Reaction Kinetics Mechanisms and Catalysis
·
2021
·Vol. 133
·期 1
·191-208
·
IF 2.081
Wang Jianye,Liu Haifeng,Chen Zhonghui,Sun Yifeng,Wang Song
Waste crayfish shell powder was utilized to prepare a series of solid base catalyst for the transesterification of glycerol with dimethyl carbonate to synthesize glycerol carbonate. Thermal decomposition behavior of waste crayfish shell powder was investigated by thermogravimetric analysis (TGA) and the different catalysts prepared at different calcinations temperature were characterized using FESEM, XRD, FTIR, BET techniques. It was clearly confirmed that the catalyst generated by the calcination of waste crayfish shell at 800 °C exhibited excellent catalytic activity, 98.7% glycerol conversion and 95.3% glycerol carbonate yield were obtained under mild reaction conditions such as 90 min of reaction time, 1:6 molar ratio of glycerol to dimethyl carbonate, 4 wt% of catalyst loading and 75 °C of reaction temperature.
研究领域:
化学工程
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催化
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绿色化学
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材料科学
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高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 8
·e202203952
·
IF 2.1
Pinmei Yan,Xin Zhang,Yuanyuan Huang,Gengwei Liu,Peng Liu,Chenjie Li,Pengbin Pan,Yuangen Yao
Graphical After desilication, the catalyst structure remained unchanged, the pore size increased, the number of mesoporous pores increased, the specific surface area increased, the alkalinity increases, and the strong acid site disappears. After oxides loading, medium strong alkalinity and medium strong acidity increased further. The higher the base strength, the higher the negative charge on EtO δ− , to facilitate the reaction. Ethyl methyl carbonate (EMC) is the product of the partial transesterification of dimethyl carbonate (DMC) with ethanol (EtOH). How to modulate the catalyst with suitable acidity and alkalinity is of key importance for achieving both high activity and selectivity toward EMC. Herein, an Mg−Zn−P/AT-ZSM-5 catalyst with moderate basicity and moderate acidity was intelligently designed by the co-doping of Mg−Zn−P after the desilication of ZSM-5. Under the optimized reaction conditions, the EtOH conversion can reach 99.1 % with a high EMC selectivity of 96.3 %. Based on the results of multiple characterizations, the enhanced EtOH conversion and high EMC selectivity should be attributed to the well dispersed supported metal species, and enhanced metal-support interactions, especially the suitable surface acidity and alkalinity property of the catalyst. Such work provides a more reasonable design strategy for the preparation of a catalyst used for the transesterification reaction of DMC and EtOH to selectively produce high-valued EMC.
研究领域:
化学工程
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催化反应
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Xiangli Gao,Huan Liu,Jianbo Shuai,Junmeng Zhao,Guowen Zhou,Quanbo Huang,Hao Ling,Wenjiao Ge,Xiaohui Wang
Cellulose acetate (CA) is one of the most important cellulose plastics that has demonstrated extensive applications in many areas. In search of a more sustainable and efficient way to prepare CA, we synthesized a novel ionic liquid , [DBUC 8 ]Cl, based on the commonly used catalyst DBU (1,8-diazabicyclo[5.4.0]undecyquin-7-ene) in a simple manner. [DBUC 8 ]Cl can dissolve cellulose more efficiently than the same type of imidazolyl ionic liquid, owing to the stronger alkalinity of DBU. It is noteworthy that highly substituted CA (DS = 2.82) was successfully synthesized via transesterification with alkenyl ester under mild conditions (80 °C, 40 min) without the addition of a catalyst in this solvent, which is superior to most of the reported work. Furthermore, we confirmed that the synthesized CA had good thermoplasticity, and a transparent cellulose acetate film (CAF) was obtained by hot pressing with a small amount of glycerol. Therefore, we propose a new DBU-derived ionic liquid, which may serve as a versatile platform system for producing cellulose-derived bioplastics more sustainably and efficiently.
