Article
Engineering, Chemical
Fei Huang, Timothy D. Largier, Wayz Khan, Wenjian Zheng, Chris J. Cornelius
Summary: 6FDA-DABA (6FD) polyimide, polyphenylene (PP), and multiblock copolymer (6FD-PP) materials were synthesized using sequential polycondensation and Diels-Alder reactions. The solubility parameter differences between PP and 6FD led to immiscibility, while 6FD-PP multiblock copolymer solutions were clear. The morphology and gas separation performance of the copolymers were studied.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Article
Polymer Science
Sharon Lin, Taigyu Joo, Francesco M. Benedetti, Laura C. Chen, Albert X. Wu, Katherine Mizrahi Rodriguez, Qihui Qian, Cara M. Doherty, Zachary P. Smith
Summary: This study investigated the use of thermally labile moiety t-BOC to protect hydroxyl groups on polymers, and the subsequent removal of t-BOC moieties through thermal treatment to alter the physical packing structure and gas transport properties of the polymer. While this approach can manipulate free volume and gas transport performance in glassy polymers, more robust polymer systems are needed to maintain the nascent free volume architecture generated by this method in linear polyimides.
Article
Engineering, Chemical
Mahmoud A. Abdulhamid, Giuseppe Genduso, Xiaohua Ma, Ingo Pinnau
Summary: A sulfonic acid-functionalized trimethyl-substituted polyimide showed lower gas permeability and higher gas pair selectivity due to higher diffusion selectivity and strong hydrogen bonding induced by -SO3H functionalization. Competitive sorption effects and CO2-induced polymer matrix plasticization in gas mixture systems reduced the polymer selectivity.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Engineering, Chemical
Shan Xu, Xiaolong Ren, Ning Zhao, Lei Wu, Zhiguang Zhang, Yanfang Fan, Nanwen Li
Summary: A high-performance crosslinked brominated 6FDA-based polyimide membrane was developed by tuning the permeability and selectivity through introducing bromine atoms into the polyimide structure. The crosslinking reaction greatly stabilized the membrane performance against plasticization under high CO2 feed pressure. This study provides a facile approach for the preparation of high-performance gas separation polymeric membranes with enhanced plasticization resistance.
JOURNAL OF MEMBRANE SCIENCE
(2021)
Article
Engineering, Chemical
Shan Xu, Ning Zhao, Lei Wu, Shuanyan Kang, Zhiguang Zhang, Guolong Huo, Zhongde Dai, Nanwen Li
Summary: Optimizing the microstructure of carbon molecular sieve (CMS) membranes can improve gas separation performance. This study demonstrates that using a thermally crosslinkable precursor can enhance the permeability and selectivity of CMS membranes.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Chaohua Song, Longfei Peng, Yinhui Li, Yawei Du, Zan Chen, Weixin Li, Cuijia Duan, Biao Yuan, Shuo Yan, Sibudjing Kawi
Summary: Novel hypercrosslinked polymers (HCPs) incorporating 6FDA-based polyimide (PI) MMMs were prepared via a casting method for enhancing gas transport. The addition of HCPs effectively promotes gas permeability and maintains ideal selectivity, making them potential candidates for gas separation in natural gas purification and O-2 enrichment.
