Waste and Biomass Valorization
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2016
·Vol. 8
·期 1
·95-102
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IF 0.915
Zhang Peng,Chang Zhidong,Wang Dongyu,Blamo Benjamin John,Li Wenjun
Biodiesel is an environmentally friendly fuel which can be economically produced by the use of waste culinary oil as raw material and NaOH as catalyst. However, the moisture in waste culinary oil or solid NaOH can affect the distribution of final products. In this paper, the water content of solid NaOH and waste culinary oil were determined to be 4.7 and 1.0 % respectively. A simulated transesterification system of methyl butyrate and n-butanol was catalyzed by anhydrous NaOH which was sintered at 800 °C for 2 h. The moistures in reaction system were imitated by contrived addition of water. Experimental results show that when the water content is 0.25 %, the yield of transesterification achieves the highest, simultaneously, saponification remains at the minimum level. The soybean oil and methanol were investigated as exemplary biodiesel system. The results show that when the water content is 1 %, the yield of biodiesel reaches 98.81 %, which is the highest.
研究领域:
化学工程
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可再生能源
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高影响因子
ULTRASONICS SONOCHEMISTRY
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2017
·
IF 4.218
Guo-Wei Yu,Jing Nie,Lin-Guang Lu,Shen-Peng Wang,Zu-Guang Li,Maw-Rong Lee
Microwave and ultrasound have been demonstrated to be outstanding process intensification techniques for transesterification of oil. According to their mechanisms, simultaneous effects can surely bring about better enhancement than sole microwave or ultrasound. Therefore, this study aimed to investigate the important factors and their suitable levels in the KOH-catalyzed transesterification of soybean oil with methanol by using synergistic assistance of microwave-ultrasound (CAMU). The feasibility of application of CAMU in transesterification of oil was demonstrated. When the dosage of methanol, soybean oil and KOH were 15.4 g, 34.7 g (with methanol-to-oil molar ratio of 12:1) and 1 g, respectively, and the microwave power, ultrasonic power, ultrasonic mode, reaction temperature and reaction time were 700 W, 800 W, 1:0, 65 °C and 6 min, respectively, the transesterification reached 98.0% of yield, being the highest yield among all the results obtained; while by using 600 W of microwave plus stirring instead of CAMU, only 57.4% of yield could be obtained. Compared with other reaction techniques, the transesterification by applying novel CAMU was found to have remarkable advantages. Furthermore, by monitoring the variation of real-time temperature and microwave power during transesterification reactions with different microwave operation time and by taking comparison of the corresponding yield, it was demonstrated that the main reason for the acceleration of microwave-assisted transesterification was the polarization and further activation of reactants caused by microwave irradiation, but not the factor of fast heating.
研究领域:
生物化学工程
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可再生能源
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DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2014
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IF 1.552
Xianfeng Fu,Jianyong Zheng,Xiangxian Ying,Hongde Yan,Zhao Wang
A novel ultraviolet (UV) spectrophotometric method for evaluating lipase transesterification activity in organic solvents is described. The model reaction was lipase-catalyzed transesterification between p -nitrophenyl palmitate (pNPP) and n -butanol in n -hexane at 30 °C. The conversion of pNPP to p -nitrophenol was monitored by measuring UV absorbance changes at 310 nm. Seven commercial lipases were tested using this method, and the results were similar to those obtained using gas chromatography . The UV spectrophotometric method was used to investigate the kinetics of the Lipozyme TL IM-catalyzed reaction of pNPP, and the correlation between synthetic activity and biocatalyst concentration was determined. The method was also used to investigate the Lipozyme TL IM-catalyzed transesterification properties, namely solvent effect, acyl acceptor specificity, alcohol tolerance, optimum reaction temperature, and thermostability.
研究领域:
生物化学
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酶工程
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DOI
高影响因子
RSC Advances
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2017
·Vol. 7
·期 12
·7250-7258
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IF 3.108
Qingqing Guan,Yi Li,Yuan Chen,Yuzhen Shi,Junjie Gu,Bin Li,Rongrong Miao,Qiuling Chen,Ping Ning
Effective solid acid catalysts play a key role to produce high-quality biodiesel through triglyceride transesterification. The present work describes a facile technique for the synthesis of a high-performing sulfonated multi-walled carbon nanotube (S-MWCNTs) solid acid catalyst for fatty acid ethyl ester (biodiesel) production. The results indicated that S-MWCNTs possessed high acidity due to their polycyclic textural matrix. An overall conversion of 97.8% is achieved for triglycerides at 1 h, 150 °C using 3.7 wt% of catalyst in ethanol, outperforming its counterpart catalysts, such as hydrothermal carbonization synthesized sulfonated carbon and metal oxide catalyst WO3/ZrO2. This superior performance is a result of the high acidity that S-MWCNTs possess, stemming from their polycyclic textural matrix. The catalyst was fully characterized by BET, FT-IR, XPS and TEM measurements to understand and evaluate their physical and structural properties. Combining activity and characterization data enables the postulation of the following reaction mechanisms for triglyceride transesterification based on S-MWCNTs:SO3H groups first absorb triglycerides and ethanol through the interaction between the acid sites and the atomic oxygen. The carbonyl carbon was then attacked by the nucleophilic ethanol to produce fatty acidethyl ester (CH3CH2COOR), the final product. Findings from this work provide useful insights on designing effective solid acid catalysts via facile synthesis and regeneration protocol for the transesterification of triglyceride to produce biodiesels.
