MICROPOROUS AND MESOPOROUS MATERIALS
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2022
·
IF 5.876
Jinhao Du,Ruting Yuan,Feng Lin,Lijun Liao,Ge Yang,Furong Tao,Yuezhi Cui,Christine E.A. Kirschhock
Azonia-spiro compounds have been reported as organic templates for synthesizing many extra-large pore high silica zeolites , often isomorphically substituted by germanium . However, these templates are usually obtained in the presence of sodium hydroxide, leading to persisting sodium ions in the final products. Sodium cations may compete with azonia-spiro organics as templates during zeolite synthesis. Therefore, effect of any residual sodium cations on the synthesis results needs to be investigated. This work documents the effect of sodium ions on zeolite formation using four structurally similar azonia-spiro compounds as templates. Different silicogermanate zeolites (UTL, an unknown zeolitic phase, etc.) were formed in the absence of sodium cations. Notably, the syntheses of silicogermanate UTL and siliceous MTW zeolites using azonia-spiro[4,6] and [6,6] are reported for the first time. Controlled amounts of sodium chloride were added to zeolite crystallization mixtures without residual sodium hydroxide. In the presence of 0.005–0.1 mol/L Na + , silicogermanate zeolites were the dominant phases. Further increasing the Na + concentration to 0.152 and 0.317 mol/L, formation of UTL and an unknown silicogermanate phase were inhibited in favor of a dense sodiumgermanate (Na 4 Ge 9 O 20 ). Moreover, sodium ions next to azonia-spiro organic templates also influence the morphologies of the MTW zeolites. The observed high sensitivity of zeolite formation in the presence of even traces of sodium therefore has impact on synthesis protocols of large pore silicogermanate zeolites. This work highlights how small, often overlooked, factors in inorganic material synthesis can drastically change the outcome.
研究领域:
材料科学
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化学
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
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2013
·
IF 4.387
Shanshan Zeng,Lu Wang,Teng Chen,Haibin Qu
A surface flowing mode sample holder was designed as an alternative sampling strategy for direct analysis in real time mass spectrometry (DART-MS). With the sample holder, the on-line coupling of macroporous resin column chromatography with DART-MS was explored and the new system was employed to monitor the column chromatography elution process of Panax notoginseng . The effluent from macroporous resin column was first diluted and mixed with a derivatization reagent on-line, and the mixture was then directly transferred into the ionization region of DART-MS by the sample holder. Notoginsenosides were methylated and ionized in a metastable helium gas stream , and was introduced into MS for detection. The on-line system showed reasonable repeatability with a relative standard deviation of 12.3% for the peak area. Three notoginsenosides, i.e. notoginsenoside R 1 , ginsenoside Rb 1 and ginsenoside Rg 1 , were simultaneously determined during the eluting process. The alteration of the chemical composition in the effluent was accurately identified in 9 min, agreeing well with the off-line analysis. The presented technique is more convenient compared to the traditional UPLC method. These results suggest that the surface flowing mode DART-MS has a good potential for the on-line process monitoring in the pharmaceutical industry .
研究领域:
分析化学
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中药学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2014
·
IF 3.259
Peng-Cheng Sun,Ying Liu,Yue-Tao Yi,Hong-Juan Li,Ping Fan,Chuan-Hai Xia
In the present study, a simple and efficient method for the preparative separation of 3-CQA from the extract of Helianthus tuberosus leaves with macroporous resins was studied. ADS-21 showed much higher adsorption capacity and better adsorption/desorption properties for 3-CQA among the tested resins. The adsorption of 3-CQA on ADS-21 resin at 25 °C was fitted best to the Langmuir isotherm model and pseudo-second-order kinetic model. Dynamic adsorption/desorption experiments were carried out in a glass column packed with ADS-21 to optimise the separation process of 3-CQA from H. tuberosus leaves extract. After one treatment with ADS-21, the content of 3-CQA in the product was increased 5.42-fold, from 12.0% to 65.2%, with a recovery yield of 89.4%. The results demonstrated that the method was suitable for large-scale separation and manufacture of 3-CQA from H. tuberosus leaves.
