Article
Chemistry, Physical
Mengqi Ye, Haixia Zhang, Zongxu Wu, Chenguang Ding, Zhijie Jin, Fang Wang, He Bian
Summary: Supercritical carbon dioxide can be used as a green organic solvent with promising application prospects. This study constructed a C/W microemulsion system using supercritical carbon dioxide and water, and visualized the internal structures and alignment of surfactant molecules. The results showed that the formed C/W microemulsion exhibited better stability and resistance to salt, temperature, and shear rate.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Materials Science, Multidisciplinary
Xiaoling Sun, Dongzi Yu, Jiyin Song, Haijuan Kong, Muhuo Yu
Summary: In this study, PAN-based activated carbon nanofibers were used as a carrier and framework for photocatalysts. TiO2 was deposited on the surface of pre-oxidized PAN nanofibers using supercritical carbon dioxide, and the fibers were activated by heat treatment to prepare TiO2/ACNF. The morphology, structure, and specific surface area of the modified nanofibers were analyzed, and the photocatalytic degradation of methyl orange was tested. The results showed that TiO2 nanoparticles can be uniformly loaded on the surface of pre-oxidized PAN nanofibers after supercritical treatment, and the TiO2/ACNF has a high specific surface area of 422.8 m2/g, exhibiting superior adsorption and photocatalytic degradation performance.
Article
Polymer Science
Ryan R. Larder, Eduards Krumins, Philippa L. Jacob, Kristoffer Kortsen, Robert Cavanagh, Long Jiang, Claudia Vuotto, Iolanda Francolini, Christopher Tuck, Vincenzo Taresco, Steven M. Howdle
Summary: This study presents a novel method for synthesizing polymer-silver composite microparticles using supercritical carbon dioxide, avoiding the use of environmentally harmful solvents. The synthesized composites showed good antimicrobial activity and compatibility in the 3D printing process.
Article
Food Science & Technology
Yujia Liu, Naixin Kang, Haiyang Cheng, Xuebin Chu, Zhengwei Sun, Chunyu Xi
Summary: Protein nanoparticles were prepared using supercritical carbon dioxide treatment, with the CO2 pressure found to modulate the size of nanoparticles. The results suggest the potential for future applications in food and biomedical products.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Yize Zhang, Xingwang Lan, Fanyong Yan, Xingyue He, Juan Wang, Luis Ricardez-Sandoval, Ligong Chen, Guoyi Bai
Summary: The study demonstrates the synthesis of silver nanoparticles using two pyridine-based covalent organic frameworks (COFs) with rich porosity, showing outstanding catalytic activity for the carboxylative cyclization of propargylic amines with CO2. By regulating the position of pyridinic-N in the frameworks, selective confinement of silver sites to specific sizes in different pores is achieved, influencing catalytic activity and stability. The ultrasmall nanoparticles in Ag@2,6-FPP-TAPT exhibit enhanced catalytic activity due to synergistic effects among particle size, mass transfer, adsorption and activation for propargylic amines and CO2, supporting scalable preparative ability with full conversion and high TOF value in continuous-flow conditions.
Article
Chemistry, Physical
Jaideep Mor, Pranav Utpalla, Ravi Kumar, Jitendra Bahadur, Sandeep Kumar Sharma
Summary: ZIF-L is transformed to ZIF-8 through a topotactic phase transformation driven by the removal of hydrogen-bonded linker molecules. Crystalline particles form within the first minute, and leaf-like structures complete their growth within 10 minutes. During the transformation, ZIF-L particles are cleaved and transformed into 3D ZIF-8 nanocrystals.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Hong-Rui Ren, Qin-Qin Xu, Jian-Zhong Yin
Summary: The study used molecular dynamics simulations to investigate the formation and stability mechanism of water-in-carbon dioxide microemulsions with high W-0. The findings revealed the unique interfacial phenomenon of CO2 accumulation at the interface, providing insights for synthesizing high-W-0 microemulsions.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Viktor I. Bogdan, Aleksey E. Koklin, Alexander L. Kustov, Yana A. Pokusaeva, Tatiana V. Bogdan, Leonid M. Kustov
Summary: The reduction of CO2 with hydrogen into CO was studied on alumina-supported Co and Fe catalysts under supercritical conditions. The Co/Al2O3 catalyst showed high selectivity towards methanation, while the Fe/Al2O3 system demonstrated hydrogenation to CO with ethane formation. The study found differences in crystallographic phase features of Fe-containing catalysts leading to different reactions.
