JOURNAL OF APPLIED POLYMER SCIENCE
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2023
·Vol. 141
·期 2
·e54792
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IF 3
Qian Chen,Dayong Ren,Weichen Sheng,Kan Zhang
Two novel bio-based benzoxazine monomers containing imide or amide group (HPIDD-fa and HPBA-fa) were synthesized from raw materials of benzoyl chloride/phthalic anhydride, tyramine, furfurylamine and paraformaldehyde via a two-step reaction. Fourier transform infrared spectroscopy (FT-IR), proton and carbon nuclear magnetic resonance (NMR) spectroscopies were performed to characterize the structures of the benzoxazine monomers. The curing behavior was investigated by using differential scanning calorimetry (DSC) and in situ FT-IR, and the DSC results indicate that the peak curing temperatures of HPIDD-fa and HPBA-fa are centered at 248.5 and 230.1°C, respectively. In addition, thermogravimetric analysis (TGA) suggests that the newly developed bio-based benzoxazine-derived polybenzoxazines present excellent thermal stability with T d10 (temperature at 10% weight loss) of 385 and 368°C for poly(HPIDD-fa) and poly(HPBA-fa), respectively. The current investigation suggests that our newly obtained bio-based thermosetting resins are promising materials for high-tech applications.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Yang Li,Dario R. Dekel,Xuezhong He
Amine-rich facilitated transport membranes (FTMs) attract great interest in intensifying the membrane-based CO 2 separation processes. The high-molecular-weight polyvinylamine (PVAm) polymers containing fixed-site carriers of the amino groups were used to prepare highly CO 2 -permeable membranes. The sterically hindered PVAm polymers of poly(N-methyl-N-vinylamine) and poly(N-isopropyl-N-vinylamine) were obtained by functionalization of PVAm to provide superior CO 2 solubility. By loading the mobile carriers of amino acid salt (AAS) and CO 2 -philic graphene oxide (GO), the prepared FTMs render enhanced CO 2 permeance and CO 2 /N 2 selectivity. The d-spacing of 8.8 Å and the ultramicropores of 3.5 Å from GO nanosheets provide the combination of both selective surface flow and molecular sieving mechanisms to achieve improved CO 2 permeance and CO 2 /N 2 selectivity. In addition, the intercalation of GO hinders N 2 transport through the membrane due to a longer pathway, while the mobile carriers of AAS introduced into the PVAm matrix facilitate CO 2 transport through the selective layer. Therefore, the CO 2 /N 2 selectivity of the prepared FTMs was significantly enhanced to 171 based on the intensified carrier-driving transport mechanism. It can be concluded that amine-rich membranes based on both fixed and mobile carriers of the amino groups together with intercalated GO can synergistically improve the CO 2 /N 2 separation performance, and be potentially applied for CO 2 capture from flue gas .
研究领域:
化学工程
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材料科学
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环境科学
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产品关联
DOI
高影响因子
Chinese Journal of Natural Medicines
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2020
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IF 2.014
Yong-Jiang WANG,Li WANG,Xin HE,Dong-Dong XU,Jun TANG,Ya-Tuan MA,Yi-Jun YAN,Yu-Cheng GU,Jing YANG,Sheng-Xiong HUANG
Inthomycins are polyketide antibiotics which contain a terminal carboxamide group and a triene chain. Inthomycin B ( 1 ) and its two new analogues 2 and 3 were isolated from the crude extract of Streptomyces pactum L8. Identification of the gene cluster for inthomycin biosynthesis as well as the 15 N -labeled glycine incorporation into inthomycins are described. Combined with the gene deletion of the rare P450 domain in the NRPS module, a formation mechanism of carboxamide moiety in inthomycins was proposed via an oxidative release of the assembly chain assisted by the P450 domain.
