SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2024
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IF 4.3
Yi Gu,Yang Jiao,Ya Ruan,Jing Yang,Yaling Yang
Herein, a nanocomposite of Cu,Ce-containing phosphotungstates (Cu,Ce-PTs) with outstanding laccase-like activity was fabricated via a one-pot microwave-assisted hydrothermal method. Notably, it was discovered that both Fe 3+ and Cr 6+ could significantly enhance the electron transfer rates of Ce 3+ and Ce 4+ , along with generous Cu 2+ with high catalytic activity, thereby promoting the laccase-like activity of Cu,Ce-PTs. The proposed system can be used for the detection of Fe 3+ and Cr 6+ in a range of 0.667–333.33 μg/mL and 0.033–33.33 μg/mL with a low detection limit of 0.135 μg/mL and 0.0288 μg/mL, respectively. The proposed assay exhibits excellent reusability and selectivity and can be used in traditional Chinese medicine samples analysis.
研究领域:
生物化学
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环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
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2020
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IF 5.006
Phyu Thin Wai,Pingping Jiang,Yirui Shen,Pingbo Zhang,Qian Gu
The efficient catalysts were designed to allow the entry and release of reactants and products into the mesoporous SBA-15 in which the active sites, peroxophosphotungstate, were entrapped by silylation with three different silylating agents (C 3 , C 5 , and C 8 arm). The as-prepared catalysts were characterized by elemental analysis, ICP analysis, TGA, XRD, N 2 adsorption/desorption, SEM, TEM, and FT-IR spectra. Their catalytic performances were tested for the epoxidation of soybean oil using different parameters such as temperature, H 2 O 2 to unsaturation molar ratio, catalyst loading and stirring speed. The resulting epoxidized soybean oil was analyzed qualitatively and quantitatively by FT-IR and 1 HNMR. The results confirmed that the catalyst silylated with C 8 arm is promising for the synthesis of epoxides of long-chain carbon and reusable at least three times without obvious decrease in activity. Moreover, use of H 2 O 2 oxidant and free of solvent in the epoxidation reaction are the main advantages of these catalysts.
研究领域:
催化化学
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材料科学
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绿色化学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 9
·1554
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IF 5.3
Min Zheng,Xiangzhou Li,Youyi Xun,Jianhua Wang,Dulin Yin
It is presented that the activated carbon was carboxylated with hydrogen peroxide and then acylated with 2-methylimidazole to prepare the porous carbon support with a surface imidazolated modification. Through the adsorption of phosphotungstic acid on the fundamental site of an imidazolyl group and then adjusting the acid strength with the ammonia molecule, a catalytic carbon material immobilized with ammonium phosphotungstate (AC-COIMO-NH4PW) was obtained, which was used to catalyze a one-pot reaction of convenient α-pinene and hydrogen peroxide to sobrerol. The bifunctional active site originated from the dual property of ammonium phosphotungstate, as the oxidant and acid presenting a cooperatively catalytic performance, which effectively catalyzes the tandem epoxidation–isomerization–hydration of α-pinene to sobrerol, in which the solvent effect of catalysis simultaneously exists. The sobrerol selectivity was significantly improved after the acid strength weakening by ammonia. Monomolecular chemical bonding and anchoring of ammonium phosphotungstate at the basic site prevented the loss of the active catalytic species, and the recovered catalyst showed excellent catalytic stability in reuse. Using acetonitrile as the solvent at 40 °C for 4 h, the conversion of α-pinene could reach 90.6%, and the selectivity of sobrerol was 40.5%. The results of five cycles show that the catalyst presents excellent stability due to the tight immobilization of ammonium phosphotungstate bonding on the imidazolized activated carbon, based on which a catalytic-cycle mechanism is proposed for the tandem reaction.Keywords:sobrerol;α-pinene;catalytic synthesis;ammonium phosphotungstate;activated carbon
研究领域:
化学工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
SOLID STATE SCIENCES
