Article
Engineering, Chemical
Ryosuke Ezure, Yuma Arai, Daiki Nakano, Hiroyuki Komatsu, Hideo Tajima
Summary: Hydrate-based gas separation is a method of separating gas mixtures based on their thermodynamic properties. This study proposes a new process for gas absorption and desorption under constant pressure with rising temperature. Theoretical calculations and experimental verification showed that SF6 can be concentrated up to 90% using this process.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Engineering, Chemical
Zucheng Cheng, Weiguo Liu, Shaohua Li, Sijia Wang, Yingying Liu, Xiang Sun, Cong Chen, Lanlan Jiang, Yongchen Song
Summary: This study evaluated the performance of SDS in the separation efficiency of simulated biogas. The experimental results showed that higher driving forces led to a significant increase in gas capture, dominated by the CH4 component. Hydrate growth mainly occurred in the liquid phase, and the separation factor was positively correlated with the induction time. Gas capture per unit volume of solution could be improved at higher gas-liquid ratios, while high-pressure failure behavior was observed. The defoamer had no significant effect on hydrate generation kinetics and separation efficiency.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Thermodynamics
Wenlong Jia, Fan Yang, Changjun Li, Ting Huang, Shuoshuo Song
Summary: A unified thermodynamic model is proposed in this paper to describe the multiple interactions of acid gas/water/alcohol/electrolyte components on gas, liquid, and hydrate phases. The model achieves high accuracy in predicting hydrate formation conditions and demonstrates better performance in mixtures containing alcohols and/or electrolytes.
Article
Energy & Fuels
Namrata Gaikwad, Jitendra Sangwai, Praveen Linga, Rajnish Kumar
Summary: In this study, methane separation from CMM gas mixture was achieved by forming sII and sH hydrates with the use of different thermodynamic promoters at moderate temperature and pressure conditions. The formation of sII hydrate showed better methane recovery, while the formation of sH hydrate demonstrated a better separation factor. The use of water-soluble hydrate promoter sodium dodecyl sulfate (SDS) enhanced the rate of hydrate formation for better separation efficiency.
Article
Energy & Fuels
Erfan Khanmohammadian, Mohsen Mohammadi, Rohallah Hashemi, Sina Eslami, Mohammad Reza Ehsani
Summary: In this study, the separation of CO2 gas from a CO2/CH4 mixture was investigated using the gas hydrate formation method. Silica and APTES surface-modified silica nanoparticles with potassium hydroxide were used as additives. The presence of silica improved gas consumption, separation factor, and recovery factor. The optimal nanofluids with silica and potassium hydroxide showed a significant increase in gas consumption, separation factor, and recovery factor compared to pure water. The gas-liquid ratio and initial pressure affected the gas consumption, separation, and recovery factors.
Article
Thermodynamics
Xiaoya Zang, Jing Wang, Yong He, Xuebing Zhou, Deqing Liang
Summary: In this study, TBAB hydrates were synthesized and their carbon capture capacity from a ternary gas mixture of CH4/CO2/N-2 was investigated. The addition of TBAB increased the specific surface area of the hydrate crystals and transformed the hydrate structure. These findings are important for the development of hydrate gas separation technology.
