APPLIED ENERGY
·
2017
·
IF 7.182
Yi-Tong Wang,Zhen Fang,Xing-Xia Yang
Biodiesel production was catalyzed by a novel magnetic carbonaceous acid (Zr-CMC-SO 3 H@3Fe-C 400 ) with both Brønsted and Lewis sites synthesized by a four-step method: (i) metal (Fe) ion chelation, (ii) calcination, (iii) metal (Zr) ion chelation and embedding, and (iv) sulfonation. It catalyzed the esterification of oleic acid with 97% biodiesel yield, transesterification of high acid value (AV) soybean oil with 95% biodiesel yield, and pretreatment of Jatropha oil with AV reduced from 17.2 to 0.7 mg KOH/g. Biodiesel yields (>90%) at 90 °C for 4 h reaction time were obtained for ten cycles by easy magnetic separation which showed potential practical applications in the field of green production. The synthesized catalyst was characterized with elemental analysis, XRD, ICP-OES, FT-IR, BET, VSM, SEM-EDX, HRTEM, TG-DSC and Boehm titration.
研究领域:
化学工程
·
可再生能源
✓ 已验证
DOI
高影响因子
POLYMER INTERNATIONAL
·
2012
·Vol. 62
·期 10
·1457-1464
·
IF 1.902
Youmei Bao,Jing He,Yuesheng Li
Hyperbranched polyesters with thioether linkages were facilely prepared from methyl 10-undecenoate, a castor oil-derived renewable chemical. The monomer was obtained in excellent yield through thiol–ene click chemistry in the presence of catalytic amounts of photoinitiator under UV irradiation. Subsequent bulk polycondensation via a transesterification process catalyzed by Ti(OBu) 4 , Sb 2 O 3 or Zn(OAc) 2 gave hyperbranched polyesters with high molecular weights and unusual crystalline properties. The degree of branching in the range 0.45 − 0.54 calculated from quantitative 13 C NMR spectroscopy and low inherent viscosities of 0.16 − 0.25 dL g −1 strongly confirmed the hyperbranched structures of the resultant polymers. © 2012 Society of Chemical Industry
研究领域:
材料化学
·
可再生资源化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING & TECHNOLOGY
·
2019
·Vol. 43
·期 3
·403-411
·
IF 2.418
Huan Li,Tian Ma,Zhensheng Shen,An Li,Jie Yang,Dong Xiang,Jiuyi Liu,Shuguang Deng,Yingqiang Sun
1-Butyl-3-methylimidazolium hydrogen sulfate ([Bmim][HSO 4 ]) is utilized to catalyze transesterification of camelina oil with methanol. The major compositions of camelina biodiesel are saturated fatty acid esters (C16:0, C18:0), monounsaturated, and polyunsaturated fatty acid esters (C18:2, C18:3). The effects of reaction temperature, reaction time, M methanol : M Camelina oil , and M [Bmim][HSO4] : M Camelina oil on biodiesel production are investigated in detail, and a general mathematical model is developed to well predict the biodiesel yield. Also, [Bmim][HSO 4 ] is thermally stable to recycle for four times with a high biodiesel yield. The fuel properties of camelina biodiesel are all comparable to the American Society for Testing Materials (ASTM) standards.
