MOLECULES
·
2023
·Vol. 28
·期 6
·2444
·
IF 4.6
Yan Wang,Peng Dou,Xiaofeng You,Qing Liu,Zhaoyang Fei,Xian Chen,Zhuxiu Zhang,Jihai Tang,Mifen Cui,Xu Qiao
Resins have enormous potential in the removal of naphthenic acids (NAs) from transformer oil due to their rich porosity and high mechanical and diversified functionality, whereas their poor adsorption capacity limits application. In this work, the polystyrene–diethylamine resin (PS−DEA−x) was prepared by grafting diethylamine (DEA) onto chloromethylated polystyrene (PS−Cl) resin to efficiently adsorb cyclopentane carboxylic acid from transformer oil for the first time. The characterization analysis results indicated that amine contents were significantly enhanced with the increase in DEA. Particularly, resin with a molar ratio of 1:5 depending on chloromethyl to DEA (PS−DEA−5) exhibited the highest amine contents and efficient adsorption of cyclopentane carboxylic acid (static adsorption capacity up to 110.0 mg/g), which was about 5 times higher than that of the pristine PS−Cl. The thermodynamic and kinetic studies showed that the adsorption behaviors could be well fitted to the Langmuir isotherm equation and pseudo−second−order rate equation. Moreover, it was found that 1 g of the PS−DEA−5 can decontaminate about 760 mL transformer oil to meet reuse standards by a continuous stream, indicating its potential application in industry.Keywords:resin;diethylamine;chemical modification;cyclopentane carboxylic acid;transformer oil purification
研究领域:
化学工程
·
材料科学
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产品关联
DOI
PubMed
高影响因子
Carbon Letters
·
2024
·Vol. 34
·期 7
·1927-1939
·
IF 5.5
Ma Liyan,Sun Fengyi,Jiang Zhuwu,Di Hongcheng,Pan Chuntao,Zhang Fengying,Bai Xue,Zhang Hongyu
Activated carbon has broad application prospects for treating pollutants due to its easy availability, low cost and good adsorption. In our work, nano-activated carbons (NAC) with abundant functional groups are obtained by the oxidation modification of HNO 3 , (NH 4 ) 2 S 2 O 8 , and KMnO 4 , which are used to construct the particle electrodes to degrade NDEA in a continuous flow electrochemical reactor, and the influence of relevant factors on the performance of NDEA removal is discussed. The experimental data show that the optimal degradation efficiency is 42.55% at the conditions of 3 mL/min influent water flow, 0.21 M electrolyte concentration, 10 mA/cm 2 current density, and 10 μg/mL initial NDEA concentration. The degradation of NDEA conforms to a quasi second order kinetic equation. The electrocatalytic mechanism of NAC electrodes for removing NDEA is firstly discussed. The effects of different free radicals on the degradation of NDEA are also demonstrated through free radical quenching experiments, indicating that the degradation of NDEA is dominated by ⋅OH. The degradation pathway of NDEA and final products are obtained using GC–MS. NAC particle electrodes as the cheap and efficient electrocatalyst in continuous flow electrochemical reactor system provide a greener solution for the removal of disinfection by-products from drinking water.
研究领域:
环境科学
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电化学工程
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DOI
高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 19
·2189-2195
·
IF 2.896
Lu Li,Jingru Li,Tiantian Meng,Zhanfang Liu,Hong Zhou,Jun Zhu,Junqing Shi
In this study, based on silica hollow sphere photonic crystals (SHSPCs), a simple and selective fluorescence sensor for high-performance diethylamine detection was developed. The sensor does not involve complicated integration of arrays or tedious synthetic work. During the detection, the SHSPCs could significantly enhance the fluorescence intensity of rhodamine 6G (Rh6G), and meanwhile, adsorb some Rh6G on their surface. Due to the competitive adsorption, diethylamine could free the Rh6G which was adsorbed on the surface of the SHSPCs, thus enhancing the fluorescence emission intensity with the increase of Rh6G concentration. The second enhancement of the fluorescence emission enabled the selective detection of diethylamine. It is remarkable that a simple and readily available dye (Rh6G) facilitates the efficient detection of diethylamine. Moreover, the sensor has good interference immunity, stability and reusability.
