Biotechnology for Biofuels and Bioproducts
·
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
RUSSIAN JOURNAL OF APPLIED CHEMISTRY
·
2023
·Vol. 95
·期 10
·1618-1626
·
IF 0.9
Ren Qinghui,Qian Linfeng,Yao Yanhui,Wen Yazhou,Shi Xiaohua
Abstract Cyanuric acid is an organic intermediate widely used in organic synthesis, and the traditional production method of cyanuric acid is the pyrolysis urea method. Due to the shortcomings of uneven mass transfer, many by-products and poor environmental friendliness, the production of cyanuric acid is extremely limited. In this paper, an effective method has been developed to synthesize cyanuric acid with high yield in a short period of time through the addition-elimination reaction of dihydric alcohol and urea under alkaline conditions. The reaction time, molar ratio of reactants, reaction temperature and other influencing factors were studied. Under optimized conditions, the yield of cyanuric acid is over 90%. And further the proposed reaction mechanism is verified. The synthetic method provided in this article has the advantages of easy availability of raw materials and reusability, simple operation and short reaction time, which makes the method novel and environmentally friendly.
研究领域:
有机化学
·
环境科学
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产品关联
DOI
高影响因子
POLYMER TESTING
·
2019
·
IF 2.943
Haifei Zhang,Fengfan Zhu,Qinghe Fu,Xiaoxiang Zhang,Xinbao Zhu
Expoxy acylated ricinoleic acid binary alcohol ether ester (EARABAEE) is a kind of novel bio-based environmental-friendly plasticizer . EARABAE was synthesized from ricinoleic acid and binary alcohol ether and it's chemical structure was characterized by FT-IR, 1 H NMR, ESI-TOF-MS. EARABAEE was mixed with the poly(vinyl chloride) (PVC) and mechanical property was investigated. The static mechanical property tests indicated that the PVC film plasticized by epoxy benzoylated ricinoleic acid ethylene glycol butyl ether ester (2c) has better tensile strength and the film plasticized by epoxy acetylated ricinoleic acid propylene glycol methyl ether ester (3d) has higher elongation at break. The dynamic mechanical property was evaluated by balanceable torque and mixing process energy, Haake rheometer tests showed that the 3d-plasticized PVC film has bigger balanceable torque and mixing process energy. In addition, the proportion of 3d and DOTP markedly affected the dynamic mechanical property. When the 3d content was more than 25%, the balanceable torque and mixing process energy decreased significantly with the 3d content increased.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
POLYMER SCIENCE SERIES B
·
2023
·Vol. 65
·期 4
·438-449
·
IF 1.2
Caixia Zhao,Yang Sheng,Qin Wang,Zou Guoxiang
Abstract A series of oxybis benzoic aromatic polyesters were prepared by a two-step polymerization method of esterification and polycondensation, using 4,4'-oxybis(benzoic acid) (OBBA) and aliphatic diols with different carbon chain lengths (C2-8) as monomers, and tetrabutyl titanate (TBT) as catalyst. The results showed that the M n of the prepared polyester was between 25350–42040 g/mol, and the polymer dispersity index (PDI) was about 2.0. The results of DSC, WAXD and UV–Visible spectroscopy showed that polyethylene oxybisbenzoic (PEO), polypropylene oxybisbenzoic (PPO), polybutylene oxybisbenzoic (PBO), polypentene oxybisbenzoic (PPeO) and polyhexene oxybisbenzoic (PHO) polyesters were amorphous, and the transmittance at 550 nm ( T 550 ) were 75.0–85.2%, showing good light transmittance. The crystallization rate of polyheptylene oxybisbenzoic (PHeO) and polyoctylene oxybisbenzoic (POO) was slow, which changed from amorphous to semi-crystalline after been placed at room temperature for 10 days, resulting in no transparency. With the increase of carbon chain number of diols in polyester, the T g of polyesters decreased gradually. TGA test results showed that PEO polyester had higher thermal stability ( T 5% = 407.8°C, T d = 441.9°C). The Young’s modulus and tensile strength of the polyester gradually decreased with the increase of the number of diol carbon chains. The elongation at break of polyesters with odd carbon chain diols was low (<20%), while the elongation at break of polyester with even carbon chain diols gradually increased from 4.2 to 1230.2%, which changed from brittle material to ductile material. The rheological properties analysis showed that the aromatic polyesters were typical pseudoplastic fluids.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2025
·
IF 5.2
Decai Lin,Cuiyun Zhang,Miao Zhou,Shicun Jiang,Xinping Wang
The isothermal crystalline morphology of random copolyesters, PTTxGy, prepared by polycondensation of terephthalic acid with mixtures of 1,3-propylene glycol (1,3-PDO, T) and 1,4-cyclohexanedimethanol (1,4-CHDM, G) in different molar ratios, was studied by atomic force microscopy (AFM). The results show that with an increasing molar ratio of the rigid component (G) in the dihydric alcohol, the size of the lamellar crystals in ultrathin films initially increased, followed by the formation of stacked lamellae, where the number of stacking layers progressively increased. The lamellar thickness also increased from 5.6 nm in PTT (0% G) to 12.2 nm in PTT85G15 (15% G) after crystallization at 195 °C. These phenomena are attributed to the inhibition of nucleation in the film with the increase of the G component. Consequently, the crystal size increased, while the crystal density decreased. This further makes the lamellar crystals to nucleate and grow on top of a basal lamellar crystal, forming correlated lamellar crystals. Exclusion of the G component from the crystal results in more tails and loops on the lamellar surface and forms thicker amorphous layers on two sides of the crystal; therefore, the lamellar thickness measured by AFM was increased. The effect of the number of nuclei on the formation of correlated lamellar crystals was further demonstrated through a two-step crystallization procedure. As the number of crystal nuclei increased, the degree of stacking and crystal size decreased until a monolayer of lamellae formed after crystallization at 195 °C. This paper highlights the role of the polymer chemical structure in the resulting crystalline morphology of ultrathin films.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