研究领域:
能源科学
·
化学工程
✓ 已验证
DOI
高影响因子
NANO
·
2026
·
IF 1.3
Dongliang Liu,Chenghong Liu,Jianxiong Zhang,Zhihua Xu,Chang Xiong,Muhammad Saeed,Yanbo Li,Shengpei Wang
Liquid-blocked phenolic 2-ethylentvl 3-(3,5-di-tert-butyl-4-hydroxphheny)propanoate (EDHP) is commonly utilized as an antioxidant in industrial lubricants to increase the service life of lubricating oil. The conventional homogeneous catalytic transesterification method for preparing EDHP necessitates a significant amount of organic solvents for treating the intermediate, resulting in substantial labor and material costs, ultimately increasing application expenses. Here, a series of porous potassium titanate (K 2 Ti 8 O 1 7 , KTiO) nanoparticles with varying specific surface area (BET) and pore diameter distributions were developed by a simple hydrothermal calcination method for highly efficient and selective catalysis in the transesterification synthesis of EDHP. Transesterification results indicate that Brunauer–Emmett–Teller (BET) significantly impacts the catalytic performance of KTiO, leading to a conversion rate of methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (MDHP) reaching 98.3% and the selectivity reaching 99.70% in the presence of KTiO-400 catalyst at 1 7 5 ∘ C . The transesterification time of heterogeneous catalysis is 2.5 h, which is comparable to that of commercial homogeneous catalysis (tetrabutyl titanate, TBOT), owing to the high BET (182.42 m 2 g − 1 ) of KTiO-400. Current research demonstrates that the use of porous KTiO nanoparticles represents a significant advancement in the field of heterogeneous catalytic organic synthesis and expands the potential applications of nano-titanate in industrial catalysis.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2016
·
IF 5.267
Ming-Jie Chen,Rui-Min Li,Xue-Qin Zhang,Jing Feng,Jin Feng,Chuan-Fu Liu,Qing-Shan Shi
Homogeneous esterification of lignocellulosic agro-forestry wastes is an efficient approach to transform the biomass into value-added biobased materials. However, the application of fatty acid anhydrides or acyl chlorides as esterified reagents would yield equivalent acids which lead to significant decomposition of lignocellulosic biomass. The present study proposed an alternative chemical approach to prepare bioplastics from lignicellulosic biomass. Sugar cane bagasse esters were prepared by transesterification with vinyl esters using 1-ethyl-3-methylimidazolium acetate as duel solvent and activator. Solution-stated NMR studies suggested that the polysacchirides were highly reactive during the homogeneous transesterification. The chemical mechanism of the transesterification was demonstrated to be a carbene mechanism, which subsequently transferred into the intermediate of 2-alkanoyl-dialkylimidazolium. The as-prepared sugar cane bagasse esters were found to be solvable in common solvents. Bioplastic films were prepared by solution casting. Scanning electron microscopy and tensile testing studies showed that the sugar cane bagasse ester films were comparable to those of cellulose fatty esters.
研究领域:
生物质化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Zedong He,Lei Feng,Ju Xie,Hailong Liu,William W. Yu,Jie Zhang
Chemical reactivity will have new traits in system combining organic and silicon compounds. In this paper, the kinetics of melt transesterification of dimethyl terephthalate (DMT) with a siloxane diol of 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane (HP-TMDS) was fitted on the premise of the reaction mechanism obtained by quantum-chemistry calculation. This work reveals that the siloxane diol changes the reaction process and gives the classical transesterification its peculiarity, including more obvious advantage in kinetics for cyclic dimer and limited compatibility between reactant and catalyst. A solution is proposed to solve the problem resulting from the limited compatibility, which can be reference to any similar systems. The obvious advantage in kinetics for cyclic dimer brings a distinct feature in the product composition, which will provide more flexible and effective way to prepare silicon-containing polyesters.
研究领域:
有机化学
·
高分子科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Xiling Niu,Fenfen Wang,Xiaohui Li,Rongchun Zhang,Qiang Wu,Pingchuan Sun
Vitrimers are fascinating thermoset polymers to the industry since they can be recycled and reprocessed without compromising their mechanical strength and solvent resistance. Particularly, transesterification reaction in the epoxy resin (ER) vitrimers usually requires the incorporation of a catalyst, whereas most reports only focused on investigating the catalytic effect of small molecules, such as zinc acetate (Zn(OAc)2) and triazabicyclodecene (TBD). In this work, a polymer catalyst, poly(acrylonitrile-co-zinc methacrylate) (Zn-PAM), was synthesized by the random copolymerization of zinc methacrylate and acrylonitrile, where the transesterification catalysis efficiency of Zn-PAM was systematically investigated and compared to that of Zn(OAc)2 and TBD by temperature-dependent stress relaxation experiments. It was revealed that Zn-PAM has a higher catalysis efficiency than Zn(OAc)2 and TBD under the same loading between Zn2+ and TBD. Besides, only a tiny amount of polymer catalyst is needed to efficiently catalyze the transesterification reaction while in the meantime enhance the mechanical properties of ER.