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2023
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IF 3.5
Yijun Yin,Xiaoyi Huang,Wang Wang,Xia Liu
Carbon and oxygen co-doped phosphotungstate were successfully prepared by one-pot thermal treatment with phosphotungstic acid (HPW) and melamine-cyanuric acid supramolecule (MCA) as precursors. Based on the results of X-ray photoelectron spectra (XPS), UV–visible diffuse reflectance spectroscopy (UV–vis DRS), and Photoluminescence (PL) measurements, the existence of C O in CNPW-8-420 has been confirmed. Carbon and oxygen which are co-doped as C O in the Keggin structure of phosphotungstate are contributed to the separation of charge carriers and can increase the amount of the photocatalysis active sites. With the amount of HPW increasing, MCA decomposed in CNPW-8-420 and CNPW-20-420 without synthesizing g-C 3 N 4 , leading to in-situ doped of C O. Furthermore, the increase of treatment temperature can cause the supramolecular structure of MCA to overbreak, leading to carbon and nitrogen elements doped in CNPW-8-500. The photocatalytic degradation efficiency rate constant of CNPW-8-420 is 0.40 h −1 and it can be reused 3 times with no obvious change. LC−MS/MS revealed the most likely photocatalytic degradation pathway and intermediates of imidacloprid including imidacloprid olefin, guanidine-type imidacloprid, imidacloprid urea, 6-chloronicotinic acid, 5-hydroxy-imidacloprid, and 4,5-dihydroxy-imidacloprid. This study provides a promising strategy for the construction of co-doped POMs photocatalysts using different supramolecule precursors.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2024
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IF 7.2
Yan Gao,Shuhong Jia,Hongyan Zhou,Ziyun Chen,Miao Yan,Jianshe Zhao
s An efficient and sustainable catalyst is urgently needed for the actual oil refining process. Different amounts of peroxophosphotungstate (PW 4 ) were successfully encapsulated into the pore of ZIF-8 framework material to obtain composites (x%-PW 4 @ZIF-8, x = 10.7, 14.6, 27.5 and 34.8) through a stirring process at room temperature for desulfurization of model diesel. The successful encapsulation of the active component PW 4 in the pore was verified by a variety of characterization methods, and there is weak force between the PW 4 and the ZIF-8. The composite 27.5%-PW 4 @ZIF-8 showed good catalytic activity for various sulfides under moderate conditions. In addition, DBT removal rate catalyzed by 27.5%-PW 4 @ZIF-8 could still reach levels of 95.1% after 10 cycles. The high efficiency of activity and excellent reusability are attributed to the high matching of host and guest sizes. This work provides new inspiration for designing and preparing catalysts with high activity and excellent reusability by a simple and environmentally friendly method.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2017
·Vol. 9
·期 21
·4139-4147
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IF 4.803
Yuexiao Song,Feng Xin,Lexiang Zhang,Yong Wang
Graphical That′s radical ! In the homogeneous catalytic oxidation of cyclohexene by transition-metal-substituted phosphotungstates with hydrogen peroxide, allylic oxidation and epoxidation proceed through radical pathways based on transition metals and nonradical pathways based on PW 4 , respectively. Homogeneous catalytic oxidations of cyclohexene by transition-metal-substituted phosphotungstates [PW 11 M(L)O 39 ] m− (PW 11 M, M=Co II , Cu II , Fe III , Ni II , Mn II , L=H 2 O or absence) with hydrogen peroxide in acetonitrile were experimentally studied. The catalytic activities of allylic oxidation were found to strongly depend on the transition metals, and PW 11 Co showed the highest activity. The product distribution and the catalyst stability were dominated by mole ratio of hydrogen peroxide to PW 11 M, whereby low or high mole ratios led to stable structure of PW 11 M and predominant formation of allylic oxidation products or decomposition of PW 11 M, respectively. Different from the activation of the allylic C−H bond by radicals, the oxidation of C=C double bond was based on tungsten-peroxo species. A reaction mechanism composed of radical and nonradical processes was proposed from NMR, EPR, and kinetic data, to describe the reaction pathways of cyclohexene oxidation.
