Biotechnology for Biofuels and Bioproducts
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2022
·Vol. 15
·期 1
·1-10
·
IF 0
Hua Xia,Zhang ChenHui,Han Jian,Xu Yong
Background Hydroxyl acid is an important platform chemical that covers many industrial applications due to its dual functional modules. At present, the traditional technology for hydroxyl acid production mainly adopts the petroleum route with benzene, cyclohexane, butadiene and other non-renewable resources as raw materials which violates the development law of green chemistry. Conversely, it is well-known that biotechnology and bioengineering techniques possess several advantages over chemical methods, such as moderate reaction conditions, high chemical selectivity, and environmental-friendly. However, compared with chemical engineering, there are still some major obstacles in the industrial application of biotechnology. The critical issue of the competitiveness between bioengineering and chemical engineering is products titer and volume productivity. Therefore, based on the importance of hydroxyl acids in many fields, exploring a clean, practical and environmental-friendly preparation process of the hydroxyl acids is the core purpose of this study. Results To obtain high-purity hydroxyl acid, a microbiological regulation for its bioproduction by Gluconobacter oxydans was constructed. In the study, we found a critical point of chain length determine the end-products. Gluconobacter oxydans catalyzed diols with chain length ≤ 4, forming hydroxyl acids, and converting 1,5-pentylene glycol and 1,6-hexylene glycol to diacids. Based on this principle, we successfully synthesized 75.3 g/L glycolic acid, 83.2 g/L 3-hydroxypropionic acid, and 94.3 g/L 4-hydroxybutyric acid within 48 h. Furthermore, we directionally controlled the products of C5/C6 diols by adjusting pH, resulting in 102.3 g/L 5‑hydroxyvaleric acid and 48.8 g/L 6-hydroxycaproic acid instead of diacids. Combining pH regulation and cell-recycling technology in sealed-oxygen supply bioreactor, we prepared 271.4 g 5‑hydroxyvaleric acid and 129.4 g 6-hydroxycaproic acid in 6 rounds. Conclusions In this study, a green scheme of employing G. oxydans as biocatalyst for superior-quality hydroxyl acids (C2–C6) production is raised up. The proposed strategy commendably demonstrated a novel technology with simple pH regulation for high-value production of hydroxyl acids via green bioprocess developments.
研究领域:
生物化学
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绿色化学
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生物工程
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DOI
PubMed
CATALYSIS LETTERS
·
2019
·Vol. 150
·期 2
·322-331
·
IF 2.372
Wang Kaifeng,Liu Ya,Wu Wufeng,Chen Yu,Fang Lina,Li Wanbin,Ji Hongbing
Abstract In this study, Zr-MOF material (UiO-66) was modified with different metal oxides (CeO 2 , Ga 2 O 3 , and CoO) and employed in the conversion of cellulose to levulinic acid (LA) in aqueous medium. The research results showed that the introduction of the metal oxides increased the acid content of the catalysts, especially in medium-strong acid. The selectivity of LA was related to the type of metal oxide and the content of medium-strong acid. Due to the activity of Ga 2 O 3 and more medium-strong acid, the yield of LA reaches a maximum yield of 32.0 mol% at 513 K for 360 min when Ga 2 O 3 -UiO-66 was employed as the catalysts. The combination of metal oxide and UiO-66 enables the reaction to proceed, providing a new direction for the conversion of cellulose to LA in the aqueous phase. Graphic Abstract In this study, Zr-MOFs material (UiO-66) was modified with different metal oxides (CeO 2 , Ga 2 O 3 , and CoO) and employed in the conversion of cellulose to levulinic acid in aqueous medium. The results indicated that the addition of metal oxides changes the acidity of UiO-66, which improves the catalytic activity. The selectivity of LA was related to the type of metal oxide and the content of medium-strong acid.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY
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2017
·
IF 1.208
Yongli Liu,Qingxiang Zhou
In present work, fluorescent carbon dots (CDs) with an average diameter of 2.5 nm were firstly synthesised by a simple, convenient and low-cost hydrothermal method from chocolate. The obtained CDs possessed fine monodispersity and bright blue fluorescence that was strongest at an excitation wavelength of 360 nm and had a comparable quantum yield of 12% (in case of dots prepared in presence of nitric acid). The emission peak depended on the excitation wavelength in the range from 320 to 440 nm. Ionic strength had a weak effect up to 1.0 M and then no significant change was found in the range of 1.0–4.5 M. The fluorescence intensity of CDs displayed good pH adaptability and a linear dependence on the pH change in the range of pH 1.0–3.0 and pH 9.0–12.5, which have promising potentials for pH sensor.