BIOMASS & BIOENERGY
·
2025
·
IF 5.8
Chunyang Han,Zhen Dong,Yahui Zhang,Haian Xia
Ethylene glycol (EG) and 1,2-propylene glycol (1,2-PG) are very important chemicals that are produced mainly from fossil resources at present. Catalytic hydrogenolysis of biomass (such as cellulose and sugar alcohols) to diols has attracted much attention in recent years. However, compared to sugar alcohols, sugars such as xylose have been scarcely used for the production of EG and PG until now due to their instability and low selectivity of diols. Xylose is an abundant and readily available bio-chemicals that can be produced from the hydrolysis of hemicellulose, but its catalytic hydrogenolysis into diols with high yields remains a great challenge. Herein, bimetallic Ru-Re/CZO(Ce 0.7 Zr 0.3 O 2 ) catalysts were synthesized and used to catalyze the hydrogenolysis of xylose to EG and PG. The nature of the catalysts is thoroughly characterized by XRD, XPS, BET, TEM, etc. It is found that Ru and Re nanoparticles are uniformly distributed on CZO alloy support formed by Ce and Zr. A very high total yield (65.0 %) of EG and 1,2-PG was achieved on the 4 %Ru-1 %Re/CZO catalyst under optimal conditions. Recycling experiments demonstrate that high xylose conversion and diol yields are maintained over four successive cycles under optimal conditions, despite a slight increase in Ru nanoparticle size observed via TEM analysis. The mechanistic study shows that xylose is first isomerized into xylulose, which undergoes retro-aldol cleavage to generate the intermediates, followed by further hydrogenation to EG and 1,2-PG. This work provides a new research avenue for the efficient preparation of diols from xylose.
研究领域:
化学工程
·
生物质转化
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Cheng Zhang,Hongyi Qi,Tianxiao Chang,Yahe Wu,Jiacheng Cao,Mingsen Chen,Yanbin Huang,Wantai Yang
Maleic anhydride (MAH) copolymers have a wide range of applications in various fields. However, the difficulty in obtaining high-molecular-weight (Mw) copolymers through polymerization often limits their potential for application expansion. In this paper, diols were chosen as chain extenders to increase the Mw of MAH copolymers through esterification reactions between anhydride and alcohol, achieving the goal of “chain extension”. As the reaction progressed, the double-end esterification content (DEC) increased and the Mw showed exponential growth accompanied by an increase in gel content. The effects of various reaction parameters, including the temperature, reaction time, types and amounts of diols, polymer concentration, and Mw of raw polymer, on the Mw and gel content of the product were investigated systematically. Furthermore, this method can effectively increase the Mw of various mixed olefin–MAH copolymers. The experimental results demonstrated that the Mw of raw polymers could be increased by up to 70 times (from 18.0 to 1270.8 kg/mol), thereby broadening the polymers’ potential applications.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 131
·期 18
·
IF 1.64
Wen He,Jianwu Lan,Xia Huang,Jiaojiao Shang
A series of high molecular weight poly (butylene succinate) and its copolyester containing rigid imide units were synthesized in this article. The chemical structure and composition of the copolyesters were determined by 1 H NMR spectroscopy and Fourier transform infrared spectroscope (FT-IR). The thermal properties, crystallization behavior and mechanical properties of polymers were investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray diffraction (WAXD) and mechanical testing. The enzymatic degradation was investigated using pancreatic lipase solution. The results showed that the melting temperature ( T m ) of the copolyester decreased with the increment in pyromellitic imide unit content. However, the thermal degradation temperature (5% decomposition temperature) changed little. Meanwhile, the enzymatic degradation rate of poly (butylene succinate) was enhanced. The mechanical properties showed that the tensile strength had a trend of decrease, but the elongation at break was improved with the increment in imide units. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40807.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CLAY SCIENCE
·
2019
·
IF 3.89
Yi Wang,Yanhui Song,Shuang Li,Ting Zhang,Deyi Zhang,Pengran Guo
In order to enhance the loading capacity of palygorskite (Pal) and further understand the relationship between pore size of carrier and thermal properties of mineral-based phase change materials (PCMs), series of three-dimensional palygorskite carriers and corresponding composite PCMs (CPCMs) were fabricated. The morphology, structural characteristics and thermal properties of the support and composite PCMs were determined by various techniques. The effects of support microstructure on the thermo physical properties of CPCMs were also discussed. The results revealed that the isocyanate functionalized palygorskite can be covalently bonded by dihydric alcohol to form three-dimensional Pal-based carrier. The pore diameter of the carrier varies with the chain length of dihydric alcohol. Since covalent bonding and surface functionalization can prevent the agglomeration of palygorskite crystals, thermal energy storage performance of stearic acid/three-dimensional palygorskite is increased by 67.4% to 100.7% within the scope of the study compared with that of stearic acid/palygorskite. The phase change temperature and latent heat of the composite phase change material have a linear correlation with pore size of support. This study is expected to be helpful for designing mineral-based porous carrier and providing guidance for optimizing CPCMs.
研究领域:
材料科学
·
热能工程
·
复合材料
·
储能技术
✓ 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）