Review
Chemistry, Multidisciplinary
Guoli Chen, Rengui Li, Lei Huang
Summary: Photochemical deposition has gained increasing attention as a method for preparing nano-catalysts due to its mild reaction conditions, simplicity, green and safe characteristics, and potential for various applications. This review provides an overview of recent advances in photochemical deposition methods for fabricating heterogeneous catalysts, with a focus on the factors influencing the nucleation and growth of metal nanoparticles. The control of photogenerated charges and triggered photochemical reactions has been shown to be significant in the deposition process.
Article
Chemistry, Multidisciplinary
Hongjiao Li, Yunchang Liang, Wenbo Ju, Oliver Schneider, Ulrich Stimming
Summary: This study utilized electrochemical scanning tunneling microscopy (EC-STM) to monitor the surface evolution of a silver electrode in two different electrochemical environments. The results showed that the silver surface transformed from a polycrystalline structure to a well-defined surface arrangement in both an aqueous sodium hydroxide solution and an ionic liquid. Additionally, cathodic annealing of the polycrystalline silver was found to be a cheap and reliable method to obtain quasi-ordered crystal surfaces.
Review
Chemistry, Multidisciplinary
Paola Franco, Iolanda De Marco
Summary: The use of supercritical micronization/nanonization techniques can improve the efficacy of active compounds in pharmaceuticals, offering numerous advantages over traditional methods.
APPLIED SCIENCES-BASEL
(2021)
Review
Pharmacology & Pharmacy
Rahul Kumar, Amit K. Thakur, Nilanjana Banerjee, Pranava Chaudhari
Summary: Novel particle generation processes of Active Pharmaceutical Ingredient (API)/drug have been extensively explored in recent decades, with Rapid Expansion of Supercritical Solutions (RESS) being a promising technique. This literature review critically examines the application of RESS in the formation of fine particles, discussing the key factors such as solubility of API in SC CO2 and supersaturation that affect particle size.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2021)
Article
Chemistry, Multidisciplinary
Alexey Rybaltovsky, Evgeniy Epifanov, Dmitriy Khmelenin, Andrey Shubny, Yuriy Zavorotny, Vladimir Yusupov, Nikita Minaev
Summary: Two methods are proposed for synthesizing bimetallic Au/Ag nanoparticles, utilizing different geometric configurations and laser sources. The first configuration demonstrates the possibility of obtaining Ag/Au alloy nanoparticles, while the second configuration shows the possibility of obtaining core-shell bimetallic Au/Ag nanoparticles.
Article
Pharmacology & Pharmacy
Thibault Massias, Suenia de Paiva Lacerda, Jacqueline Resende de Azevedo, Jean-Jacques Letourneau, Marie -Alexandrine Bolzinger, Fabienne Espitalier
Summary: Nifedipine, a Class II drug, has poor oral bioavailability, low dissolution rate, and significant hepatic metabolism. Transdermal delivery using super-saturated systems may be a solution but the limiting factor is the physicochemical properties, such as dissolution rate, of Nifedipine. This study explores the use of supercritical carbon dioxide-assisted crystallization process to reduce particle size of Nifedipine. The optimized conditions produced thinner Nifedipine particles and improved dissolution kinetics. The scCO2-RESS process is solvent-free and can produce micronized or nanosized crystals to enhance the properties of poorly water-soluble drugs.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Chemistry, Physical
Victorine Warambourg, Adil Mouahid, Christelle Crampon, Anne Galinier, Magalie Claeys-Bruno, Elisabeth Badens
Summary: The aim of this study was to develop a sterilization process for thermosensitive polymeric materials using supercritical carbon dioxide. The optimal conditions for bacterial reduction, with a reduction of 8.73-log, were found to be a pressure of 110 bar, temperature of 40 degrees C, treatment duration of 20 minutes, and the addition of 200 ppm of H2O2.