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
NANOTECHNOLOGY
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2022
·Vol. 33
·期 21
·215705
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IF 3.953
Zhen Mao,Hui Li,Na Gan,Zili Suo,Huan Zhang,Qiang Zhao
Fixed carbon source and different dopants are mainly used to study the effect of heteroatoms on the structure and properties of carbon dots (CDs). As reactants, some dopants with conjugated structure and high nitrogen content may have important contributions to the structure and properties of doped CDs in addition to providing heteroatoms. Herein, to study the effect of fixed dopant on the structure and properties of CDs, three different CDs were synthesized using nicotinamide (NAA) and three common α-hydroxy acids (4–5 carbon atoms), and the optimal conditions were determined by orthogonal experimentation. Transmission electron microscopic micrographs showed that the average size of CDs based on nicotinamide are relatively large, up to 19.40 nm. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy demonstrated that these CDs have graphite nitrogen and several functional group structures. Ultraviolet–visible absorption spectra, fluorescence emission spectra, and fluorescence lifetime illustrated that these CDs have similar emission centers (460–470 nm) and fluorescence processes. The influence of carbon source on the surface structure of CDs was determined by systematically analyzing the response of these CDs in different pH ranges. DFT calculations revealed the distribution characteristics of the electrons in the excited state at the HOMO and LUMO energy levels of CDs. All the above characterizations and calculations proved that NAA is a desirable dopant with an important contribution to the structure and properties of CDs.
研究领域:
材料科学
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化学
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DOI
PubMed
高影响因子
FUEL
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2022
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IF 8.035
Lungang Chen,Yong Liu,Xinghua Zhang,Jianguo Liu,Qi Zhang,Longlong Ma
Catalytic conversion of biomass to liquid fuel is one of critical part to ease dependence on fossil fuel. Herein, a route of transformation of biomass-derived furfural and levulinic acid into long-chain hydrocarbon fuels was developed. A C20 oxygenate with 95 % mol yield was firstly synthesized through condensation-polymerization reactions catalyzed by NaOH. Various techniques were employed to verify the chemical structure of the C20 oxygenate. The condensation mixture was then directly subjected to hydrodeoxygenation reaction to prepare long-chain hydrocarbons with a catalytic system of Pd/C and H 3 PO 4 in aqueous phase. A 57.1 % weight yield of liquid fuel was obtained with main products of C12, C14, and C18 hydrocarbons. The mass percent of carbon and hydrogen in fuel was significant improved to 95.91 %, as well as the high heat value was increased to 47.04 MJ/kg.