Article
Green & Sustainable Science & Technology
Hongsheng Dong, Jiaqi Wang, Zhuoxue Xie, Bin Wang, Lunxiang Zhang, Quan Shi
Summary: This review discusses the potential applications of gas hydrates in energy and environmental fields, highlighting their advantages in gas storage, gas separation, wastewater treatment, and other areas. Challenges, limitations, and future directions for each application are also explored in the paper.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Engineering, Chemical
Awan Bhati, Aritra Kar, Vaibhav Bahadur
Summary: This study predicts the performance of a bubble column reactor (BCR) for CO2 hydrate formation from flue gas and pure CO2 streams using a modeling framework. The study focuses on two performance parameters: gas consumption rate and conversion factor. The analysis shows that increasing pressure, decreasing temperature, and increasing CO2 mole fraction lead to higher performance parameters. This study provides a basis for the design and operation of BCRs for CO2 hydrates-based CCS applications.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Hyunglok Chu, Kyuchul Shin
Summary: Xenon (Xe) and krypton (Kr) are used in various important industries, but their separation is energy-intensive. This study shows that clathrate hydrates can be used for cost-effective Xe-Kr separation. The hydrate-based approach captures Xe selectively and requires milder temperature conditions compared to cryogenic distillation. It suggests that this method is an excellent alternative to the energy-intensive cryogenic distillation.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Review
Polymer Science
Alsu Venerovna Fakhreeva, Vasily Viktorovich Nosov, Alexander Iosifovich Voloshin, Vladimir Anatolyevich Dokichev
Summary: This review discusses the types and applications of chemical inhibitors of gas hydrate formation in the oil and gas industry. It analyzes the development of new types of environmentally safe green kinetic hydrate inhibitors (KHIs) based on biopolymers. The article considers the structure, physicochemical properties, efficiency, and commercial prospects of polysaccharides in preventing and controlling gas hydrate formation. It also presents recent research on cost-effective, efficient, and biodegradable KHIs for industrial applications in the oil and gas industry.
Article
Chemistry, Multidisciplinary
Wonhee Lee, Seung Hyun Moon, Dong-Woo Cho, Taesung Jung, Seong-Pil Kang
Summary: Hydrate-based gas separation (HBGS) is an alternative method for the separation and recovery of powerful greenhouse gases HCFCs. This study investigated the hydrate phase equilibria, dissociation enthalpies, and crystal structures of different HCFC compounds and mixtures. The kinetic formation of hydrates and their separation performance were examined, revealing the significant influence of initial system pressure.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2022)
Article
Engineering, Chemical
Azam Aydani, Adele Brunetti, Hafez Maghsoudi, Giuseppe Barbieri
Summary: This paper investigates the impact of different gas mixtures on CO2 separation using an SSZ-13 zeolite membrane, showing good performance at 30 degrees Celsius and 200 kPa pressure, with improved selectivity for various mixed gases. The membrane demonstrated consistent CO2 permeance while reducing the permeance of other gases, leading to increased selectivity across different gas compositions.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Energy & Fuels
Yingmei Wang, Aili Niu, Wenze Jiao, Ji Chen, Peng Zhang, Jinping Li
Summary: Carbon dioxide hydrate formation rate is improved by using different accelerator systems. The combination of nanographite-TBAB and SDS-TBAB shows better performance in reducing the nucleation time. TBAB shows the best nucleation amount, formation rate, and conversion rate among the single acceleration systems.
Article
Chemistry, Multidisciplinary
Gyeol Ko, Woojin Go, Yongwon Seo
Summary: The time-dependent selectivity of SF6 in the hydrate-based gas separation process was investigated through experimental and computational approaches. The study found that there was no significant kinetic selectivity difference between SF6 and N2 during hydrate formation and dissociation, with the SF6/N2 ratio in the hydrate structure remaining constant over time. These findings contribute to the development of the hydrate-based SF6 separation process by providing insights into guest-filling and guest-liberating behaviors during formation and dissociation.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Chemistry, Organic
Sungjin Kim, Pavel Nagorny
Summary: This manuscript reports on the electrochemical synthesis of 17 different glycosyl fluorides in yields of 73-98%, using SF6 as an inexpensive and safe fluorinating agent. Mechanistic studies suggest that the active fluorinating species generated through the cathodic reduction of SF6 are transient under these reductive conditions and that the sulfur and fluoride byproducts are effectively scavenged by Zn(II) to generate harmless salts.