研究领域:
化学工程
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能源科学
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催化材料
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高影响因子
CHEMOSPHERE
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2022
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IF 8.943
Jia-Hui Chen,Jia-Hui Lu,Xiao-Lu Pu,Li Chen,Yu-Zhong Wang
Flame retardancy and recyclability are two important issues in the research field of thermosets, particularly for epoxy resin (EP) with the biggest market share. It is of great importance, but rarely achievable, to integrate these properties simultaneously into EP. Herein, we report a facile way to prepare intrinsically flame-retardant epoxy vitrimers combining rapid recycling and multiple shape memory effects by introducing dynamic ester-linkages with catalytic transesterification activity into the crosslinking networks of EP. The flame-retardant epoxy vitrimers exhibited high T g (∼110.7 °C), desirable thermal stability and excellent flame retardancy with UL-94 V-0 rating, and high LOI of ∼34%. Also, the value of the peak heat release rate (PHRR) and the total heat release (THR) showed 63% and 32% reduction, respectively. Meanwhile, flame-retardant epoxy vitrimers showed high malleability that could be reprocessed in 15 min at 200 °C without sacrificing the mechanical properties and flame retardancy. Moreover, the dynamic transesterification network allowed flame-retardant EP to access multiple shape memory effect. The design of flame-retardant epoxy vitrimers provide a prime example to foster the cyclic utilization of flame-retardant thermosetting polymers.
研究领域:
材料科学
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高分子化学
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消防安全工程
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DOI
PubMed
高影响因子
FUEL
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2023
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IF 7.4
Zhiwen Ma,Tao Lu,Yali Pan,Yupeng Yuan,Yingqiang Sun
Ionic liquids (ILs) catalyzed in-situ transesterification (IST) of microalgae is a promising strategy to improve biodiesel yield through enhancing cellulose solubility and catalyzing transesterification. Effect of anions of ILs on biodiesel has been widely investigated previously. However, how do cations of ILs affect IST of microalgae is still unclear. On this basis, ILs composed of alkyl-imidazolium cations with different length, 1-ethyl-3-methylimidazolium tetrafluoroborate ([Emim][BF 4 ]), 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF 4 ]), and 1-hexyl-3-methylimidazolium tetrafluoroborate ([Hmim][BF 4 ]) catalyzed IST of microalgae are experimentally and theoretically investigated. The results indicate that increasing alkyl chains of cations weakens interactions of ILs-cellulose, and reduces acidities of ILs, subsequently leads to decrease of cellulose extraction yield and biodiesel yield. Although cellulose extraction yield and biodiesel yield are affected by reaction temperature, dosage of methanol, and MILs: Algae, however, H-bonding interactions of ILs-cellulose and acidities of ILs are still dominate parameters affecting cellulose extraction yield and biodiesel yield, respectively, leading to their unchanged sort under variable reaction conditions as following: [Emim][BF 4 ] > [Bmim][BF 4 ] > [Hmim][BF 4 ]. This work reveals that short alkyl chain of cation is favorable to both cellulose extraction and biodiesel yield, providing theoretical guides for screen and design of benign ILs to further improve biodiesel of in-situ transesterification of microalgae.
研究领域:
化学工程
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生物化学
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可再生能源
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DOI
高影响因子
POLYMER
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2024
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IF 4.1
Pei Zhang,Rulin Yang,Yuzhu Wang,Hongguang Sun,Guangqiang Xu,Qinggang Wang
The chemical recycling of plastics to monomers provides efficient assistance for sustainable development of plastics. For polyglycolide (PGA), it has gained widespread attention to be a highly promising plastic material due to its excellent performance. However, research on the ring-closing depolymerization of PGA has yet to break through. The depolymerization is mainly limited by the challenges brought by high crystallinity and melting point of PGA, and instability of glycolide (GL). In this work, a synergistic transesterification strategy is proposed to achieve efficient depolymerization of PGA to monomer GL. Utilizing the versatile catalyst zinc bis[bis(trimethylsilyl)amide] (Zn(HMDS)2) to promote simultaneous intramolecular and intermolecular transesterification, the random chain scission and back-biting depolymerization is achieved in succession. Therefore, the depolymerization product GL can be obtained in high yield and purity. This strategy will provide new research ideas for the chemical recycling of plastics.