研究领域:
材料科学
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分析化学
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DOI
高影响因子
POLYMER BULLETIN
·
2016
·Vol. 74
·期 3
·625-639
·
IF 1.371
Zhang Jinglin,Liu Huidi,Liu Hongxi,Hu Jian,Tan Shaozao,Wu Ting
Abstract A composite anion exchange membrane of crosslinked quaternized polyepichlorohydrin/polytetrafluoroethylene (CQPECH/PTFE) had been prepared via a green and facile method, where diethylamine, 1-methylimidazole and PTFE, respectively, served as crosslinking agent, quaternization reagent and supporting material. The structure and morphology of CQPECH/PTFE membrane were investigated. Water uptake, swelling ratio, ionic exchange capacity, hydroxide conductivity, chemical stability, and thermal and mechanical properties were measured to evaluate its performance in a direct methanol alkaline fuel cell. The results indicated that CQPECH had penetrated into the pores of PTFE membrane, showing a dense and uniform structure without any pore and phase separation. Besides, CQPECH/PTFE membrane exhibited high ionic conductivity, considerable ionic exchange capacity, moderate water uptake and low swelling ratio. More importantly, the obtained composite membrane displayed high tensile strength and good chemical and thermal stability, suggesting the great potential application of CQPECH/PTFE membrane as anion exchange membrane. Graphical abstract Crosslinked quaternized polyepichlorohydrin/polytetrafluoroethylene composite anion exchange membrane had been prepared via a green and facile method, where diethylamine served as crosslinking agent. With a dense and uniform structure without any pore and phase separation, the obtained composite membrane exhibited high tensile strength and good chemical stability.
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
NANOTECHNOLOGY
·
2018
·Vol. 29
·期 7
·075708
·
IF 3.404
Hengcong Tao,Jingjing Ding,Chao Xie,Yunnan Gao,Jinliang Song,Zhenyu Sun
We demonstrate a facile and versatile method to grow Ru particles uniformly on pristine few-layer graphene (FLG) in supercritical diethylamine. In particular, a large number of Ru subnanometer clusters less than 1.0 nm were observed. The particle size can be tuned by manipulating the loading content of Ru and controlling the reaction temperature. The resulting Ru/FLG showed remarkably high activity, selectivity, and reusability towards the hydrogenation of levulinic acid to γ-valerolactone. This method is flexible, and can be extended to the synthesis of a variety of other ultrafine metal particles supported on FLG.
研究领域:
材料科学
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催化化学
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绿色化学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Ning Yao,Jinfeng Chen,Ren Feng,Zhipeng Liu,Yu He,Zhuwu Jiang
N -nitrosodiethylamine (NDEA) is a disinfection by-product (DBP) and is classified as a probable carcinogen by the International Agency for Research on Cancer. Its concentration is lower but its toxicity is higher than other DBPs. Designing a new adsorbent with a high adsorption effect on low concentrations of NDEA instead of traditional materials will be useful. To the best of our knowledge, this is the first study to investigate metal-organic frameworks (MOFs) for the adsorption of NDEA. Two novel Al-based MOFs were synthesized by modifying MIL-96 with amino and thiol groups. Their adsorption performances at low concentrations of NDEA in water were compared using adsorption kinetics and isotherm models. It was observed that MIL-96 modified with thiol groups (MIL-96-M) followed the Langmuir and pseudo-second-order models and exhibited the best adsorption performance. Owing to the well-matched pore size and hydrophobicity, the Langmuir adsorption capacity of MIL-96-M for NDEA was achieved at 1004.71 μg/g. The parameters of the adsorption performance were investigated using the Box-Behnken response surface methodology, and on the basis of which, the performance under different conditions was predicted. The experimental data suggested that the increase in temperature and time was beneficial for the adsorption performance, whereas an increase in dosage was not beneficial. It was identified that the adsorption mechanism between MIL-96-M and NDEA involves van der Waals forces, electrostatic interactions, and nucleophilic reactions by characterization and density functional theory (DFT).