Article
Engineering, Chemical
Dongyun Wu, Beibei Zhang, Jun Yuan, Chunhai Yi
Summary: In this study, co-polyimides were prepared by introducing four different diamine monomers into 6FDA-Durene. The effects of diamine monomer geometry on the free volume elements and gas transport properties of the synthesized membranes were systematically investigated. The results showed that gas separation properties of the polyimide membranes can be effectively adjusted by tuning the monomer structure.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Engineering, Chemical
Beibei Zhang, Jie Qiao, Chenxi Dong, Chunhai Yi, Suitao Qi, Bolun Yang
Summary: The introduction of crown ether into the polymeric backbone can enhance the chains packing density, reducing d-spacing and accessible fractional free volume. The membrane showed typical molecular sieving separation mechanism with permeabilities in the order of He > H-2 > CO2 > N-2 > CH4. Incorporation of DB21C7 improved diffusion selectivity and solubility selectivity, leading to significant selectivity increases in various gas pairs compared to non-crown ether contained polyimide membrane. Membrane material design for high purity gas requirement may benefit from introducing crown ether moiety into the polymeric backbone.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Engineering, Chemical
Zhongyun Liu, Wulin Qiu, Wenying Quan, Yang Liu, William J. Koros
Summary: Thermally cross-linkable 6FDA-based polyimides containing carboxyl groups were synthesized and cross-linked to dense films via decarboxylation-induced thermal crosslinking. The content of 3,5-diaminobenzoic acid significantly affected the structure evolution during the crosslinking process. These materials provide attractive gas separation performance and plasticization resistance, making them a versatile platform for various aggressive natural gas feeds encountered in practice.
JOURNAL OF MEMBRANE SCIENCE
(2021)
Article
Engineering, Chemical
Peiyu Jia, Junjie Liu, Jingjing Kong, Mingming Hu, Ning Qi, Zhiquan Chen, Shan Xu, Nanwen Li
Summary: By adding different diamine monomers containing special functional groups to copolyimide membranes, the ultramicropore structures can be tailored, thus affecting gas permeation and selectivity.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Chemical
Jingjing Kong, Junjie Liu, Peiyu Jia, Ning Qi, Zhiquan Chen, Shan Xu, Nanwen Li
Summary: This study investigates the effect of thermal treatment on the chain structure and gas transport performance of polyimide membranes. The results show that heating leads to the rearrangement of polyimide into rigid polybenzoxazole, increasing the size and quantity of free volume and enhancing gas permeability. Crosslinking during heating reduces the size and quantity of free volume by tightening the chain spacing. By designing the functional groups of the reaction monomer and applying appropriate thermal treatment, the microstructure of polyimide membranes can be adjusted to achieve high-performance gas separation.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Engineering, Chemical
Harsh D. Patel, Naveen K. Acharya
Summary: The thermal rearrangement and nanocomposite modification of HAB-6FDA polyimide membrane show significantly improved permeation properties for lighter gases, making it suitable for novel gas separation membranes.
POLYMER ENGINEERING AND SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Guoxiong Deng, Yilei Wang, Xueping Zong, Jiangzhou Luo, Xuezhen Wang, Chunxue Zhang, Song Xue
Summary: The study shows that esterification of binaphthol-based polyimide affects the pore structure and gas permeability of the derived carbon membranes.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2021)
Article
Engineering, Chemical
Li-Cheng Jheng, Jaesung Park, Hee Wook Yoon, Fang-Ching Chang
Summary: This study successfully enhanced the gas separation performance of mixed matrix membranes, especially in CO2-related separation, by controlling the morphology of the materials. It was found that adding UiO-66 metal-organic frameworks and co-continuous structures significantly increased the CO2 permeability of the mixed matrix membranes.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Yuxuan Zhao, Hongyan Wang, Xiangyun Liu, Xueping Zong, Jiangzhou Luo, Song Xue
Summary: Tailoring the micropore structure of 6FDA-based network PI membranes is crucial for achieving advanced gas separation performance. This study demonstrates the efficacy of incorporating carboxyl-containing functional units and inducing decarboxylation to enhance the micropore structure and gas transport properties of the membranes.