研究领域:
微生物学
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生物化学
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产品关联
DOI
PubMed
高影响因子
ACS ES&T Engineering
·
2023
·
IF 7.1
Du Chen,Jianheng Hong,Lanjing Liu,Ningyi Chen,Bingjun Pan
Simultaneous sequestration and reduction of bichromate [Cr(VI)] poses an attractive and practical fashion for treating Cr(VI)-contaminated wastewater, for it not only immobilizes the pollutant but also reduces its toxicity. To this end, an EDA-functionalized adsorbent (EDA@CMPS) was developed with a simple one-step method by integrating ethylenediamine (EDA, a reversible redox unit) onto the skeleton of chloromethylated polystyrene adsorbent (CMPS), and it can sequestrate Cr(VI) and in situ reduce Cr(VI) to Cr(III), which was then immediately locked inside the adsorbent phase. Batch experiments confirmed that EDA@CMPS had a high removal capacity toward Cr(VI) (419 mg/g, at 25 °C), a large proportion of which was reduced to Cr(III) without leaking into the aqueous phase at pH ≥ 2. Ubiquitous anions (Cl–, NO3–, SO42–, and H2PO4–) and cations (Mg2+ and Ca2+) have a certain effect on the removal efficiencies, but EDA@CMPS still demonstrated satisfied Cr(VI) removal even with the competing ions at 100-times higher concentration. FT-IR and XPS analyses revealed that the amine group of EDA was responsible for sequestrating and reducing Cr(VI), where the amine group was oxidized into an imine group, which then played a key role in immobilizing the generated Cr(III) via chelation. Attractively, even under neutral conditions, EDA@CMPS also demonstrated decent removal and reduction performance toward Cr(VI). Furthermore, the yielded imine group can be perfectly restored to an amine group by simple alkali-acid treatment. Repeated removal–regeneration cycles verified the reusability of EDA@CMPS in treating Cr(VI) solution. Fixed-bed column experiments and treatment of a real electroplating wastewater further validated the potential of EDA@CMPS in treating Cr(VI) wastewater for practical application.
研究领域:
环境科学
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化学工程
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水处理
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DOI
高影响因子
CELLULOSE
·
2024
·Vol. 31
·期 10
·6141-6153
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IF 4.9
Song Jun,Wang Linfeng,Shan Jicheng,Li Chuanmeng,Wang Mengdie
Cellulose liquid crystal solutions have been extensively studied, and the methylene length of mesogenic units has a significant influence on the properties of cellulose liquid crystal solutions. In this study, 4-(ω-(methylimidazole)alkyloxy)-4’-(cyano)-biphenyl (CBP-n) with 4–7 methylene lengths were synthesized as mesogenic units to prepare cellulose side chain liquid crystal in 1-Allyl-3-methylimidazolium chloride (AMIMCl). And their liquid crystal properties were studied by differential scanning calorimetry (DSC), in-situ infrared spectrometer (IR), torque rheometer, and polarizing microscope (POM). The results showed that CBP-n with 4–7 methylene lengths were thermotropic liquid crystal, and the cellulose/CBP-n/AMIMCl solutions were lyotropic liquid crystal when the concentration of cellulose is 6wt% and the concentration of CBP-n with methylene length 4 and 6 is 3wt%. In-situ IR proved that the liquid crystal formation of cellulose/CBP-n/AMIMCl solution was caused by the hydrogen bonding formed between cellulose and CBP-n. And the solutions have a fewer entanglement number and lower viscosity than those of methylene length 5 and 7, indicating that the hydrogen bonding interaction between CBP-n with even methylene length and cellulose molecule is stronger than that of odd methylene length. This study provides a new approach to produce cellulose fibers using cellulose/CBP-n/AMIMCl as a new renewable resource.
研究领域:
材料科学
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化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Yilei Fang,Mengyu Tang,Xu Wu,Jiajie Zhang,Qian Guan,Yinzhou Luo,Xin Yu,Ranwen Ou
Trace amount of Cr(VI) in water still threatens human health and ecology. Several reported amine-based adsorbents can remove trace Cr(VI) in acidic solutions of pH 2–5, but perform badly at neutral and alkaline conditions, which is insufficient for treating natural waters. Also, the chemical eluate leads to secondary pollution. Here, the amine-rich thermo-responsive poly(dimethylaminoethyl methacrylate) (pDMAEMA) was selected based on its high pK a value and introduced into MOFs to produce pDMAEMA-DUT-5 for effective removal of trace Cr(VI) from natural waters. The composite with a polymer loading of 23.4 wt% achieved the highest adsorption capacity of 182.2 mg g −1 under an optimized condition, that is, at pH 3 and 25 °C. Besides, this material effectively reduced trace Cr(VI) content in natural waters from 100 to 1 μg L −1 by one filtration in a column. Its high selectivity was verified and further confirmed by the strong adsorption energy of Cr(VI) and −N(CH 3 ) 2 . Furthermore, the composite could be fully regenerated in 45 °C water within 10 min, concentrating Cr(VI) for 270 folds in one adsorption–desorption cycle and maintaining over 99 % performance after five cycles. It demonstrated excellent removal efficiency, high selectivity, and thermal regeneration stability. This work presents a simple strategy to design highly selective and reusable ion adsorbents for effective and sustainable removal or recovery of toxic and precious ions, while its thermal regeneration function largely simplifies further treatments.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Cong Jiang,Maohong Fan,Ge Gao,Wufeng Jiang,Xiaoshan Li,Cong Luo,Liqi Zhang,Fan Wu