研究领域:
环境科学
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材料科学
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毒理学
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产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Lin-Cong He,Hua-Hui Xu,Xing-Yue Leng,Ling-Yun Jin,Ai-Ping Jia,Meng-Fei Luo,Jian Chen
Selective catalytic oxidation of nitrogen containing volatile organic compounds (NVOCs) is very meaningful but still remains big challenge because it is very difficult to balance the oxidation activity and N 2 selectivity of available catalysts. In order to develop excellent catalysts with high N 2 selectivity in wide temperature window ( △T ) during NVOCs oxidation, CeO 2 modified CuO/ZSM-5 catalysts with different CeO 2 addition order were prepared for diethylamine (DEA) oxidation. Detailed characterizations of catalysts such as XRD, XPS, H 2 -TPR and NH 3 -TPD were conducted, it is found that addition of CeO 2 obviously changes the geometrical and electronic states of CuO active sites in the catalyst, and CeO 2 addition order affects the Ce 3+ ratio on the catalyst surface. Promotion of CeO 2 species enables the generation of more highly active Cu species (Cu + species and finely dispersed CuO clusters) for DEA oxidation; and synergistic catalysis of the Ce 3+ species, active Cu species and acid sites in ZSM-5 leads to the high N 2 selectivity in wide temperature window ( △T ). Compared to the CeO 2 /CuO/ZSM-5 and CuO-CeO 2 /ZSM-5 catalysts, the CuO/CeO 2 /ZSM-5 catalyst exhibits moderate high oxidation activity with T 99 of 230 °C and the widest △T of 150 °C for high N 2 selectivity. Our primary results in this work provide the efficient strategy for improving catalyst employed for NVOCs selective oxidation.
研究领域:
催化化学
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环境科学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Ling Zhou,Yaoyu Zhang,Yue Liu,Zhongbiao Wu
This work investigated the reaction behaviors of diethylamine (DEA) catalytic oxidation on various Cu-based catalysts with different supports (TiO 2 , HZSM-5(27), HZSM-5(130) and S-1). It was found that the acidic environment of catalysts greatly influenced reaction pathways of DEA oxidation. On Cu 5 /TiO 2 catalyst mainly with Lewis acidity, DEA preferentially dissociated through a two-step dehydrogenation to produce acetonitrile and ethylene, while on Cu 5 /HZSM-5(27) catalyst with strong Brønsted acidity, DEA could directly decompose into ethylamine and ethylene via N-C cleavage. Both pathways existed simultaneously over Cu 5 /HZSM-5(130) with decreased Brønsted acidity. Thereafter, acetonitrile could be further oxidized on the Cu 5 /TiO 2 catalyst to generate a large amount of NO x via NCO(a) intermediates over-oxidation, while ethylamine on Cu 5 /HZSM-5 samples would convert to acetamide and then produced N 2 and CO 2 . The Cu 2+ species due to enriched Brønsted acid sites in Cu 5 /HZSM-5 catalysts ensured excellent N 2 selectivity via internal SCR mechanism. Additionally, the strong Brønsted acidity of Cu 5 /HZSM-5(27) could induce the polymerization of carbonaceous intermediates and thereby resulted in severe coke deposition. As for Cu 5 /HZSM-5(130) and Cu 5 /S-1 with relatively lower Brønsted acidity and reducibility would release some unwanted gas-phase by-products like ethyl-isocyanate. This work provided useful guidance for designing NVOCs catalysts with high activity and less toxic by-products.
研究领域:
催化化学
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环境科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2022
·
IF 5.723
Lin-Cong He,Xu-Fang Wang,Chu-Feng Liu,Bei Li,Meng-Fei Luo,Jian Chen
An efficient MnO x /CeO 2 /ZSM-5 catalyst was developed for selective oxidation of diethylamine (DEA) with high N 2 selectivity in a wide temperature window ( Δ T = 140 °C), owing to the existence of oxidation and selective catalytic reduction (SCR) active sites. MnO x species prefer to locate on the surface of CeO 2 compared to ZSM-5, and the presence of CeO 2 is beneficial to form more Mn 4+ species, the active sites for oxidation reaction. The mechanistic investigation suggests that internal SCR of NO x generated from the over-oxidized DEA is the crucial pathway for N 2 generation. The high SCR activity of the MnO x /CeO 2 /ZSM-5 catalyst in oxidation conditions is mainly attributed to the synergistic catalysis of Mn 4+ species and acid sites of ZSM-5, the active sites for SCR reaction. Thus, it has been clearly clarified that addition of CeO 2 and its addition sequence could modulate the surface active sites of MnO x /ZSM-5 catalyst for the selective catalytic oxidation of DEA.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2013
·
IF 2.112
Xiaolei Qian,Hua Fan,Chaozhan Wang,Yinmao Wei
Ion-exchange membrane is of importance for the development of membrane chromatography. In this work, a high-capacity anion-exchange membrane was prepared by grafting of glycidyl methacrylate (GMA) onto the surface of regenerated cellulose (RC) membranes via surface-initiated atom transfer radical polymerization (SI-ATRP) and subsequent derivatization with diethylamine. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to characterize changes in the chemical functionality, surface topography and pore morphology of the modified membranes. The static capacity of the prepared anion-exchange membrane was evaluated with bovine serum albumin (BSA) as a model protein. The results indicated that the anion-exchange membrane which could reach a maximum capacity of 96 mg/mL for static adsorption possesses a higher adsorption capacity, and the adsorption capacity increases with the polymerization time. The effect of pH and salt concentration confirmed that the adsorption of BSA followed ion-exchange mechanism. The established method would have potential application in the preparation of anion-exchange membrane.