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
POLYMER
·
2020
·
IF 4.231
Shengdi Yan,Wenqin Lai,Ming Zhang,Guozhang Wu
Catalytic activities of metal laurates with different coordination capabilities and sodium salts with different ligand alkalinities toward the transesterification between isosorbide (ISB)-based polycarbonate (I c C-PC) and bisphenol-A polycarbonate (BPA-PC) are investigated to accelerate asymmetric chain exchange without aggravating chain degradation. Only catalysts capable of direct reaction with PC chains to form metal alkoxide containing active species (PC–O-M) can initiate and thus accelerate chain transesterification . Sodium salts exhibit the highest catalytic activity and can be further improved by complex formation of 15-crown-5, demonstrating the key role played by alkalinity of reactive ligands. Different from weak catalytic selectivity and serious chain scissions by tin-based catalysts, it is found that, for sodium-catalyzed systems, BPA-PC chains prefer to bond to ISB segments in endo position and the high reactivity of sodium-based catalysts not only significantly reduces essential loading but also suppresses chain degradation. We confirm that these differences must arise from whether active PC-O-M acts as a direct nucleophilic attacker or works with coordination process.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING COMMUNICATIONS
·
2019
·
IF 1.431
Lijuan Yang,Hong Yuan,Siyu Wang,Jie He,Ning Yan
In this study, concave carbon microspheres (CCMSs) were synthesized using glucose as the raw material in the presence of an anionic surfactant sodium dodecyl sulfate (SDS) by a hydrothermal method. Sulfonic acid groups (−SO3H) were attached on the CCMSs surfaces by sulfonation using concentrated sulfuric acid, affording a solid acid catalyst (CCMSs catalyst). Scanning electron microscopy (SEM) results revealed that the diameters of the microspheres are 1–3 μm, and the diameters of the concave are 1–2 μm; hence, micron or submicron reaction cells can be formed Furthermore, sulfonation did not change the morphology of the carbon microspheres. N2-BET measurement results revealed that at a hydrothermal temperature and time of 180 °C and 8 h, respectively, and an SDS dosage of 0.10 g, the Brunauer-Emmett-Teller (BET) surface area of CCMSs could reach up to 7.7 m2/g. X–ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) results confirmed that CCMSs are successfully modified by sulfonation. The surface acid amounts of CCMSs before and after sulfonation were 3.7 and 5.6 mmol H+/g, respectively. CCMSs catalyst was used to catalyze the transesterification of waste frying oil, affording fatty acid methyl ester in 93% yield. CCMSs catalyst was used to catalyze the epoxidation of waste frying oil, achieving a double-bond conversion of 79% and a relative epoxy yield of 57%.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
IET Nanodielectrics
·
2026
·Vol. 9
·期 1
·e70035
·
IF 4.3
Wu Fa-Yuan,Li Xiang-qing,Luo Yi-Chen,Chen Shuo,Liu He-Chen
This study investigates the influence of different transesterification catalysts on the performance evolution of degradable epoxy resins under thermal-oxidative ageing. Three resin systems were prepared using triethanolamine (TEOA), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), and zinc acetylacetonate as catalysts, followed by ageing tests at 220°C. The effects of ageing time and catalyst type on the electrical, thermal, mechanical properties and degradation behaviour of the resins were systematically analysed. Results reveal that prolonged ageing causes certain performance degradation, yet the resins still maintain favourable overall properties at the late ageing stage. The V-TEOA system shows the best performance retention after 42 days of ageing, with key indicators as follows: breakdown strength 36.7 kV/mm, dielectric loss factor 0.46%, leakage current 65.34 μA, flexural strength 67.32 MPa and temperature index 170.99°C. Meanwhile, thermal-oxidative ageing markedly weakens the degradation efficiency of the resins, and a distinct core–shell structure is found in the degraded V-TBD system. This work deepens the understanding of ageing behaviours of such resins and supports their practical application in the engineering.
