855687-99-9Relevant academic research and scientific papers
Chemicals from biomass: Synthesis of glycerol carbonate by transesterification and carbonylation with urea with hydrotalcite catalysts. The role of acid-base pairs
Climent, Maria J.,Corma, Avelino,De Frutos, Pilar,Iborra, Sara,Noy, Maria,Velty, Alexandra,Concepcion, Patricia
, p. 140 - 149 (2010)
Synthesis of glycerol carbonate has been performed by transesterification of ethylene carbonate with glycerol catalyzed by basic oxides (MgO, and CaO), and mixed oxides (Al/Mg, Al/Li) derived from hydrotalcites. The results showed that the optimum catalyst in terms of activity and selectivity is a strong basic Al/Ca-mixed oxide (AlCaMO) which is able to catalyze the reaction at low temperature (35 °C), and low catalyst loading (0.5 wt%) giving high glycerol conversions with 98% selectivity to glycerol carbonate. When the synthesis of glycerol carbonate was carried out by carbonylation of glycerol with urea, the results showed that balanced bifunctional acid-base catalysts where the Lewis acid activates the carbonyl of the urea and the conjugated basic site activates the hydroxyl group of the glycerol were the most active and selective catalysts.
Investigation of glycerolysis of urea over various ZnMeO (Me = Co, Cr, and Fe) mixed oxide catalysts
Nguyen-Phu, Huy,Do, Lien Thi,Shin, Eun Woo
, p. 80 - 87 (2019/09/30)
In this study, we investigated the glycerolysis of urea over various ZnMeO (Me = Co, Cr, and Fe) mixed oxide catalysts. ZnMeO mixed oxide catalysts were prepared by a co-precipitation method for two Zn/Me ratios, resulting in Zn-rich mixed oxide (Zn2MeO) and Zn-poor mixed oxide (ZnMe2O). In the glycerolysis of urea, the Zn2MeO catalysts exhibited higher glycerol conversion and glycerol carbonate yields than the ZnMe2O catalysts due to the predominance of homogeneous catalysis through Zn isocyanate (NCO) complexes from the Zn2MeO catalysts. Specifically, Zn2CrO was the best catalyst, with the highest yield of glycerol carbonate. Fourier transform infrared (FT-IR) and thermogravimetric analysis (TGA) results of the spent catalysts clearly demonstrated the dominant formation of a solid Zn NCO complex over the spent Zn2CrO catalyst, a unique feature indicating that the better catalytic performance of Zn2CrO was due to the additional heterogeneous reaction route through the solid Zn NCO complex.
Solvent-Free Production of Glycerol Carbonate from Bioglycerol with Urea Over Nanostructured Promoted SnO2 Catalysts
Mallesham, Baithy,Rangaswamy, Agolu,Rao, Bolla Govinda,Rao, Tumula Venkateshwar,Reddy, Benjaram M.
, p. 3626 - 3641 (2020/05/19)
Abstract: In this study nanostructured MoO3 and WO3 promoted SnO2 solid acid catalysts were explored for the production of glycerol carbonate via carbonylation of bioglycerol with urea. The investigated reference SnO2 and promoted catalysts were synthesized by fusion and wet-impregnation methods, respectively. The physicochemical properties of the prepared catalysts were thoroughly analyzed by XRD, Raman, BET surface area, TEM, FTIR, pyridine adsorbed FTIR, NH3-TPD, and XPS techniques. It was found from the characterization studies that integration of SnO2 with MoO3 and WO3 promoters leads to remarkable structural, textural, and acidic properties. Especially, a high quantity of acidic sites were observed over the MoO3/SnO2 catalyst (~ 81.45?μmol?g?1) followed by WO3/SnO2 (61.81?μmol?g?1) and pure SnO2 (46.47?μmol?g?1), which played a key role in the carbonylation of bioglycerol with urea. The BET specific surface area and oxygen vacancies of SnO2 were significantly enhanced after the addition of MoO3 and WO3 promoters. TEM images revealed the formation of nanosized particles with a diameter of around 5–25?nm for the synthesized catalysts. The MoO3/SnO2 catalyst exhibited a high conversion and selectivity towards glycerol carbonate in comparison to other catalysts. The observed better performance is attributed to unique properties of MoO3/SnO2 catalyst including smaller crystallite size, high specific surface area, abundant oxygen vacancies, and more number of acidic sites. This catalyst also exhibited remarkable stability with no significant loss of activity in the recycling experiments. Graphic Abstract: Nanostructured MoO3/SnO2 solid acid catalyst exhibited an excellent catalytic activity and a high selectivity to glycerol carbonate in the carbonylation of bioglycerol with urea under solvent-free and mild conditions.[Figure not available: see fulltext.]
Cu-Mn composite oxides: Highly efficient and reusable acid-base catalysts for the carbonylation reaction of glycerol with urea
Luo, Wei,Sun, Lei,Yang, Yue,Chen, Yanqiu,Zhou, Zhou,Liu, Junhua,Wang, Fang
, p. 6468 - 6477 (2019/01/03)
A series of Cu-Mn composite oxides were prepared by co-precipitation. Interestingly, catalysts with varied Cu/Mn molar ratios showed different catalytic performances for glycerol carbonylation. The physicochemical properties of the catalysts are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, temperature-programmed desorption (TPD) of CO2 and NH3 and temperature-programmed reduction (H2-TPR) technology. The results showed that the Cu1.4Mn1.6O4 crystal phase is the active component of the catalysts for the carbonylation of glycerol, this phase can effectively provide Mn4+ and lattice oxygen (O2-), and the existence of the Mn4+-O2- Lewis acid-base pair can promote the formation of glycerol carbonate. Various reaction parameters, such as reaction temperature, time, the molar ratio of glycerol to urea and the amount of catalysts, are studied. Under optimizing reaction conditions, the conversion of glycerol is 91.0% with 99.1% glycerol carbonate selectivity.