研究领域:
化学工程
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材料科学
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DOI
PubMed
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2023
·
IF 3.4
Liwen Shu,Xin Zheng,Shuhua Qi,Shuizhi Lin,Yinghua Lu,Chuanyi Yao,Xueping Ling
Docosahexaenoic acid (DHA) enriched with phospholipids (PLs) (DHA-PLs) is a type of structured PL with good physicochemical and nutritional properties. Compared to PLs and DHA, DHA-PLs has higher bioavailability and structural stability and many nutritional benefits. To improve the enzymatic synthesis of DHA-PLs, this study investigated the preparation of phosphatidylcholine (PC) enriched with DHA (DHA-PC) via enzymatic transesterification of algal oil, which is rich in DHA-triglycerides, using immobilized Candida antarctica lipase B (CALB). The optimized reaction system incorporated 31.2% DHA into the acyl chain of PC and converted 43.6% PC to DHA-PC within 72 h at 50 °C, 1:8 PC: algal oil mass ratio, 25% enzyme load (based on total substrate mass), and 0.02 g/mL molecular sieve concentration. Consequently, the side reactions of PC hydrolysis were effectively suppressed and products with high PC content (74.8%) were produced. Molecular structure analysis showed that exogenous DHA was specifically incorporated into the sn-1 site of the PC by immobilized CALB. Furthermore, the evaluation of reusability with eight cycles showed that the immobilized CALB had good operational stability in the present reaction system. Collectively, this study demonstrated the applicability of immobilized CALB as a biocatalyst for synthesizing DHA-PC and provided an improved enzyme-catalyzed method for future DHA-PL synthesis.
研究领域:
食品科学
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生物化学
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PubMed
高影响因子
FUEL
·
2025
·
IF 7.5
Tao Wang,Xiqing Wang,Tianshu Liu,Yujie Fu
Realizing high catalytic efficiency and stability always be the core guiding principle and continuous optimization in industrial production. Fatty Acid Methyl Esters (FAMEs) are a key component of biodiesel, serving as a renewable, environmentally friendly alternative to conventional petroleum-based diesel fuel. In this study, a series of novel Brønsted acidic cellulose-based ionic liquids (PCM-ILs) were successfully prepared using cellulose as the raw material through chemical grafting and ionic bonding. These PCM-ILs were first applied to catalyze the transesterification of Pistacia chinensis Bunge seed oil for FAMEs production. PCM-ILs can be tailored by varying anions. Under optimal conditions—methanol/oil ratio (10:1), catalyst (10 wt%), temperature (80 °C), and time (6 h)—the FAME yield reached 98.6 %. In addition, the conversion yield remained above 85 % after the prepared catalyst be recycled for six times. Thus, the development of this straightforward and economically viable cellulose-based assembly opens up innovative avenues for the design of high-performance biocatalysts suitable for industrial applications.
研究领域:
化学工程
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可再生资源技术
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绿色化学
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高影响因子
JOURNAL OF DAIRY SCIENCE
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2024
·
IF 3.7
Huaying Zhong,Jing Jin,Qi Zhou,Yufei Zhang,Mingming Zheng
ABSTRACT Despite considerable research efforts, lipase catalysis in a fluid milk system with aqueous multi-component mixtures containing multiple microphases, remains challenging. Pickering interfacial biocatalysis (PIB) platforms are typically fabricated with organic solvents/lipids and water. Whether a PIB with excellent catalytic performance can be constructed in complex milk mixtures remains unknown. Here, we challenged PIB with skim milk, and a small amount of flaxseed oil, and phytosterols as a model system for transesterification and lipolysis to enhance quality and flavor. The amino-modified mesoporous silica spheres (MSS-N) were employed as an emulsifier and carrier of lipase AYS (AYS@MSS-N). The conversion of phytosterol esters reached 75.5% at 1.5 h and prepared phytosterol ester-fortified milk with a content of 1.0 g/100 mL. The relative conversion rate remained above 70% after 6 cycles. In addition, the fortified milk showed an intensified and favorable effect on sensory traits through volatile flavor composition analysis. The findings provide a versatile alternative for PIB applications in complex environments, i.e., milk, which might inspire a new bioprocess strategy for dairy products.