研究领域:
能源化学
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催化化学
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DOI
高影响因子
International Journal of Environmental Research and Public Health
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2022
·Vol. 19
·期 23
·16298
·
IF 4.614
Fenfen Wang,Dongxue Qu,Shaoshuai Wang,Guojun Liu,Qiang Zhao,Jiaxue Hu,Wendi Dong,Yong Huang,Jinjia Xu,Yuhui Chen
Catalytic conversion of cellulose to liquid fuel and highly valuable platform chemicals remains a critical and challenging process. Here, bismuth-decorated β zeolite catalysts (Bi/β) were exploited for highly efficient hydrolysis and selective oxidation of cellulose to biomass-derived glycolic acid in an O2atmosphere, which exhibited an exceptionally catalytic activity and high selectivity as well as excellent reusability. It was interestingly found that as high as 75.6% yield of glycolic acid over 2.3 wt% Bi/β was achieved from cellulose at 180 °C for 16 h, which was superior to previously reported catalysts. Experimental results combined with characterization revealed that the synergetic effect between oxidation active sites from Bi species and surface acidity on H-β together with appropriate total surface acidity significantly facilitated the chemoselectivity towards the production of glycolic acid in the direct, one-pot conversion of cellulose. This study will shed light on rationally designing Bi-based heterogeneous catalysts for sustainably generating glycolic acid from renewable biomass resources in the future.Keywords:biomass;cellulose;Bi/β;hydrolysis oxidation;glycolic acid
研究领域:
化学工程
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催化科学
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DOI
PubMed
高影响因子
CATALYSIS COMMUNICATIONS
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2017
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IF 3.33
Yanxiu Liu,Hu Li,Jian He,Wenfeng Zhao,Tingting Yang,Song Yang
A series of niobium-containing catalysts were prepared by hydrothermal synthesis method, and characterized by NH 3 -TPD, TEM, XRD, N 2 adsorption-desorption and pyridine-adsorption FT-IR techniques. Fe-NbP (Fe-doped niobium phosphate) with higher total acid density (3.59 mmol/g) and appropriate Brønsted/Lewis acid ratio (1.32) was found to show superior activity in production of levulinic acid (LA) from glucose, and a high LA yield of 64.2% was achieved at 180 °C in 3.0 h. The effect of various reaction parameters such as temperature, time, catalyst dosage, and substrate concentration on LA production has been investigated. The catalyst can be recycled for several times without significant loss of activity.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
iScience
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2023
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IF 5.8
Lingjun Zhu,Hao Xu,Xiaoyan Yin,Shurong Wang
With hydrothermal reaction, lignocellulosic biomass can be efficiently converted into furfural (FF) and levulinic acid (LA), both of which are key platform compounds that can be used for the subsequent preparation of aviation fuels. In order to reduce the acid concentration in traditional hydrolysis and provide a reaction system with good catalytic activity, we propose a biomass conversion route as dilute acid hydrolysis coupled with solid acid catalysis. Firstly, at different temperatures, the hemicellulose and cellulose in corn stover were step-hydrolyzed by sulfuric acid solution with a concentration of 0.9 wt. % to produce xylose and glucose, with conversion reaching 100% and 97.3%, respectively. Subsequently, a new resin-derived carbon-based solid acid catalyst was used to catalyze the aforementioned saccharide solutions to obtain FF with yield of 68.7 mol % and LA of 70.3 mol %, respectively. This work provides a promising approach for the efficient production of bio-aviation fuel precursors.
研究领域:
生物化学
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可再生能源
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DOI
PubMed
高影响因子
LUMINESCENCE
·
2021
·Vol. 36
·期 8
·2022-2027
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IF 2.464
Yang Liu,Jia Jia,Tong Liao,Jin Luo,Xinfeng Zhang
A new method based on the enantioselective recognition of porous organic cages CC3-R was established for the first time. Porous organic cages are widely used for separation, adsorption and host–guest interaction sensing, but are rarely used for fluorescence sensing. Based on the inherent chiral environment of CC3-R and the inherent fluorescence properties of the organic ligands constituting the cage, when different chiral monomers diffuse into the cage, different effects occur to produce changes in fluorescence. We found for the first time that the fluorescence of CC3-R can be enhanced and quenched by tyrosine and mandelic acid, respectively, and that different chiral monomers are enhanced or quenched differently at the same concentration. Unlike the chiral recognition of other composite luminescent materials, the chiral porous organic cage not only utilizes its own host–guest effect for chiral recognition, but also utilizes the organic ligands constituting the cage for luminescence recognition. This work provides an alternative method to accomplish chiral recognition other than chromatography, that is using porous organic cages (POC), but it can show the advantages of simplicity, low cost and high sensitivity. We believe this work could provide valuable thoughts in the exploration of POC in chiral recognition as new FL probes for the future.