研究领域:
材料科学
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化学工程
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环境科学
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DOI
高影响因子
Sustainable Energy Technologies and Assessments
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2026
·
IF 7.4
Hui Li,Yixuan Zhang,Phumlani Fortune Msomi,Yunpu Wang,Xiaoling Ma
CaO-CNT absorbs 92% broad-spectrum light and rapidly produces localized heat. • Photothermal transesterification delivers efficient energy supply to active sites. • Under optimal conditions, 99.22% biodiesel conversion is achieved at 50 °C. • LCA demonstrates low carbon profile with GWP 2.07 kg CO 2 eq·kg −1 and DFF 28.24 MJ·kg −1 . Transesterification for biodiesel production demands external heat supplied through temperature gradient-driven heating, which limits energy efficiency. Photothermal catalysis offers an alternative route, but reported photothermal catalysts for biodiesel transesterification often suffer from narrow-spectrum light harvesting, strict requirements for monochromatic high-power light sources, and inefficient heat delivery to active sites, which severely restrict their practical application. In this study, a CaO-CNT photothermal catalyst was fabricated via wet impregnation coupled with high-temperature calcination to enable in-situ solar-to-heat conversion and boost catalytic activity. Multiple characterization techniques, including TG/DTG, XRD, XPS, SEM, Raman spectroscopy, N 2 adsorption and desorption, UV-Vis-NIR spectroscopy and infrared thermal imager were carried out, and simulated sunlight from a xenon lamp was used for palm oil photothermal transesterification. The CaO-CNT catalyst exhibited 92% light absorption over 300-2500 nm and rapidly increased its surface temperature from ambient temperature to 70.7 °C within 300 s under an irradiation power density of 14.5 W/g. Compared with conventional water-bath heating, photothermal heating catalyzed by CaO-CNT resulted in higher biodiesel conversions, with improvements of 7.71%, 12.48%, and 9.71% at 46 °C, 50 °C, and 54 °C, respectively. The maximum biodiesel conversion of 99.22% was achieved by photothermal-driven heating with a catalyst loading of 6 wt%, a methanol/oil molar ratio of 10, and an irradiation power density of 15.2 W/g for 2.5 h. Findings from life cycle assessment (LCA) established that the global warming potential (GWP) of this process reached 2.07 kg CO 2 eq·kg −1 , with the depletion of fossil fuel (DFF) amounting to 28.24 MJ·kg −1 . Download: Download high-res image (194KB) Download: Download full-size image
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高影响因子
CATALYSIS LETTERS
·
2026
·Vol. 156
·期 10
·275
·
IF 2.5
Hu Zhoulin,Li Jianwei,Zhang Chuanqi,Guo Wenzhi,Dai Bin,Zhang Chuancai
This study prepared and evaluated hollow spherical (B-Al 2 O 3 ) and needle-like (N-Al 2 O 3 ) alumina catalysts in a fixed-bed reactor for the transesterification of dimethyl oxalate (DMO) with ethanol (EtOH) to produce diethyl oxalate (DEO), using commercial alumina (C-Al 2 O 3 ) as a reference. Experimental results indicated that catalytic activity followed the order B-Al 2 O 3 > N-Al 2 O 3 > C-Al 2 O 3 . At 140 °C and a space velocity of 0.2 h –1 , B-Al 2 O 3 achieved a DMO conversion of 100%, with a DEO selectivity of 84.9% and an ethyl methyl oxalate (EMO) selectivity of 15.1%. The superior performance of B‑Al 2 O 3 originated from its largest specific surface area (202.52 m 2 /g), abundant weak acid‑base sites, and high oxygen vacancies that served as Lewis acid sites, providing more accessible active sites and promoting reactant activation. In situ DRIFTS results suggested a possible nucleophilic substitution pathway for the reaction, involving the replacement of CH 3 O − in DMO by C 2 H 5 O− from EtOH to form DEO. Deactivation studies revealed that coke deposition primarily caused catalyst deactivation; however, catalytic activity could be fully restored after regeneration. This study highlighted the morphological advantages of hollow spherical alumina and elucidated its structure–activity relationship, offering a design strategy for developing efficient catalysts for the green synthesis of DEO. Graphical
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高影响因子
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY
·
2018
·Vol. 95
·期 1
·79-88
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IF 1.601
Ting Zheng,Zhenyu Wu,Qinglong Xie,Meizhen Lu,Fan Xia,Guangquan Wang,Yong Nie,Jianbing Ji
Owing to the decrease of global oil price, development of downstream value-added products is important to biodiesel industry. In this study, we used palmitic acid methyl ester (PAME) as a starting material to produce 2-ethylhexyl palmitate (2-EHP), an environmentally friendly biolubricant product, which was derived from the transesterification of fatty acid methyl esters and long chain fatty alcohols. Conventional synthetic routes of 2-EHP have disadvantages, including high catalyst price, low conversion efficiency, and pollution issues. To solve these problems, in situ transesterification of PAME with 2-ethylhexanol (2-EH) was conducted over unsupported potassium carbonate as heterogeneous catalyst. The optimal reaction temperature, 2-EH to PAME molar ratio, and catalyst to PAME mass ratio were 180 °C, 3:1, and 3.0 wt%, respectively. The PAME conversion reached up to 100% within 1 hour under the optimal conditions. In addition, a kinetic model describing the experimental data over a temperature range of 160–180 °C was developed. The dependence of kinetic rate constant ( k ) on temperature was evaluated, and the activation energy ( E a ) for the transesterification of PAME with 2-EH was calculated to be 57.04 kJ mol −1 .