研究领域:
生物化学
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材料科学
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产品关联
DOI
高影响因子
PeerJ
·
2024
·
IF 2.3
Yaxin Wang,Li-ming Zhao,Naijie Feng,Dianfeng Zheng,Xue Feng Shen,Hang Zhou,Wenxin Jiang,Youwei Du,Huimin Zhao,Xutong Lu,Peng Deng
The aim of this experiment was to investigate the effects of exogenous sprays of 5-aminolevulinic acid (5-ALA) and 2-Diethylaminoethyl hexanoate (DTA-6) on the growth and salt tolerance of rice ( Oryza sativa L.) seedlings. This study was conducted in a solar greenhouse at Guangdong Ocean University, where ‘Huanghuazhan’ was selected as the test material, and 40 mg/L 5-ALA and 30 mg/L DTA-6 were applied as foliar sprays at the three-leaf-one-heart stage of rice, followed by treatment with 0.3% NaCl (W/W) 24 h later. A total of six treatments were set up as follows: (1) CK: control, (2) A: 40 mg⋅ L −1 5-ALA, (3) D: 30 mg⋅ L −1 DTA-6, (4) S: 0.3% NaCl, (5) AS: 40 mg⋅ L −1 5-ALA + 0.3% NaCl, and (6) DS: 30 mg⋅ L −1 DTA-6+0.3% NaCl. Samples were taken at 1, 4, 7, 10, and 13 d after NaCl treatment to determine the morphology and physiological and biochemical indices of rice roots. The results showed that NaCl stress significantly inhibited rice growth; disrupted the antioxidant system; increased the rates of malondialdehyde, hydrogen peroxide, and superoxide anion production; and affected the content of related hormones. Malondialdehyde content, hydrogen peroxide content, and superoxide anion production rate significantly increased from 12.57% to 21.82%, 18.12% to 63.10%, and 7.17% to 56.20%, respectively, in the S treatment group compared to the CK group. Under salt stress, foliar sprays of both 5-ALA and DTA-6 increased antioxidant enzyme activities and osmoregulatory substance content; expanded non-enzymatic antioxidant AsA and GSH content; reduced reactive oxygen species (ROS) accumulation; lowered malondialdehyde content; increased endogenous hormones GA3, JA, IAA, SA, and ZR content; and lowered ABA content in the rice root system. The MDA, H 2 O 2 , and O 2− contents were reduced from 35.64% to 56.92%, 22.30% to 53.47%, and 7.06% to 20.01%, respectively, in the AS treatment group compared with the S treatment group. In the DS treatment group, the MDA, H 2 O 2 , and O 2− contents were reduced from 24.60% to 51.09%, 12.14% to 59.05%, and 12.70% to 45.20%. In summary, NaCl stress exerted an inhibitory effect on the rice root system, both foliar sprays of 5-ALA and DTA-6 alleviated damage from NaCl stress on the rice root system, and the effect of 5-ALA was better than that of DTA-6.
研究领域:
植物学
·
农学
✓ 已验证
DOI
PubMed
高影响因子
ANNALS OF MICROBIOLOGY
·
2017
·Vol. 68
·期 1
·27-34
·
IF 1.122
Xiao Yaqing,Li Peijun,Xu Mei,Wang Wu,Chen Conggui
The objective of this study was to evaluate the ability of five strains of meat-borne bacteria to decrease N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) and to elucidate the mechanism in Mann-Rogosa-Sharp (MRS) broth. Lactobacillus pentosus R3 was found to be the most effective in decreasing the concentration of the two N-nitrosamines (NAs) in MRS broth, with a rate of 22.05% for NDMA and 23.31% for NDEA. The concentration of the two NAs could not be reduced by either extracellular metabolites or intracellular extracts of Lb. pentosus R3 (P > 0.05), and proteinaceous substances in the cell debris were found to be responsible for the decrease. These were surface-layer proteins (SLPs) located on the cell wall. Therefore, the decrease in NDMA and NDEA by Lb. pentosus R3 is associated with its SLPs. Lb. pentosus R3 may be developed as a starter culture in the production of fermented foods with lower NAs.
研究领域:
食品科学
·
微生物学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子