研究领域:
化学
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材料科学
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分析化学
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DOI
高影响因子
ChemSusChem
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2020
·Vol. 13
·期 21
·5683-5689
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IF 7.962
Zhenbing Xie,Bingfeng Chen,Fangfang Peng,Mingyang Liu,Huizhen Liu,Guanying Yang,Buxing Han
Graphical A sustainable conversion : Developing highly efficient catalytic systems for amino acid productions from renewable bio-derived chemicals is very attractive for a sustainable future. N-doped carbon nanotube-supported Ru nanoparticles (Ru/N−CNTs) display excellent performance in the amination of bio-derived hydroxy acids into amino acids. The high-performance can be correlated with high dispersion of Ru nanoparticles and electronic effect resulting from the N-dopant. The amino acids have extensive applications, and their productions from biomass-derived feedstocks are very attractive. In this work, the synthesis of amino acids by amination of bio-derived hydroxy acids with ammonia over different metallic nano-catalysts supported on various supports is studied. It is found that Ru nano-catalysts on the nitrogen-doped carbon nanotubes (Ru/N−CNTs) have an outstanding performance for the reaction. Different hydroxy acids can be catalytically converted into the corresponding amino acids with yields up to 70.0 % under mild conditions, which is higher than those reported. The reasons for the high efficiency of the catalyst are investigated, and the reaction pathway is proposed on the basis of control experiments.
研究领域:
生物化学
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催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Surfaces and Interfaces
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2024
·
IF 5.7
Yuqing Xu,Beibei Cui,Xueqin Zhang,Ying Sun,Baoping Lin
The Cu@Ag core-shell particles are the highly anticipated functional materials in electronic applications which are required to be high electrical conductivity, good thermal properties and low cost. However, it remains a challenge to obtain a completely and uniformly coated Ag shell in low silver content. During the coating process, it is essential to regulate the reduction of Ag + on the surface of Cu to ensure uniformly silver shell. We developed a strategy to prepare uniformly coated Cu@Ag particles by employing hydroxy acids as complexing agents with “double-sided adhesive” function. Compared to conventional complexing agents, the employed hydroxy acids can not only coordinate with Ag + but also complex with Cu due to the more carboxyl and hydroxyl groups which act like a “double-sided adhesive”, that can pull Ag + to the surface of Cu, and then accomplish the coating of Ag with replacement and reduction reaction. The impact of different types of hydroxy acids as complexing agents on the coating effect of silver-clad copper powder was investigated when the silver addition was 15 %. Results indicated that the obtained Cu@Ag particles with tannic acid as complexing agent show high coating quality layer with low surface sliver content (11.4 %). Moreover, the obtained Cu@Ag particles exhibit good dispersibility, promising thermal stability and low electrical resistivity (30 μΩ·cm).
研究领域:
材料科学
·
电子应用
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2015
·Vol. 26
·期 5
·449-456
·
IF 1.757
Xiangyu Liu,Jingwen He,Yile Niu,Yefei Li,Ding Hu,Xinnian Xia,Yanbing Lu,Weijian Xu
Photo-responsive block copolymer mPEG-b-poly(Tyr)-g-NB was prepared by introduction of o -nitrobenzyl ester group into the side chain of amphiphilic poly(ethylene glycol)-b-poly( α -hydroxy acids) (mPEG-b-poly(Tyr)) containing pendent alkynyl group via copper-catalyzed azide-alkyne cycloaddition reaction. The amphiphilic mPEG-b-poly(Tyr) was synthesized via the ring-opening polymerization of O -carboxyanhydrides, with monomethoxy poly(ethylene glycol) (mPEG) as macroinitiator. The molecular structure, self-assembly, and photo-controlled release of the obtained mPEG-b-poly(Tyr)-g-NB were thoroughly investigated. mPEG-b-poly(Tyr)-g-NB could self-assemble into spherical micelles in water and showed disassembly under UV light irradiation, which was demonstrated by means of UV-vis spectroscopy, scan electron microscopes, and dynamic light scattering measurement. Fluorescence emission measurements demonstrated that Nile red, encapsulated by micelles, can be released upon UV irradiation. This study provides a convenient way to construct smart poly( α -hydroxy acids)-based nanocarriers for controlled release of hydrophobic drugs. Copyright © 2015 John Wiley & Sons, Ltd.
研究领域:
材料科学
·
药物递送
·
高分子化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）