研究领域:
食品科学
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生物催化
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乳品技术
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酶工程
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风味化学
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PubMed
高影响因子
CATALYSIS LETTERS
·
2017
·Vol. 148
·期 1
·144-153
·
IF 2.799
Liu Yong,Liu Weihua,Shao Xiaonan,Wang Jianhong,Li Xiying,Zhang Haiyan
Abstract In this work, dicationic acidic heteropolyanion-based ionic liquids were synthesized, and used in transesterification reaction of methyl acetate with isooctyl alcohol for producing isooctyl acetate. Compared with H 2 SO 4 , and H 3 PW 12 O 40 , [Bis-BsImB][HPW 12 O 40 ] and [Bis-Bs-DABCO][HPW 12 O 40 ] shown excellent catalytic performance. The reaction kinetics and chemical equilibrium of the transesterification catalyzed by [Bis-BsImB][HPW 12 O 40 ] and [Bis-Bs-DABCO][HPW 12 O 40 ] were investigated. The effects of reaction temperature, initial reactant molar ratio, and catalyst concentration on the kinetics were studied in detail. The kinetic data were successfully correlated by a pseudohomogeneous model in the temperature range of 328.15 − 343.15 K. The simulation values obtained by the kinetic model were in good agreement with the experimental data. Moreover, [Bis-BsImB][HPW 12 O 40 ] and [Bis-Bs-DABCO][HPW 12 O 40 ] could be easily recovered and reused five times without any obvious decrease in catalytic activity. Graphical Abstract
研究领域:
化学工程
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催化科学
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高影响因子
RENEWABLE ENERGY
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2022
·
IF 8.634
Xiu Gao,Chao Chen,Wenlu Zhang,Yanping Hong,Chunrong Wang,Guoqiang Wu
A series of sulfated TiO 2 supported Mo ( x Mo/1.5ST) catalysts were synthesized successfully and evaluated for the transesterification of Jatropha seed oil (JO) to biodiesel. Extensive characterization exhibits that the well dispersed Mo oxide species, with Mo 6+ and Mo 5+ oxidation states, were formed on the surface of the sulfated TiO 2 . The results indicate the presence of many sulfates species leads to the reduction of Mo 6+ species to Mo 5+ species. Furthermore, the catalytic activity of the x Mo/1.5ST catalysts gradually increases with the increase of Mo-loading, although the sulfates content and the total acid intensity decrease. The transesterification process was fully investigated, and the 10Mo/1.5ST shows the highest yield of biodiesel of up to 97.42%. Additionally, the possible mechanism for the JO transesterification over Mo/1.5ST was described, and the fuel properties of the as-synthesized biodiesel conformed to the current international standards.
研究领域:
化学工程
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可再生能源
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DOI
高影响因子
CATALYSIS LETTERS
·
2026
·Vol. 156
·期 3
·76
·
IF 2.5
Khan Khyrullah,Wang Wei,Chang Zhidong,Dong Bin
The innovation for highly effective solid acid catalysts that resist impurities is crucial for enhancing sustainable esterification and transesterification processes, which are vital for biofuel production and green chemistry. In this work, tungsten-modified sulfated titania (WO₃/SO₄ 2 ⁻/TiO₂) catalyst was prepared through the impregnation method and subsequently calcined at 550 °C to assess the impact of tungsten impurity on its structural and catalytic properties. The catalyst was characterized through FT-IR, XRD, NH 3 -TPD, and BET surface area analysis. These analyses revealed that the presence of sulfate and tungsten species inhibited TiO₂ crystallization, improving the textural properties and increasing surface acidity. The 5 wt.% WO₃/SO₄ 2 ⁻/TiO₂ catalyst demonstrated the largest surface area (35.99 m 2 /g) and total acidity (1.20 mmol NH₃/g). This catalyst achieved 86.4% conversion in the reaction of transesterification of ethyl acetate and n-butanol at 100 °C for 3 h. The enhanced catalytic performance and selectivity were attributed to the synergistic interaction between WO₃ and SO₄ 2 ⁻, resulting in the formation of Lewis-Bronsted acid sites. This study provides important insights into how tungsten affects the structure and acidity of sulfated titania, which could guide the design of more efficient, impurity-tolerant solid acid catalysts for environmentally sustainable chemical processes. Graphical
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高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2026
·
IF 5.1
Peixin Hong,Fengyue Yin,Rongkai Cui,Yongsheng Lin,Xiaoyan Chen,Ting Qiu,Jie Chen
Sec -butyl alcohol (SBA) is a crucial chemical intermediate and solvent in organic synthesis. The transesterification of sec -butyl acetate (SBAC) with methanol (MeOH) is a key SBA production process due to straightforward reaction conditions and raw materials easily available, but conventional catalysts suffer from high corrosivity and poor recyclability, increasing costs. Herein, we report a series of novel heterogeneous catalysts of TEOS-[Ch][Im]- x with differential loading amount of choline imidazolate ([Ch][Im]) supported on SiO 2 . [Ch][Im], for the first time, is employed not only as a basic catalyst to facilitate the formation of SiO 2 , but also as a catalytic moiety immobilized on the SiO 2 matrix via H-O hydrogen bonds, thus enabling the fabrication of efficient SiO 2 -based catalysts through a one-pot reaction. By optimization of catalytic conditions for optimal catalyst TEOS-[Ch][[Im]-12, over 50% SBAC conversion is achieved in 60 min, and the conversion rate reaches 61.58% under the reaction temperature of 67 ℃ , nMeOH: nSBAC = 8.8:1, and catalyst dosage 9 wt% conditions after response surface methodology (RSM) optimization. More importantly, the catalyst exhibits excellent reusability and cycling stability without any noticeable deactivation over five consecutive reaction cycles. Density functional theory (DFT) calculations and in situ diffuse reflectance infrared Fourier transform spectroscopy ( in situ DRIFTs) results further confirm that the functionalized [Im] − anions could activate methanol to form the key adsorbed CH 3 O* intermediate, which then undergoes a nucleophilic reaction with SBAC to yield SBA. This facile synthetic strategy thus endows the catalyst with considerable application potential for green catalytic transesterification processes.