In order to alleviate the intensive energy demand of amine-based post-combustion carbon capture technology, metal oxyhydroxide AlOOH of nanoscale was synthesized through the hydrothermal method and applied to accelerate the CO 2 desorption rate and reduce the regeneration heat duty of aqueous monoethanolamine (MEA) solution for the first time. Results showed that the use of AlOOH could accelerate the desorption rate by up to 560% and increase the desorption amount by 251%. By comparing the performance between AlOOH and Al 2 O 3 , it can be found that the presence of extra hydroxyl groups is 20.6% more efficient in catalyzing CO 2 desorption. According to a simplified heat transfer model created in this work, AlOOH could reduce the heat duty by 17% with only 0.1 wt% loading, which exhibited the highest performance cost ratio among related literature. In addition, the cyclic stability of AlOOH was confirmed through various characterization methods, including XRD, FT-IR, SEM, and N 2 adsorption–desorption. More importantly, a possible catalytic mechanism of AlOOH was discussed and proved where it could change reaction pathways in different CO 2 loading regions. This work reveals a promising research direction towards cost-efficient and high-performance metal oxyhydroxide catalysts in the catalytic amine regeneration field to approach the net-zero carbon emission goal.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2023
·Vol. 69
·期 5
·e18023
·
IF 3.7
Qing Sun,Yan Dong,Shuai Wang,Zhanfang Cao,Xin Ma,Hong Zhong
Modified surfactants can regulate their adsorption at the target surface and are essential for various separation applications such as froth flotation. Thioether-containing hydroxamic acid (BTHA) is an excellent oxidized-ore collector with poor dispersibility. Herein, acylamino, which possesses the ability to improve the surfactants' self-assembly and dispersion, was introduced to synthesize N-[6-(hydroxyamino)-6-oxohexyl] benzylthioacetamide (BTAHA); thus, applying it to cassiterite flotation. Surface tension, adsorption capacity, in situ AFM, and surface energy results reveal BTAHA displays strong bubble stability and readily adsorbs onto the mineral's surface, promoting hydrophobic flotation. BTAHA is an effective cassiterite collector and has good separation effects on cassiterite against calcite. It can form Van der Waals forces and five-membered hydroxamate-(O,O)-Sn rings with Sn atoms on cassiterite surfaces via thioether and hydroxamate groups. Meanwhile, the presence of intermolecular hydrogen bond between the amide groups facilitates the self-assembly of the collectors on the cassiterite surface, and has broad industrial application prospects in various separation processes.
研究领域:
矿物加工工程
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界面化学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Evans Dovi,Aaron Albert Aryee,Alexander Nti Kani,Farid Mzee Mpatani,Jianjun Li,Zhaohui Li,Lingbo Qu,Runping Han
Several pollutants found in industrial wastewater , such as Congo red dyes (CR), have been shown to be toxic to organisms. To protect human health and the environment, industrial effluents must be purified before being released into bodies of water. In order to effectively remove CR from the solution, amino functionalized walnut shells (WNS) were synthesized. Batch and fixed-bed column systems were used in this research. The Langmuir isotherm model fits the experimental findings well in these two systems, whereas the pseudo-second-order and Thomas kinetic models characterize batch and column CR adsorption, respectively. The adsorption capacity of ACWNS toward CR was to 224.4 mg g −1 at 303 K from Langmuir model. Electrostatic interactions and hydrogen bonding may be the mechanisms. The column research showed that adsorption was more favorable at low inlet solution concentration, low flow rate, or high column depth. The column mass transfer capacity parameter (B) increased with increasing concentration (0.461, 1.59, and 2.47 for 50, 100, and 150 mg L −1 , respectively) owing to a greater driving force for CR adsorption onto ACWNS, while adsorbate–adsorbent affinity (β) exhibited a reverse trend. The regeneration property of CR-loaded ACWNS was excellent using NaOH solution. The thermodynamic study revealed that CR removal was both spontaneous and endothermic. ACWNS is promising to remove CR from the solution.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Yizhou Feng,Daohui Lin,Kun Yang,Wenhao Wu