Heterometallic metal-organic framework-templated synthesis of porous Co3O4/ZnO nanocage catalysts for the carbonylation of glycerol
Lü, Yinyun,Jiang, Yating,Zhou, Qi,Li, Yunmei,Chen, Luning,Kuang, Qin,Xie, Zhaoxiong,Zheng, Lansun
, p. 93 - 100 (2017/09/08)
The efficient synthesis of glycerol carbonate (GLC) has recently received great attention due to its significance in reducing excess glycerol in biodiesel production as well as its promising applications in several industrial fields. However, the achievement of high conversion and high selectivity of GLC from glycerol in heterogeneous catalytic processes remains a challenge due to the absence of high-performance solid catalysts. Herein, highly porous nanocage catalysts composed of well-mixed Co3O4 and ZnO nanocrystals were successfully fabricated via a facile heterometallic metal-organic framework (MOF)-templated synthetic route. Benefiting from a high porosity and the synergistic effect between Co3O4 and ZnO, the as-prepared composite catalysts exhibited a significantly enhanced production efficiency of GLC in the carbonylation reaction of glycerol with urea compared to the single-component counterparts. The yield of GLC over the Co50Zn50-350 catalyst reached 85.2%, with 93.3% conversion and near 91% GLC selectivity, and this catalytic performance was superior to that over most heterogeneous catalysts. More importantly, the proposed templated synthetic strategy of heterometallic MOFs facilitates the regulation of catalyst composition and surface structure and can therefore be potentially extended in the tailoring of other metal oxide composite catalysts.
Method for preparing high-added-value chemical product through catalysis of glycerin
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Paragraph 0046; 0047; 0056, (2017/03/21)
The invention discloses a method for preparing a high-added-value chemical product through catalysis of glycerin. According to the synthesis method, the fact that activated glycerin is converted into a high-added-value glycerin derivative is taken as a target, activating reaction is carried out in a hydroxyl functionalized ionic liquid system, and glycerin conversion rate data is obtained through a nuclear magnetic characterization means, so that the activation degree of glycerin is evaluated. The preparation method provided by the invention is simple and mild in reaction conditions and replaces a conventional method taking metal as a catalyst; since an ionic liquid catalytic reaction system is used, so that good environment friendliness and repeatability are realized, an ionic liquid preparation process is environment-friendly and good atom economy is realized.
Formation of glycerol carbonate from glycerol and urea catalysed by metal monoglycerolates
Turney, Terence W.,Patti, Antonio,Gates, Will,Shaheen, Uzma,Kulasegaram, Sanjitha
, p. 1925 - 1931 (2013/09/24)
Polymeric monoglycerolate complexes of zinc and cobalt can act as homogeneous catalysts for the one-pot synthesis of glycerol carbonate from glycerol and urea. Effects of reaction temperature, time and glycerol to urea molar ratios on glycerol carbonate s
Synthesis of glycerol carbonate from glycerol and urea with gold-based catalysts
Hammond, Ceri,Lopez-Sanchez, Jose A.,Hasbi Ab Rahim, Mohd,Dimitratos, Nikolaos,Jenkins, Robert L.,Carley, Albert F.,He, Qian,Kiely, Christopher J.,Knight, David W.,Hutchings, Graham J.
scheme or table, p. 3927 - 3937 (2011/06/18)
The reaction of glycerol with urea to form glycerol carbonate is mostly reported in the patent literature and to date there have been very few fundamental studies of the reaction mechanism. Furthermore, most previous studies have involved homogeneous catalysts whereas the identification of heterogeneous catalysts for this reaction would be highly beneficial. This is a very attractive reaction that utilises two inexpensive and readily available raw materials in a chemical cycle that overall, results in the chemical fixation of CO2. This reaction also provides a route to up-grade waste glycerol produced in large quantities during the production of biodiesel. Previous reports are largely based on the utilisation of high concentrations of metal sulfates or oxides, which suffer from low intrinsic activity and selectivity. We have identified heterogeneous catalysts based on gallium, zinc, and gold supported on a range of oxides and the zeolite ZSM-5, which facilitate this reaction. The addition of each component to ZSM-5 leads to an increase in the reaction yield towards glycerol carbonate, but supported gold catalysts display the highest activity. For gold-based catalysts, MgO is the support of choice. Catalysts have been characterised by XRD, TEM, STEM and XPS, and the reaction has been studied with time-on-line analysis of products via a combination of FT-IR spectroscopy, HPLC, 13C NMR and GC-MS analysis to evaluate the reaction pathway. Our proposed mechanism suggests that glycerol carbonate forms via the cyclization of a 2,3-dihydroxypropyl carbamate and that a subsequent reaction of glycerol carbonate with urea yields the carbamate of glycerol carbonate. Stability and reactivity studies indicate that consecutive reactions of glycerol carbonate can limit the selectivity achieved and reaction conditions can be selected to avoid this. The effect of the catalyst in the proposed mechanism is discussed.