Article
Engineering, Chemical
Yunfei Yu, Xue Yang, Chenchen Zhang, Jie Chen, Wei Lin, Jianqiang Meng
Summary: This study reports an environmentally friendly and simple approach for preparing double-network (DN) ion gel membranes with high strength and excellent gas separation performance. By optimizing crosslinking density, mass ratio, and the type and content of free ionic liquid, the mechanical and gas separation properties of the DN membrane are improved.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Si-qi Jiang, Qiang Gao, Xi-guang Li, Chao-zhu Deng, Jun Qiu, Xiang-nan Zhu
Summary: A dual-strengthening pretreatment method is proposed to remove PVDF more efficiently and enhance the leaching of LiCoO2. Experimental results show that dual-strengthening pretreatment can effectively remove PVDF and significantly improve the leaching efficiency compared to single pretreatment methods.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Zengchi Hu, Xiaoyu Wang, Xiaohui Zhang, Xue Li, Jiangbin Xia
Summary: The rapid fabrication of high-performance composite membranes based on CMPs using simple and low-cost methods is challenging. In this study, three CMPs-based composite membranes were rapidly fabricated with adjustable size using unidirectional diffusion synthesis. The microstructural design enhanced the rejection rates of the membranes and they showed strong hydrolytic resistance, thermal stability, and acid-base resistance. Electrostatic adsorption and the adjustable microstructures significantly varied the repellence of the membranes to different charged molecules.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Farzaneh Rouhani, Matineh Ayedi, Nasser Safari
Summary: Introducing defects into porous metal-organic frameworks is important for improving their adsorption performance. Quasi-MOFs, an underutilized variant of large-scale, fundamentally deficient MOFs, have been found to have substantial amounts of unsaturated metal sites to offset the drawbacks of MOFs. In this study, a quasi-MOF was produced using a water-stable MOF and demonstrated significantly improved phosphate adsorption capability due to the presence of defect sites.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Valentin Reungoat, Morad Chadni, Louis M. M. Mouterde, Fanny Brunissen, Florent Allais, Helene Ducatel, Irina Ioannou
Summary: This study focuses on the recovery of sinapic acid using liquid-liquid extraction assisted by a hollow fiber membrane contactor from an aqueous feed obtained through the hydrolysis of mustard bran. The screening of solvents of different chemical nature showed that all tested solvents had an extraction efficiency of more than 80% for pH < 5. Four solvents were selected for use in the hollow fiber membrane contactor, and the volatile solvents showed higher mass transfer coefficients compared to non-volatile solvents. The extraction efficiency was intensified by increasing the initial concentration of sinapic acid and the feed-to-solvent ratio. CPME was found to have optimal recovery efficiency at a phase ratio of 8:1, yielding 0.9 g of sinapic acid per liter of CPME used.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Takahiro Sakamoto, Takafumi Hanada, Hayate Sato, Mayu Kamisono, Masahiro Goto
Summary: The emergence of the battery society has led to a high demand for battery metals, resulting in a strain on their supply. This study introduces a novel technique using a hydrophobic deep eutectic solvent (DES) for leaching and recovering battery metals from low-grade nickel laterite ores. The DES enables selective leaching and recovery of the metals, offering a promising pathway for the extraction of critical battery metals.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Rongrong He, Jiarui Chen, Chunyao Zhang, Dan Lu, Lin Zhang, Tao He
Summary: Researcher has developed a method to quantify the charge density in nanofiltration (NF) membrane separation layer and applied it in NF membranes that can separate Mg2+ and Li+. The results showed that overcompensated amine groups played a major role, and there was a linear relationship between charge density and coating bi-layers or PAH layers.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Zhijian Zhang, Min Chen, Zhe Lin, Zhichao Yang, Yafeng Du, Zhihui Chen, Zhenhao Yang, Kongyin Zhao, Ligang Lin