研究领域:
化学工程
·
环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
·
IF 12.5
Kaiqi Du,Guangpeng Chen,Hao Pan,Liting Fan,Huiping Xu,Wenqiu Su,Shaolong Wan,Wenjing Hong
Base-catalyzed transesterification was studied for PGMEA synthesis avoiding acid and water. • EtONa was identified as the catalyst and its deactivation mechanism was EA Claisen condensation. • In situ formation of sodium PGME can partially suppress catalyst deactivation at low loadings. • 99.90% PGMEA with negligible metal and moisture was achieved by customized rectification. • Process simulation of two-stage distillation shows that electronic-grade PGMEA is achievable. Propylene glycol methyl ether acetate (PGMEA) is an essential electronic-grade solvent in semiconductor manufacturing. However, the conventional esterification route introduces acid and water, requiring extensive purification to meet ultra-stringent quality standards. Herein, an alternative transesterification process with base catalysts that inherently avoids acid and water formation was systematically investigated. Sodium ethoxide (EtONa) exhibited the highest catalytic activity among the bases examined. Catalyst deactivation was traced to EtONa-catalyzed Claisen condensation of ethyl acetate (EA), while the formation of sodium PGME (PGMENa) partially suppressed this effect at low catalyst loadings. Using a customized rectification process, PGMEA with 99.90% purity and negligible metal content was obtained, and process simulation results indicate that electronic-grade purity (99.9999%) is achievable. This work demonstrates a practical and industrially viable route for the production of ultra-high-purity PGMEA.
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DOI
高影响因子
Molecular Catalysis
·
2026
·
IF 4.3
Zhendong Pan,Ying Liu,Yong Li,Yifan Liu,Zifeng Yang
PILs@ZnOx nanocatalyst was constructed via in-situ self-assembly of pyrrolium-based PILs and ZnO, featuring tailored oxygen vacancies for potentially relieving the entrainment phenomenon of reactive distillation, dual alkaline sites and unique interfacial microenvironment to facilitate transesterification. • The catalyst exhibited outstanding activity and good stability for room-temperature synthesis of DMC from CO 2 -derived cyclic carbonate, far superior to metal oxide catalyst. • Multiple characterizations combined with in-situ spectroscopy elucidated the synergistic catalysis of dual basic active sites at the catalyst interface. Pyrrolium-based polymeric ionic liquids-functionalized ZnO nanocatalysts (PILs@ZnO) with an oxygen-vacancy-enriched interface were fabricated via in-situ oxidative polymerization to resolve the entrainment phenomenon in reactive distillation process of producing DMC. The unique interfacial microenvironment effectively modulates the electronic structures and enhances the synergistic catalysis, which could lower the reaction temperature of transesterification between ethylene carbonate and dimethyl carbonate to ambient conditions, and performed the results of EC conversion with 86.7% and DMC selectivity with over than 99.0%. Physicochemical characterizations including FTIR, XRD, XPS and HRTEM were combined with in-situ FTIR and NMR to reveal the structure-activity relationship and further proposed its probably real-time catalytic process. At room temperature, the designed PILs@ZnO x catalyst behaved multiple functional active sites, including strongly basic OH - , pyrrolium-N + cations and Lewis-basic ZnO nanoparticles with a newly constructed oxygen-vacancy microelectronic interface to potentially relieve the entrainment phenomenon in reactive distillation process of producing DMC. Benefiting from the synergistic effect of these multifunctional moieties, PILs@ZnO x exhibits outstanding catalytic performance for the synthesis of DMC from cyclic carbonate. Its catalytic activity is far superior to the pristine ZnO, pure PPY + OH - , and other corresponding PILs-supported metal oxide (PPY + OH - @MgO, PPY + OH - @Al 2 O 3 , PPY + OH - @CaO and PPY + OH - @ZrO 2 ). Download: Download high-res image (327KB) Download: Download full-size image
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高影响因子
危险品化学品经营许可证（带存储）