研究领域:
化学
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 153
·期 10
·3092-3102
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IF 2.936
Li Yongwei,Pan Shiguang,Han Ronghuan,Gao Jian,Liu Dan,Gui Jianzhou
Phosphotungstate organic–inorganic hybrid materials [CH 2 COOHmim]H 2 PW 12 O 40 , [(CH 2 ) 3 COOHmim]H 2 PW 12 O 40 and [Bmim]H 2 PW 12 O 40 with dual catalytic oxidation active centers, including carboxylic acid group and phosphotungstate anion, were synthesized from bisulfate acidic ionic liquid in a one-step method, and well characterized by XRD, 1 H NMR, 13 C NMR, 31 P NMR, FT-IR, and UV–vis. Then, these obtained hybrids were employed as catalysts for the selective oxidation of N-methylmorpholine (NMM) into N-methylmorpholine-N-oxide (NMMO) using H 2 O 2 as an oxidant. As expected, the –COOH functionalized hybrids showed much better activity than the conventional hybrid [Bmim]H 2 PW 12 O 40 , and even much better than the mixture of corresponding ionic liquid and H 3 PW 12 O 40 , suggesting the existence of dual active species and synergistic effect between the cation and phosphotungstate in hybrids. The best catalyst [(CH 2 ) 3 COOHmim]H 2 PW 12 O 40 gave an NMM conversion of 98.7% and selectivity to NMMO of 98.8%. The structural characterization by 31 P NMR, UV–vis, Raman and 13 C NMR analysis of the catalyst before and after oxidation demonstrated the existence of the catalytic active species PW 12 O 40 3− and peroxy carboxylic acid. Finally, a possible catalytic mechanism has been proposed. Graphical Abstract
研究领域:
材料化学
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催化化学
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产品关联
DOI
高影响因子
DESALINATION
·
2025
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IF 9.8
Hui Yang,Baozhong Ma,Shuyang Shi,Jiancheng Yu,Yubo Liu,Zhihe Cao,Chengyan Wang,Yongqiang Chen
Extracting rubidium from brine is critical for addressing the rubidium supply challenge. Ion exchange is an effective method for rubidium recovery, but practically, it faces the challenge that the adsorbent powder is too fine for column operation. Herein, hydrogel beads (AWP@AlG&PVA) were innovatively synthesized through dual crosslinking between sodium alginate and CaCl₂, as well as polyvinyl alcohol and boric acid, incorporating ammonium phosphotungstate (AWP) as the active component, and were employed as adsorbents for rubidium extraction from high-salinity brine. The mercury intrusion pore measurement confirmed that the prepared AWP@AlG&PVA is a porous material, with the majority of pores being large pores. Through systematic adsorption experiments, over 90 % of rubidium was adsorbed from the simulated solution under optimal conditions. The coexisting K + interfered with rubidium adsorption, while Na + , Ca 2+ , and Mg 2+ had no apparent influence. Adsorption kinetic study revealed that Rb adsorption adhered to the pseudo-first-order kinetic model. The adsorption isotherms of AWP@AlG&PVA on Rb + accord with the Freundlich model. XPS and SEM-EDS analyses indicated that the adsorption mechanism was ascribe to ion exchange between NH 4 + and Rb + . Remarkably, the adsorbent exhibited excellent regeneration performance, retaining over 71.3 % of its adsorption ability after undergoing six sequential adsorption-desorption cycles in actual brine. This research suggested that the AWP@AlG&PVA beads address the challenges posed by fine powder and high solubility and are a feasible material for Rb adsorption from high-salinity brine.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
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2018
·Vol. 8
·期 57
·32423-32433
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IF 2.936
Guo Qiu,Xincheng Wang,Chongpin Huang,Yingxia Li,Biaohua Chen
The efficient conversion of carbohydrates to 5-hydroxymethylfurfural (5-HMF) under mild conditions represents a very attractive and promising method of producing important building blocks. In this work, niobium phosphotungstates, with Nb/P molar ratios of 0.6, 1.0, 2.0 and 4.0 (NbPW-06, NbPW-1, NbPW-2, and NbPW-4, respectively) have been prepared by a facile, one-pot, alcohol-mediated thermal process and used for the direct conversion of fructose to 5-HMF. By adding a certain amount of Nb, the surface of the catalyst became enriched in P, and this enrichment was associated with the presence of surface P–OH groups that offered Brønsted acid sites that can activate superficial hydrogen species to facilitate 5-HMF generation. Pyridine-FTIR confirmed the presence of Brønsted and Lewis acid sites, which might play important roles in the dehydration of fructose to 5-HMF. Furthermore, polar aprotic solvents were well-suited for the conversion, and higher yields of 5-HMF were obtained in polar aprotic solvents than in nonpolar solvents. A 5-HMF yield of 96.7% with complete fructose consumption was obtained over NbPW-06 in DMSO at 80 °C after 90 min. In addition, NbPW-06 could be recycled several times without a significant decrease in the catalytic activity. A catalytic mechanism for this reaction was proposed. Moreover, this catalytic system can also be utilized for the dehydration of sucrose and inulin to 5-HMF in satisfactory yields. This study establishes an important platform for the further design of Nb-containing catalysts for the production of 5-HMF from carbohydrates under mild conditions.