研究领域:
植物化学
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天然产物开发
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2020
·
IF 2.627
Ling Meng,Xia Gui,Zhi Yun
Oridonin, one of the active ingredients in Rabdosia rubescens ( R. rubescens ), has been reported to induce cell apoptosis and cell cycle arrest in many cancers. Conventional extraction methods tend to result in unsatisfied enrichment and poor quality of oridonin present in a given biomass. This paper aims to evaluate the performance and separation characteristics of four different macroporous resins to arrive at the most suitable methodology for the isolation and purification of high-quality oridonin. Static absorption kinetics, thermodynamic and dynamic adsorption were evaluated. HP-20 was selected for further study due to its high adsorption capacity of 32 mg·g −1 and desorption ratio with 98.5%. The pseudo-second-order model was considered to be the most suitable for kinetic results, and Langmuir model was chosen to better describe the absorption thermodynamics. Under optimum conditions (flow rate of 4 ml·min −1 , bed depth with 6 cm and initial concentration of 2.15 mg·ml −1 ), the effective content of oridonin increased from 33.9% to 79.1% in the dry extract with a recovery of 81% and the purity of oridonin improved from 76% to 93%. The results confirm that HP-20 provides an efficient method to purify most oridonin from R. rubescens .
研究领域:
药用植物学
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药物化学
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生物工程
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
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2012
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IF 2.947
Hui-xue Ren,Han-jie Ying,Ping-kai Ouyang,Ping Xu,Jing Liu
Efficient and pollution-free catalysts play an essential role in the ultimate biodegradation of products in the synthesis of biodegradable and recyclable poly( l -lactic acid) (PLLA). Therefore, macroporous resin was utilized as the solid acid for the first time, on which lactate that could be absorbed in vivo was composited to catalyze the synthesis of PLLA. It was discovered that macroporous resin Amberlyst-15 showed good catalytic activity in oligomerization and polymerization, and lactate showed different catalytic efficiencies due to the differences in ionic radius and ionic charge. Compared to the traditional catalysts of SnCl 2 ·2H 2 O/TSA, the composite catalyst can improve the quality, yield and optical purity of its product, which can also be recycled without any residual in products. PLLA with molar mass of about 110,000 g mol −1 was synthesized at the yield of 93%. The product exhibits pure color (white), and its optical purity and crystallinity are 98% and 55%, respectively. A possible catalytic mechanism was proposed. The resulting PLLA products were characterized by GPC, 1 H NMR, DSC, and polarimeter.
研究领域:
材料科学
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生物工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 66
·53441-53447
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IF 3.84
Jia Ma,Yunlong Ning,Cairong Gong,Gang Xue,Guoliang Fan
Three-dimensionally ordered macroporous (3DOM) SiOC was successfully fabricated on a cordierite monolith inner wall of a polystyrene (PS) sphere template through a colloidal crystal templating (CCT) method (named as 3DOM SiOC/cordierite). And perovskite-type LaCoO3 (LCO) mixed metal oxides, prepared by a facile sol–gel process, were coated onto the wall of the 3DOM SiOC/cordierite by a simple impregnation-sintering approach (named as LCO/3DOM SiOC/cordierite). The morphological and physicochemical properties studies indicate that the 3DOM structure has excellent connectivity, a large specific surface area, and applicable pore size. And the 3DOM structure plays an important role in preventing aggregation of the targeted catalyst particles, improving the contact condition between catalysts and soot as well as enhancing the reducibility of the LCO. The subsequent investigation on the catalytic performance of the 3DOM samples for diesel soot combustion shows that the 3DOM texture offers the catalyst a lower soot combustion temperature than a conventional catalyst, and the LCO/3DOM SiOC/cordierite reduces the combustion temperature even further while avoiding the rise of back-pressure effectively as well.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Xiaoyun Liu,Su Yan,Hua Zhou,Hao Wu,Shuya Wang,Xiaoyu Yong,Jun Zhou