Summary: Membrane technology plays an important role in molecular/ion separation processes, but faces challenges such as membrane fouling. This study introduces a new ion-crosslinking method to fabricate copper alginate hydrogel membranes with improved mechanical strength and antimicrobial capabilities. The membranes exhibit excellent separation performance and enhanced long-term molecule/ion separation through improved anti-swelling properties. Molecular dynamics simulations and life cycle analysis highlight the pore structure and environmental friendliness of the hydrogel membranes. These findings provide valuable insights for developing sustainable hydrogel membranes with stable performance and high separation efficiency.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Dongmei Liu, Aiying Guo, Yanling Qi, Zhixin Ji, Hongjuan Li, Zhiwei Zhang, Xinyue Zhang, Kunze Wu, Aijun Cai
Summary: In this study, a stable magnetic Mg/Mn-layered double oxide-doped biochar composite (MgMnLDO-MBC) was prepared and successfully used for the removal of antibiotics and bacteria from wastewater. The composite exhibited enhanced surface areas, adsorption sites, and free radicals, leading to improved catalytic activity. The effects of different factors on the removal efficiency were evaluated, and the composite showed good reusability.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Feng Wang, Zhaoyong Bian, Yaru Zhang, Wenchao Yu, Qiang Zhang, Hui Wang
Summary: In this study, a nanofibrous layered structure of Ff-Ti3C2Tx-Co3O4 was prepared by self-assembling nanofibrous Co3O4 with lamellar fluorine-free MXene (Ff-Ti3C2Tx). The Ff-Ti3C2Tx-Co3O4 exhibited excellent catalytic activity for degradation, resistant to ionic interference, and maintained high removal efficiency of sulfamethoxazole (SMX) in municipal wastewater. The rapid SMX degradation involved fast electron transfer in redox cycles with PMS and the generation of 1O2 via PMS ->center dot O2 -> 1O2. This work provides new insights into antibiotic degradation mechanisms and electron transfer based on PMS activation.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Weipeng He, Jiacheng Luo, Yujie Wu, Tianhao Luo, Chen Tang
Summary: This study comparatively evaluated the role of cationic, anionic, and nonionic polyacrylamides (PAMs) in ballasted flocculation of clay suspensions under different aluminum sulfate (AS) coagulant dosages. The selection of PAMs and AS dosage had a significant influence on the size and shear resistance of ballasted floc aggregates.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Lixian Wang, Lizhi Zhao, Didi Si, Zhixin Li, Huiqin An, Hui Ye, Qingping Xin, Hong Li, Yuzhong Zhang
Summary: Metalloporphyrin-based nanozymes integrated with poly (vinylidene fluoride) membrane show high catalytic activity and reusability for the decolorization of Congo Red dye in continuous flow process.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Yongfei Ma, Chenyu Zeng, Yongzhen Ding, Jiayi Tang, Ondrej Masek, Zhikang Deng, Rui Mu, Zulin Zhang
Summary: In this study, sludge-derived biochar (SBC) was functionalized with various iron salts to enhance its adsorption ability for sulfamethoxazole (SMX) and magnetic collection performance. Ball milling was further employed to treat the optimal iron salt functionalized SBC (MSBC), resulting in ball milled SBC (BMSBC) with improved adsorption performance for SMX. The dominant driving mechanism for SMX adsorption onto BMSBC was confirmed to be multiple physicochemical forces, including 7C-7C conjugation, pore filling, H-bonding, Fe-O complexation, and electrostatic interactions. BMSBC exhibited favorable adsorption ability for SMX in actual waters and could be easily collected within 1 min due to its magnetic sensitivity.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Jinglin Tan, Xiaohui Mao, Wenjihao Hu, Hongbo Zeng
Summary: This study investigates the influence of PDMS chain architectures on surface properties and reveals that PDMS coatings with looped structures exhibit superior hydrophobicity, self-cleaning, and water sliding compared to coatings with linear structures. Additionally, both looped and linear PDMS coated stainless steel mesh/polyester fibers show efficient separation of oil/water mixture.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Engineering, Chemical
Wei-Liang Chen, Chih-Chia Cheng, Chien-Hsing Lu, Jem-Kun Chen
Summary: This study designs a novel sandwich-structured capacitor that reduces the absorption time of pollutants using dielectrophoresis force. By coating graphene oxide on polystyrene microspheres as adsorbents and encapsulating them within the capacitor, the adsorption rate is significantly enhanced. Additionally, frequency manipulation allows for the recycling of adsorbents and concentration of dyes, minimizing secondary pollution.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)