Article
Engineering, Environmental
Wonjung Choi, Woojin Go, Yohan Lee, Junghoon Mok, Yongwon Seo
Summary: This study investigated the kinetics of guest exchange in sII hydrate - flue gas replacement and elucidated the replacement mechanism and guest exchange characteristics. The results showed that at higher pressure during replacement, increased CO2 inclusion led to higher production of CH4 and C3H8 and a lower N-2/CO2 ratio in the hydrate phase. Additionally, molecular dynamics simulations demonstrated that the expansion or shrinkage of hydrate cages caused by guest exchange had a significant impact on the lattice parameter of the replaced hydrates.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Thermodynamics
Joonseop Lee, Dongyoung Lee, Yongwon Seo
Summary: This study investigated the complex phase behavior and structures of natural gas hydrates containing large molecule guest substances (LMGSs). Methylcyclopentane (MCP) and 2,2-dimethylbutane (neohexane, NH) were chosen as LMGSs for CH4 (90%) + C3H8 (10%) hydrates. The presence of LMGSs did not affect the equilibrium curves of the CH4 + C3H8 hydrates, with CH4 and LMGSs primarily in sH and CH4 and C3H8 encapsulated in sII. The experimental results provide insights into the role of LMGSs in natural gas hydrates.
Article
Multidisciplinary Sciences
Sung Eun Kim, Yongwon Seo, Junshik Hwang, Hongkyu Yoon, Jonghyun Lee
Summary: Stochastic network modeling is often limited by high computational costs, but this study shows that DCGANs can effectively reproduce drainage networks using a novel connectivity-informed method. By converting drainage network images to directional information and training the network with different samples, DCGANs outperformed traditional methods in generating accurate drainage networks. This highlights the potential of DCGANs in high contrast images common in earth and material sciences.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Environmental
Junghoon Mok, Wonjung Choi, Yongwon Seo
Summary: This study investigated the thermodynamic stability and kinetic growth behavior of HFC-152a hydrate, finding that HFC-152a hydrate has a higher hydration capacity in the presence of NaCl. The results suggest that HFC-152a may be a superior candidate for the HBD process.
Article
Thermodynamics
Junghoon Mok, Wonjung Choi, Jonghyuk Lee, Yongwon Seo
Summary: The guest swapping process of CH4 - CO2 + N-2 replacement in NGH reservoirs can be influenced by pressure and temperature conditions, leading to accelerated CO2 and enhanced N-2 inclusion during the replacement process. This study provides valuable insights into the replacement mechanism occurring in NGH reservoirs with different conditions.
Article
Engineering, Environmental
Woojin Go, Dongyoung Lee, Yongwon Seo
Summary: The study suggests that glycine is the best kinetic hydrate inhibitor among urea, acetamide, and glycine, while combinations of urea and acetamide, urea and glycine, and acetamide and glycine, show synergistic inhibition effects on CH4 hydrate. Among these combinations, urea and acetamide exhibit the best synergism. The findings also highlight the potential of hydrophilic monomeric substances as effective KHIs and propose a new method to understand the mechanism of hydrate inhibition through experimental and computational analyses.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Chemical
Junghoon Mok, Wonjung Choi, Yongwon Seo
Summary: This study examined the thermodynamic and kinetic features of different gas hydrate formers to determine the energy-efficient gaseous hydrate former for hydrate-based desalination (HBD). The results showed that the efficiency of HBD was affected by factors such as initial salinity, operating pressure, and initial subcooling temperature. The study also found that the thermodynamic stability and intrinsic formation kinetics of gas hydrates significantly impacted HBD efficiency.
Article
Thermodynamics
Junghoon Mok, Wonjung Choi, Yongwon Seo
Summary: This study closely investigated the dissociation behavior and time-dependent guest distributions of methane (CH4) hydrate after injecting gaseous N-2 at different temperatures and pressures. Results showed that higher temperature and lower N-2 injecting pressure accelerated the dissociation kinetics of CH4 hydrate. Raman and NMR spectra confirmed the immediate capture of N-2 molecules in hydrate cages at 268.8 K, with N-2 incorporation increasing at higher pressure. C-13 NMR spectra revealed N-2-induced structural transitions in hydrates and the preferential capture of N-2 in small cages. The findings provide insights into the roles of N-2 molecules in inhibitor injection and CH4 - CO2 + N-2 replacement methods for gas hydrate exploitation.