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2025
·
IF 6.3
Ruilong Xu,Feng Zhao,Guanyu Chen,Yiting Jiang,Wei Liu,Shuai Zhao,Lin Li
To improve the toughness of PLA without loss of biodegradability. In this study, a reversible ester exchange network (VEC) based on bio-based materials—epoxidized soybean oil (ESO) and anhydrous citric acid (CA)—was generated in situ during the extrusion molding process of poly(lactic acid) (PLA) via a simple and efficient preparation method. Focusing on the toughening performance of VEC on PLA, it was found that the R-value of VEC (the equivalent ratio of CA carboxyl groups to ESO epoxy groups), catalytic system, polymerization time, and VEC content were the key parameters influencing the mechanical enhancement. The results demonstrated that VEC acted not only as a nucleating agent to promote PLA crystallization but also as a plasticizer facilitating molecular chain mobility. Rheological analysis showed that VEC enhanced the melt strength of PLA and intensified shear thinning behavior, thereby enriching the structural complexity and broadening the processing versatility of PLA-based products. More importantly, PLA and VEC chemically interacted to improve phase compatibility. Notably, the addition of only 5 wt% VEC resulted in the formation of a complete internal toughening network, yielding elongation at break and impact strength values that were 49.1 times and 2.27 times greater, respectively, than those of neat PLA. PLA/VEC waste products can be effectively recycled via re-extrusion. During the recycling and remodeling process, a relatively complete dynamic VEC network is re-established within the composite, with the elongation at break reaching 38.4 times that of neat PLA, indicating significant application potential. PLA/VEC can undergo complete degradation under alkaline conditions within 30 days.
研究领域:
高分子科学
·
材料工程
·
生物降解材料
·
可持续化学
·
塑料加工
✓ 已验证
产品关联
DOI
高影响因子
ENERGY CONVERSION AND MANAGEMENT
·
2018
·
IF 6.377
Xing-Xia Yang,Yi-Tong Wang,Ya-Ting Yang,Er-Zhong Feng,Jia Luo,Fan Zhang,Wen-Jing Yang,Gui-Rong Bao
The transesterification activity of several solid base catalysts in biodiesel production was systematically studied and evaluated at room temperature. Commercialized calcined silicates showed stronger transesterification ability than other commonly-used oxides, and provided considerable biodiesel yields. Biodiesel yield of >96% was obtained for Na 2 SiO 3 catalyst (calcined at 400 °C) at 28 °C within 12 h with methanol/oil molar ratio of 12/1 and catalyst dosage of 5 wt%, and for CaSiO 3 catalyst (calcined at 550 °C) at 28 °C within 24 h with methanol/oil molar ratio of 27/1 and catalyst dosage of 23 wt%. The high activity of Na 2 SiO 3 came from low activation energy of 104.6 kJ/mol and considerable higher pre-exponential factor of 3.73 × 10 15 min −1 , which produced high turnover frequency of 0.234 min −1 at 28 °C. The introduction of CA-O-Si structure in CaSiO 3 resulted in high surface basicity of 0.70 mmol/g and high pre-exponential factor of 3.79 × 10 19 min −1 but high activation energy of 136.4 kJ/mol. The loss of catalyst activity was mainly due to the variation of surface silicate structure during transesterification.
研究领域:
化学工程
·
可再生能源
·
催化化学
✓ 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）