JOURNAL OF SUPERCRITICAL FLUIDS
(2023)
Article
Chemistry, Physical
P. Belmonte, J. M. Garcia-Vargas, J. F. Rodriguez, I. Garrido, M. T. Garcia, M. J. Ramos
Summary: In this study, four polythiourethane films with different types of polyols and isocyanates were synthesized, characterized, and foamed. The results showed that the type of isocyanate greatly influenced the crystallinity and stiffness of the polymers, while the type of polyol modified the FT-IR spectra and the decomposition curve of the material with temperature. Furthermore, the choice of isocyanate also affected the properties of the foams obtained from the polymeric material.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Xutao Zhu, Jianguo Yan, Shouchun Liu, Fengling Zhu
Summary: This study experimentally assessed the hydrodynamic characteristics of supercritical-pressure R134a in a horizontal circular tube. It was found that the hydrodynamic characteristic curve of R134a under supercritical pressure does not have a negative-slope region but a transition region. The transition region becomes more evident with increasing heat flux, while it weakens with increasing pressure and inlet temperature. Moreover, the onset of the transition region shifts in the direction of high mass flow rate with increasing heat flux.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Stefania Mottola, Iolanda De Marco
Summary: In this study, corticosteroids were micronized with cyclodextrin using Supercritical Assisted Atomization (SAA), resulting in spherical micrometric particles with improved dissolution time.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Honghai Liu, Yu Xie, Zhilan Li, Xiaokai Zhang
Summary: This study compared the effects of supercritical carbon dioxide dewatering (SCD) and conventional kiln drying (CKD) at a temperature of 55 degrees C on the dewatering rate, moisture transfer and distribution, shrinkage, and stress characteristics of bamboo strips. The results showed that SCD had a faster dewatering rate and lower shrinkage compared to CKD, but was less effective in reducing drying stress in bamboo.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Tahmasb Hatami, Ozan N. Ciftci
Summary: This study fills the gap in previous research by establishing a hierarchy of significance for factors affecting SFE profitability, providing a deeper understanding of how technical and economic factors impact profitability. The findings highlight that the SFE facility becomes profitable when the extractor capacity surpasses 42 L.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Tingshan Guo, Chuang He, Zhiyuan Liang, Qinxin Zhao
Summary: The initial oxidation behavior of Fe10Cr and Fe20Cr alloys in supercritical H2O and supercritical CO2 with O2 has been investigated. The results show that O2 has the highest adsorption energy on FeCr alloys and reacts faster than H2O and CO2.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Vikash Chandra Roy, Jin-Seok Park, Ahmed Redwan Haque, Md Sadek Ali, Hee-Jeong Lee, Byung-Soo Chun
Summary: This research aimed to valorize brewery spent grain (BSG) using subcritical water hydrolysis (SWH) modified by six different natural deep eutectic solvents (DES) and determining their bipotentialities. The findings showed that BSG hydrolysates obtained through DES-induced SWH contained high levels of sugars, proteins, flavonoids, phenolic compounds, and essential amino acids. The hydrolysates also demonstrated antimicrobial activities, and the presence of bioactive compounds was confirmed through FT-IR analysis. This comprehensive profiling of bioactive compounds from BSG using DES-mediated SWH can contribute to the efficient valorization of BSG for industrial purposes.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Kailiang Zhang, Hanyu Wang, Tong Liu, Zhu Wang, Lvxing Wang, Ping Fan, Feng Chen, Mingqiang Zhong, Bozhen Wu, Shanqiu Liu, Jintao Yang
Summary: This study investigates the influence of foam cell structure on the electromagnetic interference shielding performance of conductive polymer composite foam. The results suggest that foamed composites exhibit improved EMI shielding performance, and bimodal cell foams have higher electric conductivity but lower EMI shielding compared to uniform cell foams.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Jaromir Valtr, Petr Roztocil, David Dasek, Radek Musalek, Frantisek Lukac, Jakub Klecka, Marek Janata, Mariana Arnoult-Ruzickova, Eva Mistova, Ludek Jelinek, Petr Sajdl, Jan Macak
Summary: This paper focuses on the design of an experimental facility for in-situ electrochemical testing at supercritical water conditions, including the design of the electrode system and surface insulation coating for electrode leads.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)
Article
Chemistry, Physical
Richard Djimasbe, Mikhail A. Varfolomeev, Nailya M. Khasanova, Ameen A. Al-Muntaser, Rustam R. Davletshin, Muneer A. Suwaid, Gazinur Z. Mingazov
Summary: This study confirms the capability of supercritical water to generate active hydrogen that interacts with different fractions in unconventional feedstocks, leading to synthetic oil production during hydrothermal reactions. The findings suggest that a maximum yield of 16.78% can be achieved at a temperature of 380 oC and a reaction time of 1-12 hours.
JOURNAL OF SUPERCRITICAL FLUIDS
(2024)