Knowledge of antibiotic desorption from high-temperature biochar is essential for assessing their environmental risks, and for the successful application of biochar to remove antibiotics. In previous studies, irreversible pore deformation, formation of charge-assisted hydrogen bonds or amide bonds were individually proposed to explain the desorption hysteresis of antibiotics on biochars, leading to a debate on hysteresis mechanism. In this study, desorption of sulfamethoxazole (SMX), ciprofloxacin (CFX) and tetracycline (TET) on a wood chip biochar produced at 700 °C (WBC700) and its oxidized product (O-WBC700) was investigated to explore the underlying hysteresis mechanism. Significant desorption hysteresis was observed for SMX, CFX and TET on WBC700 and O-WBC700. Hysteresis index (HI) of each antibiotic was higher on O-WBC700 with more oxygen-containing groups than WBC700, and was higher at lower equilibrium concentration. HI of antibiotics on WBC700 (or O-WBC700) increased in the order of SMX < CFX < TET. The calculated adsorption enthalpy of each antibiotic on WBC700 was positive, indicating an endothermic process. These phenomena together with FTIR, XPS spectra confirmed that the desorption hysteresis mechanism of antibiotics on high-temperature biochar is the formation of amide bonds by amidation reaction, but not the pore deformation or the hydrogen bond. Moreover, antibiotic can form amide bonds with WBC700 only if the amine group with p K a > 4.0, and the HI values were positively correlated with their p K a values. Amine group of antibiotics with higher p K a value show more nucleophilicity and could form stronger amide bonds with carboxyl group of biochar. The obtained results could help to solve the debate on desorption hysteresis mechanism of antibiotics on high-temperature biochars, and provide a new insight into the role of amine groups and amidation reaction on the hysteresis.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
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IF 4.321
Bin Jiang,Huawei Yang,Luhong Zhang,Rongya Zhang,Yongli Sun,Yong Huang
A series of Brønsted acidic ionic liquids having a protonated amide- or lactam-based cation were synthesized and investigated as extractants and catalysts in the extraction combined with oxidative desulfurization (ECODS) of both model oil and diesel fuel, with hydrogen peroxide (H 2 O 2 , 30 wt%) as oxidant. Each of them showed obvious removal of benzothiophene (BT) and dibenzothiophene (DBT) in model oil. Among them, [HCPL][TFA] exhibited the best performance by completely removing BT and DBT in a short time. The detailed structure and conformation of [HCPL][TFA] were investigated by 1 H NMR and FTIR as well as theoretical calculation. HCPL + cation was verified to exist in an enol form, which was supposed to contribute to high desulfurization performance by improving the formation of peroxides. In the end, two kinds of diesel were used to evaluate its desulfurization performance. [HCPL][TFA] can reduce the S-content of real hydrogenated diesel from 659.7 ppm to 8.62 ppm with 98.69% S-removal efficiency after two ECODS processes. Furthermore, the total S-content of straight-run diesel fuel was reduced to 89.36 ppm from 11,034 ppm with a similar S-removal rate. The results of GC-PFPD before and after each ECODS process indicated that almost all the original S-compounds in diesel had been converted to their corresponding oxidation products. The desulfurization performance was actually restricted by extraction capability.
研究领域:
化学工程
·
能源科学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2018
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IF 3.024
Na Rao,Mei Wang,Ziming Shang,Yanwen Hou,Guozhi Fan,Jianfen Li
Modifications by impregnation and grafting are commonly used for the preparation of amine-functionalized MCM-41. A comprehensive evaluation of the advantages and disadvantages of the two methods was performed in this work. MCM-41 was synthesized by the hydrothermal method, setting the amine-loading mass fraction at 40, 50, and 60 wt %. Three amine-modified adsorbents were prepared by impregnating polyethylenimine (PEI), and the three other adsorbents were prepared by grafting 3-aminopropyltriethoxysilane (APTS) onto MCM-41. The as-prepared adsorbents were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and N2 adsorption–desorption techniques. CO2 adsorption capacities were measured, and the experimental data were fitted with adsorption kinetic models. The cyclic stability of the adsorbents prepared by the two kinds of amine-modified methods was compared using the cyclic adsorption–desorption experiments. The characterization results showed that the target adsorbents were prepared successfully. The thermal stability of the adsorbents modified by grafting was better than the thermal stability of the adsorbents modified by the impregnation. Maximum CO2 adsorption capacities of 3.53 mmol g–1 (50% PEI–MCM-41) and 2.41 mmol g–1 (50% APTS–MCM-41) could be reached at 25 °C and 1 atm, which were 4.7 and 3.2 times greater than that of MCM-41. The Avrami model fitted the experimental data well, indicating a variety of interactions between the adsorbents and CO2. CO2 adsorption capacity after 5 adsorption–desorption cycles decreased by 14.22 and 5.19% for the adsorbents prepared by impregnation and grafting, respectively. It was concluded that MCM-41 modified by impregnation and grafting followed the same kinetic model. The absorbents modified by impregnation showed higher CO2 adsorption capacity and amine-loading efficiency, while those prepared by grafting had better thermal and cyclic stabilities.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）