Glabridin has beneficial antioxidant, anti-inflammatory, and tyrosinase inhibitory activities, with many applications in the pharmaceutical and cosmetics industries. After industrial extraction of glycyrrhizic acid, Glycyrrhiza glabra residue contains abundant glabridin. Glabridin was extracted from Glycyrrhiza glabra residue with a deep eutectic solvent (DES), followed by the recovery of the glabridin by organic solvent extraction, and then partial purification with hydrophobic macroporous resin. Ethyl acetate was the best extraction solvent, with an extraction yield of 91.63 %. Twelve macroporous resins were evaluated and LSA-21 yielded the best recovery of glabridin. Adsorption of glabridin by LSA-21 resin conformed to pseudo-second-order kinetic and Langmuir models. The thermodynamic parameters ΔH (enthalpy change) and ΔG (Gibbs free energy) were both negative, ΔS (entropy change) was positive. These results indicated that LSA-21 resin spontaneously and exothermically adsorbs glabridin to form a monolayer. The optimum conditions for separating and purifying glabridin by LSA-21 resin were 50 % ethanol aqueous solution(v/v) with a concentration of 56.90 µg/mL glabridin at a flow rate of 2 bed-volumes (BV)/h, and elution with 4 BV of ethanol at 2 BV/h, producing a glabridin yield of 97.80 %. The resin could be reused four times and the glabridin yield slightly decreased to 94 %. The overall recovery of glabridin from the DES Glycyrrhiza glabra extract solution after the ethyl acetate and LSA-21 steps was 89.61 %, with a purity of 17.38 %. This approach is an effective method for the recovery and purification of glabridin from a DES extract of Glycyrrhiza glabra residue, which has potential industrial application for producing glabridin and other natural plant products.
研究领域:
植物化学
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药学
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生物工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 23
·13583-13590
·
IF 3.119
Ju Huang,Yaqi Fan,Guanqun Zhang,Yanhang Ma
Introduction of meso-/macropores into the intrinsic microporous framework of zeolites has raised substantial interest in catalytic reactions with bulky reactants. Herein, we report the formation of secondary meso-/macropores in Silicalite-1 zeolite by a solvent-free mechanochemical grinding process. The strategy allows the preservation of high crystallinity and microporosity of the pristine zeolite, and the generation of mesopores at room temperature and marcopores at higher temperatures. The roles of the tetrapropylammonium bromide (TPABr) and ammonium fluoride (NH4F) have been proposed and demonstrated. A protective layer is formed by TPA+ ions bonded with the surficial defects to shield the outer surface from the direct attack by F−. Instead, F− diffuses into the micropore system in a local aqueous environment within zeolite formed by the mechanochemical reaction. As a result, freely diffused F− selectively dissolves zones with structural defects to form secondary pores inside the zeolite. Moreover, this strategy proves highly effective in encapsulation of nanoparticles (Pt, Co) in the meso-/macropores of Silicalite-1 zeolite, forming a yolk–shell composite catalyst for potential applications.
研究领域:
催化科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Crystals
·
2022
·Vol. 12
·期 6
·778
·
IF 2.67
Shunhong Dong,Juan Wu,Lanlan Huang,Hong-En Wang
Narrowing the band gap and increasing the photodegradation efficiency of TiO2-based photocatalysts are very important for their wide application in environment-related fields such as photocatalytic degradation of toxic pollutants in wastewater. Herein, a three-dimensionally ordered macroporous Pt-loaded TiO2photocatalyst (3DOM Pt/TiO2) has been successfully synthesized using a facile colloidal crystal-template method. The resultant composite combines several morphological/structural advantages, including uniform 3D ordered macroporous skeletons, high crystallinity, large porosity and an internal electric field formed at Pt/TiO2interfaces. These unique features enable the 3DOM Pt/TiO2to possess a large surface for photocatalytic reactions and fast diffusion for mass transfer of reactants as well as efficient suppression of recombination for photogenerated electron-hole pairs in TiO2. Thus, the 3DOM Pt/TiO2exhibits significantly enhanced photocatalytic activity. Typically, 88% of RhB can be degraded over the 3DOM Pt/TiO2photocatalyst under visible light irradiation (λ ≥ 420 nm) within 100 min, much higher than that of the commercial TiO2nanoparticles (only 37%). The underlying mechanism for the enhanced photocatalytic activity of 3DOM Pt/TiO2has been further analyzed based on energy band theory and ascribed to the formation of Schottky-type Pt/TiO2junctions. The proposed method herein can provide new references for further improving the photocatalytic efficiency of other photocatalysts via rational structural/morphological engineering.Keywords:3D ordered macropores;TiO2;Pt loading;photocatalysis;Schottky junction