研究领域:
化学工程
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催化材料科学
✓ 已验证
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2022
·
IF 5.876
Yan Gao,Miao Yan,Jianshe Zhao
A composite PW 4 @UIO-66-NH 2 /GO was designed and prepared via facile in-situ synthesis method for catalytic oxidation desulfurization of fuel. The proper sizes (window size and pore size) of UIO-66-NH 2 can effective sealing PW 4 as monomolecular active component and prevent PW 4 leaching during the reaction process. At the same time, the introduction of GO can improve the electron transfer of the catalyst. Characterization tests showed that the active component PW 4 was successfully encapsulated with a loading amount of 0.19 mmol/g. The desulfurization results indicated that the PW 4 @UIO-66-NH 2 /GO has excellent catalytic activity, which can remove 99.9% sulfides in model fuel, and the activity did not decrease obviously after repeated use for ten times. The good activity and reusability of PW 4 @UIO-66-NH 2 /GO attributes to the introduction of GO and UIO-66-NH 2 . In addition, based on GC-MS and EPR results, a possible mechanism of desulfurization reaction was proposed.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
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IF 4.326
Yuxin Wu,Zhuo Chen,Yundong Wang,Jianhong Xu
The olefin epoxidation reaction is of great interest in recent years since epoxide is considered an important intermediate for a wide application range. H2O2-based catalytic epoxidation possesses the advantages of being cheap, green, and safe, which are quite advantageous in chemical technology. A phase-transfer catalyst, especially the phosphotungstate catalyst, has been applied in the epoxidation reaction with a high reaction rate and moderate reaction conditions. In this work, a phase-transfer catalyst, [(C18H37)2(CH3)2N]7[PW11O39], has been synthesized, and it showed high catalytic efficiency in styrene epoxidation. The influence of reaction time, temperature, oxidant concentration and amount, catalyst amount, and substrate concentration on the reaction performance was studied. A styrene conversion of 90.1% and selectivity of 90.6% could be achieved at 85 °C for 1 h with 3 equiv of H2O2 and 1.5 mol % catalyst. More importantly, kinetic models for the reaction network have been studied to optimize the reaction conditions and limit the side reactions.
研究领域:
化学工程
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
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2021
·Vol. 31
·期 11
·4195-4208
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IF 3.543
Wang Lulu,Zeng Xiangrui,Wang Haiyan,Wang Yujia
Abstract A series of porous confined ionic liquid phosphotungstate were synthesized by encapsulated of N-(3-sulfopropyl)morpholinium phosphotungstate ([C 3 SO 3 Hnhm] 3 -PW 12 O 40 ) into MIL-101. Then the aforementioned porous confined ionic liquid phosphotungstate as heterogeneous catalyst will be used together with H 2 O 2 for the catalytic synthesis of adipic acid from cyclohexene. During the experiment, the effect of weight content of [C 3 SO 3 Hnhm] 3 PW 12 O 40 on the catalytic performance was investigated in detail. And the chemical structure of the catalyst was also characterized by XRD, FT-IR, 1 H-NMR, SEM–EDX and N 2 adsorption–desorption isotherms. Experimental results revealed that the desired products has been successfully prepared, and the best catalytic performance (81.2% yield of the adipic acid) was obtained under the dose of [C 3 SO 3 Hnhm] 3 PW 12 O 40 was 31wt%, which was almost close to the catalytic activity of original [C 3 SO 3 Hnhm] 3 PW 12 O 40 (85.3% yield of the adipic acid), which was also proved the strategy of packaging ionic liquid phosphotungstate with MIL-101 in this research is feasible. Furthermore, recycled catalytic performance of the catalyst under repeat 6 times was evaluated and the result revealed that the yield in adipic acid was still higher than 80.0%, which also proved that the catalytic active component was stable in the catalyst. Graphic Abstract
研究领域:
化学工程
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催化化学
✓ 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）