Article
Green & Sustainable Science & Technology
Jungjoon Park, Joon Ho Park, Dongyoung Lee, Yongwon Seo, Yong Tae Kang
Summary: Hydrate-based CO2 capture technology has vast potential and cost effectiveness. However, the direct capture and utilization of hydrate slurries are challenging. Thermodynamic promoters have been introduced to alleviate the formation conditions. By evaluating key parameters, optimal conditions for hydrate slurry-based cold thermal transportation are determined. It is proposed to replace conventional systems with a CO2 hydrate slurry cooling system, demonstrating a significant reduction in energy consumption.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Environmental Sciences
Wonjung Choi, Joonseop Lee, Young-Gyun Kim, Hanwoong Kim, Tae Siek Rhee, Young Keun Jin, Ji-Hoon Kim, Yongwon Seo
Summary: This study investigated the thermodynamic and structural characteristics of NGHs retrieved from the Chukchi Sea, finding that NGHs from AM03 and AM06 were almost identical in composition, structure, and environment. An abnormal salinity enrichment in the sediment of AM06 was discovered, which may induce the dissociation of NGHs at a lower temperature.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Chemistry, Multidisciplinary
Gyeol Ko, Woojin Go, Yongwon Seo
Summary: The time-dependent selectivity of SF6 in the hydrate-based gas separation process was investigated through experimental and computational approaches. The study found that there was no significant kinetic selectivity difference between SF6 and N2 during hydrate formation and dissociation, with the SF6/N2 ratio in the hydrate structure remaining constant over time. These findings contribute to the development of the hydrate-based SF6 separation process by providing insights into guest-filling and guest-liberating behaviors during formation and dissociation.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Engineering, Environmental
Abdolreza Farhadian, Woojin Go, Soyeong Yun, Alireza Rahimi, Mohammad Reza Nabid, Danial Iravani, Yongwon Seo
Summary: In this study, the performance of newly synthesized waterborne polyurethanes (WPUs) as dual-function gas hydrate and corrosion inhibitors was evaluated through experimental and computational approaches. The results showed that WPUs effectively inhibited hydrate formation and protected against corrosive gases.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Environmental
Hyuk-Jun Noh, Dongyoung Lee, Woojin Go, Gyucheol Choi, Yoon-Kwang Im, Javeed Mahmood, Yongwon Seo, Jong-Beom Baek
Summary: Fused aromatic networks (FANs) have attracted attention due to their electronic properties and stability. 3D organic networks and 2D layered structures were found to be effective gas hydrate inhibitors with outstanding stability under high-pressure/low-temperature conditions.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Thermodynamics
Woojin Go, Soyeong Yun, Dongyoung Lee, Yongwon Seo
Summary: This study evaluated easily decomposable monomeric substances as kinetic hydrate inhibitors for CO2 hydrate. Experimental and computational results showed that glycine exhibited the best inhibition effect among single inhibitors, and combinations of urea with acetamide and acetamide with glycine had synergistic inhibition effects on CO2 hydrate. Molecular dynamics simulations provided insights into the nucleation and formation behaviors of CO2 hydrate in the presence of inhibitors. The findings contribute to the development of new biodegradable CO2 hydrate inhibitors and enhance the safety of CO2 transportation and storage.
Article
Chemistry, Physical
Junghoon Mok, Junkyu Lim, Wonjung Choi, Soyeong Yun, Joonseop Lee, Gyeol Ko, Yongwon Seo
Summary: A new sI-sII dual hydrate former was investigated for its potential significance in gas separation, showing that external guests like CH4 and N-2 can promote the formation of sII hydrates with CHClF2. The study revealed the thermodynamic and structural features of CHClF2 hydrates, providing insights for understanding and designing the hydrate-based CHClF2 separation process.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