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2022
·Vol. 14
·期 38
·3727-3738
·
IF 3.532
Chao Huang,Hongwei Wang,Yunjia Xu,Shujuan Ma,Bolin Gong,Junjie Ou
Heavy metal pollution has spread around the world with the development of industry, posing a major threat to human health. It is urgent to design and fabricate bifunctional materials for detection and adsorption of heavy metal ions. Herein, poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) microspheres, a kind of common macroporous adsorption resin (MAR), were employed as the matrix, and carbon dots (CDs) with excellent optical properties were grafted onto the surface of MAR by surface-initiated atom transfer radical polymerization (SI-ATRP) and photo-initiated “thiol-yne” click chemistry. The synthesized MAR@poly(PA)@CD could produce fluorescence quenching with Fe3+. A simple fluorescence spectrometric method for detection of Fe3+ was established. The fluorescence intensity of MAR@poly(PA)@CD decreased linearly with the concentration of Fe3+ in the range of 0–70 nmol L−1, with a limit of detection (LOD) of 6.6 nmol L−1, which had the potential for trace detection. In addition, after SI-ATRP modification, many adsorption sites were generated on the surface of MAR, and the adsorption capacity for Fe3+ was 23.8 mg g−1. Isothermal and kinetic adsorption experiments were more consistent with the Langmuir model (r = 0.9992) and pseudo-second-order model (r = 0.9902), indicating that the adsorption was monolayer adsorption and chemical adsorption, respectively. MAR@poly(PA)@CD with dual functions of detecting and adsorbing Fe3+ was successfully prepared, showing great application prospects in the environmental field.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Jiali Wen,Chuanqi Zhang,Yang Zhang,Zhifeng Zeng,Fei Ma,Jiuxing Jiang
The 24-membered ring - SYT type extra-large pore zeolite , denoted as DESO-SYSU-3, has been synthesized by employing N,N′-diethylsophoridine and trimethylsulfanium in a mixed-template system, where the N,N′-diethylsophoridine and trimethylsulfanium played different roles in the crystallization process . A single usage of N,N′-diethylsophoridine led to the formation of an unknown phase (donated as SYSU-5). These results reveal that the utilization of alkaloid-derived organic structure-directing agents (OSDAs) is an efficient synthetic strategy to produce specific extra-large pore zeolites and related structures. Compared to the prototype SYSU-3, the addition of TMSF into the system not only improved the silicon content in the framework of DESO-SYSU-3 but also facilitated the generation of carbon dots (CDs) confined in extra-large pore structure . The structure and the proposed formation mechanism of CDs were investigated based on HRTEM, XPS, FI-IR, UV–Vis, Raman and photoluminescence spectrum. The CDs@zeolite composite exhibited intriguing optical properties of both fluorescence and room temperature phosphorescence, respectively. This work extends extra-large pore zeolite as the matrix for the development of CDs@zeolite composites with tunable optical properties .
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
BIOTECHNOLOGY LETTERS
·
2019
·Vol. 42
·期 2
·269-276
·
IF 2.154
Cai Xinyong,Zhang Mengjie,Wei Wei,Zhang Yinjun,Wang Zhao,Zheng Jianyong
A novel enzyme immobilization method employing metal–organic framework (MOF) encapsulation and macroporous resin adsorption was developed in this study. Candida antarctica lipase B (CALB) was firstly encapsulated onto metal–organic frame structures (Zeolitic imidazole framework-8, ZIF-8) and further bonded to macroporous resin by physical adsorption. Under optimized immobilization conditions, the activity of the prepared immobilized lipase (CALB-ZIF-8@D101) determined via the methyl esterification of oleic acid was 38.4 U/mg. Compared with free lipase, the immobilized lipase exhibited improved thermal and operational stability and organic solvent tolerance. These results demonstrate that the immobilization method of ZIF-8 encapsulation and macroporous resin adsorption enhanced enzyme properties at a superior level.
研究领域:
生物化学
·
酶工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）