DESALINATION
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2023
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IF 9.9
Kaiming Fan,Chunwen Pan,Yanling Liu,Xu Yuan,Xiaoping Wang,Yidi Huang,Peng Cheng,Shengji Xia
Due to the relatively low reactivity of hydroxyls with acyl chloride groups, the synthesized polyester (PE) membranes commonly have loose structures, only capable of removing large-molecule organics with low rejection of inorganic salts. In this study, the pore size reduction of the synthesized PE membrane was successfully achieved by optimizing the interfacial polymerization (IP) reaction between erythritol and trimesoyl chloride (TMC). The optimized membrane was able to maintain a high xylose rejection (∼60 %) and acceptable water permeance (7.85 L m −2 h −1 bar −1 ), which was suitable for drinking water treatment . Through comprehensive characterizations, a two-stage membrane formation process was demonstrated regarding the reaction between aqueous monomers with different reactive functional groups and TMC. The highly reactive primary hydroxyls more preferentially participated in the initial reaction stage, leading to a linear cross-linking pattern of polyester. When the molecular diffusion was inhibited, the participation of secondary hydroxyls made the reaction proceed toward partial or full cross-linking. The distinct roles of the two kinds of hydroxyl groups were further verified by the energy barrier differences obtained by density functional theory (DFT) calculation. The exploration of membrane-optimized preparation and formation mechanisms can promote the structural regulation and tailored synthesis of PE membranes for various applications.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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2023
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IF 9.5
Hanzhen Peng,Langlang Chen,Yifeng Wang,Bokai Cao,De Li,Yong Chen
As a graphite-like material, the LiBC can deliver a high capacity up to 500 mA h g–1 in Li-ion batteries, which is dependent on the carbon precursor, the high-temperature treatment, and the lithium insufficiency. However, the underlying mechanism is still not clear for the electrochemical reactions of LiBC. In this work, the pristine LiBC was reacted with aqueous solutions of different alkalinity, which was delithiated chemically and retained the layered structure. According to the XPS and NMR results, the B–B bond might be produced through the aqueous reaction or the initial charge process, which can be oxidized (charged) and reduced (discharged) in the electrochemical measurements. In the Li-ion battery, the reversible capacity of LiBC increases evidently with the alkalinity of aqueous solution and significantly rises to a similar value of ca. 285 mA h g–1 under 200 cycles. Therefore, the specific capacity of LiBC should be contributed by the active sites of B–B bonds, which can be significantly increased through the reaction with the hydroxyl ions, and this strategy might be adopted to activate more graphite-like materials.
研究领域:
材料科学
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电化学
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电池技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION
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2013
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IF 1.233
Shunping Wang,Xiaodeng Yang,Qingquan Bai,Tianduo Li
A number of tertiary amines and organotin catalysts for the phenyl isocyanate- 1,2-propylene glycol reaction were investigated by using in situ FT-IR. The reaction rate of each hydroxyl group, which is defined as the ratio between the rate constant of the secondary hydroxyl group and the rate constant of the primary hydroxyl group, is described with a second-order equation. The influence of different catalyst concentrations as well as the reaction temperature is discussed. It is observed that the selectivity depends on temperature but not on concentration, and stannous octoate is the most effective catalyst. The thermodynamic parameters were determined for the catalyzed reactions, primary and secondary hydroxyl groups being differentiated.
研究领域:
化学工程
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材料科学
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催化化学
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
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2021
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IF 6.024
Xiangchen Kong,Chao Liu,Baolong Wang,Weicong Xu,Yuyang Fan,Ming Li,Rui Xiao
A complex copper acid catalyst (SA-Cu/CuMgAlOx) was developed with boosted catalytic activity for the hydrodeoxygenation (HDO) of lignin-derived phenolics. Remarkably, the yields of total monomers and cyclohexanes from the HDO of lignin pyrolysis bio-oil were significantly improved after the catalyst modification with salicylic acid, which increased by 17 and 40%, respectively, at 300 °C for 8 h. The catalyst characterizations revealed that acidic oxygen-containing functional groups (−OH and −COOH) were introduced onto the catalyst surface without corrosion to the metallic framework. The acidic groups contributed to the formation of surface Brønsted acid sites, which participated in the hydrogenolysis and dehydroxylation reactions of the phenolics in bio-oil. The catalyst was deactivated after four cycles of bio-oil HDO and could be recovered after the removal of carbon deposits and the reactivation of Cu species. The results offered appealing opportunities for tailoring more efficient copper-containing catalysts for the HDO of lignin-based phenolics.
研究领域:
化学工程
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催化
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可再生能源
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）