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高影响因子
FOOD CHEMISTRY
·
2026
·
IF 10.4
Hongli Chao,Jing Wang,Yi Wang,Jing Tian,Yi Yang
Flavor esters are extensively used in food and cosmetic industries, yet their sustainable production remains challenging. This study developed a lipase bioreactor through artificial antibody-antigen-mediated immobilization for biocatalytic flavor ester synthesis via transesterification. Artificial antigens were prepared by lipase modification with p -nitrobenzaldehyde, while artificial antibodies were synthesized using 2-(4-nitrophenyl)-1,3-dioxolane (acetal-protected p -nitrobenzaldehyde analogue) as template molecules. These components self-assembled into immobilized lipase with 82.24 ± 0.13% immobilization efficiency, 17.59 ± 0.12 mg/g capacity, and 8.81 ± 0.27 U/mg specific activity. Integrating molecular simulations with acyl donor screening, the bioreactor achieved 97.18 ± 0.93% yield for cinnamyl acetate synthesis from cinnamyl alcohol and vinyl acetate. The system demonstrated exceptional continuous catalysis and scalability, confirming industrial translation potential. Successful synthesis of cinnamyl butyrate (86.25 ± 3.34%) and benzyl acetate (90.68 ± 2.25%) further established its versatility as a platform for diverse flavor ester production.
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高影响因子
DYES AND PIGMENTS
·
2020
·
IF 4.613
Zengfang Huang,Yali Chen,Chaoyue Zhou,Ke Wang,Xiaobo Liu,Liucheng Mao,Jinying Yuan,Lei Tao,Yen Wei
Recently, various AIE-based materials with new characteristics and functions have been developing for different fields. Many chiral polymers are attracting the research interests for the new multifunctional materials in biomedicine, chiral recognition, etc. In this work, novel AIE copolymers with chirality activity were successfully fabricated for the first time. Firstly, a new fluorescent monomer (R)-THM with AIE effect and chirality activity was firstly synthesized by Suzuki reaction and enzymatic transesterification reaction. The quantum yield of (R)-THM increased to 0.643 from 0.100 of its substrate TBP with remarkable red-shift of emission spectra , which was consistent with their quantum chemical calculations of HOMO and LUMO situations, and its specific optical rotation [ α ] D 25 °C was about −9.67°. Subsequently, a series of chiral AIE copolymers of PEG-(R)-THM1 and PEG-(R)-THM2 were prepared via RAFT polymerization of (R)-THM and PEGMA with different feeding ratios. Their molecular weights were about 2.0 × 10 4 g/mol with narrow polydispersity index (PDI), and the kinetics analysis presented a pseudo-first-order linear procedure. For the molar 24.2%–32.3% feeding ratio of (R)-THM, the actual fraction of (R)-THM in the copolymers PEG-(R)-THM1 and PEG-(R)-THM2 was respectively about 22.3% and 30.2%, and the [ α ] D 25 °C value of copolymers PEG-(R)-THM1 and PEG-(R)-THM2 was about −2.51° and −3.74°. The amphiphilic structure of the obtained PEG-(R)-THM make them be easily dispersed in water solution and tend to self-assemble into fluorescent organic nanoparticles (FONs) with 100–150 nm diameter by TEM , and their maximum emission wavelength presented at 495 nm with obvious AIE effect. Moreover, the PEG-(R)-THM FONs had good biological compatibility, desirable low cytotoxicity and good cells absorption effect, which showed the great potential in bioimaging application.
研究领域:
高分子化学
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材料科学
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生物医学工程
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荧光材料
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纳米技术
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手性识别
·
生物成像
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DOI
高影响因子
危险品化学品经营许可证（带存储）