46744, Republic of Korea 3 Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Republic of Korea Gas hydrates are nonstoichiometric nano-structured crystalline compounds which are stabilized by gas molecules incorporated in the cages made of hydrogen bonding of water molecules at suitable thermodynamic conditions. The gas hydrate as a technology has been successful for several poten- tial applications in various engineering fields, such as, gas separation, carbon dioxide sequestra- tion, gas storage and transportation, desalination of salt water and wastewater treatment. Recently, metal-based nanofluids are considered as interesting kinetic promoter candidates for accelerating formation of gas hydrates. Although organic-based kinetic promoters are widely studied for the rapid formation of gas hydrates, research of a new material system is still a challenge. In this study, Silver (Ag) nanofluids as kinetic promoter of sulfur hexafluoride (SF 6 ) hydrate were prepared by electrical explosion of pure metal wire in deionized water. The kinetics of SF 6 gas hydrates were evaluated with different concentration of Ag nanofluids at condition of 276 K and 0.7 MPa, respectively. The Ag nanofluids, as kinetic nano-prompter, showed excellent effect on the formation of SF 6 hydrates. Keywords: Gas Hydrates, Sulfur Hexafluoride, Silver Nanofluids, Kinetics. 1. INTRODUCTION Gas hydrates are non-stoichiometric nano-structured crys- talline compounds which are stabilized by gas molecules incorporated in the cages made of hydrogen bonding of water molecules at suitable thermodynamic conditions. They have three basic crystal structures (structure I, struc- ture II, and structure H) which consist of three differ- ent cavies [1]. They have attracted attention because of their great potential to be used as gas capture and sep- aration [2–4], gas storage and transportation [5–7], and desalination [8, 9]. However, the kinetic formation rate of gas hydrates is low for water-immiscible gases. Therefore, this prob- lem can be overcome by using mechanical mixing sys- tem, thermodynamic and kinetic hydrate promoters such organic chemical additives. In organic-based kinetic pro- moters, many researchers have tried to apply various pro- moters. Typical organic-based kinetic promoters for gas ∗ Author to whom correspondence should be addressed. hydrate formation are anionic Sodium Dodecyl Sulfate (SDS), Linear Alkyl Benzene Sulfate (LABS), cationic Cetyl Trimethyl ammonium Bromide (CTAB), and non- ionic surfactants. Such surfactants reduce the surface ten- sion between gas and liquid phases, which enhance the mass transfer from gas to aqueous phase [10]. Recently, studies of inorganic nanoparticles as new kinetic promoters of gas hydrate technology are gradu- ally increasing for several potential applications of gas hydrate technology [11]. Our previous study was reported that hybrid mixture nanopromoter of wet chemical pre- pared copper metal nanopowders and organic surfactants showed excellent effect on the kinetic formation of sulfur hexafluoride (SF 6 ) gas hydrates [12]. One of nanoparticle fabrications, the electric explosion method of metal wire is a top–down physical nanotech- nology for preparation of metal nanoparticles. Especially, electrical explosion of silver (Ag) metal wire in deionized water is a useful simple method to prepare metal nanocol- loids or nanofluids [13]. J. Nanosci. Nanotechnol. 2020, Vol. 20, No. 9 1533-4880/2020/20/5473/005 doi:10.1166/jnn.2020.17629 5473