931-40-8Relevant articles and documents
Catalytic performance of functionalized IRMOF-3 for the synthesis of glycerol carbonate from glycerol and urea
Lee, Sun-Do,Park, Gyung-Ah,Kim, Dong-Woo,Park, Dae-Won
, p. 4551 - 4556 (2014)
A functionalized isoreticular metal organic framework material, F-IRMOF-3, having a quaternary ammonium group was prepared by fast precipitation and solvothermal method. The synthesized MOFs exhibited good catalytic performance in the synthesis of glycerol carbonate (GC) from glycerol and urea. F-IRMOF-3 having a larger alkyl chain structure and a more nucleophilic counter anion than the synthesized congeners, exhibited better reactivity in the synthesis of GC. The introduction of a ZnO defect into the F-IRMOF-3 structure by fast precipitation was more advantageous for the glycerolysis of urea than the conventional solvothermal method because of the incorporation of acid-base bifunctional active sites by the former method. The effects of reaction parameters such as temperature, reaction time, catalyst loading, and degree of vacuum on the reactivity were also investigated. The F-IRMOF-3 catalyst can be easily recovered and reused without considerable loss of its initial activity. Copyright
Enzymatic processing of renewable glycerol into value-added glycerol carbonate
Cushing, Kerri A.,Peretti, Steven W.
, p. 18596 - 18604 (2013)
Increased production of biodiesel has led to excess glycerol production worldwide, which has resulted in a significant drop in glycerol prices. Glycerol carbonate is a multifunctional compound used as chemical intermediates, solvents, additives and monomers. In this study, the enzymatic synthesis of glycerol carbonate from glycerol and a dialkyl carbonate was investigated. Glycerol carbonate was formed when reacting glycerol with dimethyl carbonate, diethyl carbonate or dibutyl carbonate in the presence of Candida antarctica lipase B (Novozym 435), using tert-butanol as a solvent. Nearly 100% glycerol conversion was reached after 12 h, with glycerol carbonate being the primary product. The effects of reaction parameters including solvent choice and biocatalyst loading were also examined. The highest activity was found at restricted water conditions and when using tert-butanol as a solvent.
Transesterification of Glycerol to Glycerol Carbonate Using KF/Al 2O3 Catalyst: The Role of Support and Basicity
Sandesh, Swetha,Shanbhag, Ganapati V.,Halgeri
, p. 1226 - 1234 (2013)
Glycerol carbonate was synthesized by transesterification of glycerol with dimethyl carbonate using KF supported catalyst. KF was impregnated on various oxides and non-oxide supports like Al2O3, SiO2, ZnO, ZrO2,
Design of a technical Mg-Al mixed oxide catalyst for the continuous manufacture of glycerol carbonate
Lari,De Moura,Weimann,Mitchell,Mondelli,Pérez-Ramírez
, p. 16200 - 16211 (2017)
The availability of a heterogeneous catalyst, which contains cheap and abundant elements, has a scalable synthesis, is highly active and stable, retains its performance upon shaping into a technical form and can be operated in continuous mode, would pave the way for a more ecological and economical production of glycerol carbonate from glycerol and urea. Here, we show that a mixed oxide of Mg and Al is a promising active phase for this reaction. The solid comprises widely available and non-toxic metals, is easily obtained through the thermal decomposition of a hydrotalcite-like material and can almost match the product yield of state-of-the-art Zn-based catalysts, while displaying an outstanding resistance against leaching, which causes the rapid dissolution of the latter. In-depth characterisation uncovered that Lewis-basic centres are crucial to activate glycerol through dehydrogenation. Their concentration was maximised by optimising the composition and calcination temperature of the precursor, thus reaching up to 60% glycerol carbonate yield. Millimeter-sized extrudates featuring comparable basic properties to the powder sample, a well-developed meso- and macroporosity and high mechanical stability are obtained using a natural clay, bentonite, as a binder and thermally activating the hydrotalcite only after shaping. Upon testing in a continuous reactor under tuned conditions of temperature and pressure and in the presence of an aprotic solvent, the system attains the same glycerol yield as in the batch tests. During 100 h on stream, its activity decreases by 20% due to fouling, but can be fully restored upon burning-off of the carbonaceous deposits. This work discloses the development of a green material that exhibits high efficacy in a sustainable transformation, highlighting key parameters that should be generally taken into account in the design of an industrially relevant chemocatalytic technology.
Valorization of bio-glycerol: New catalytic materials for the synthesis of glycerol carbonate via glycerolysis of urea
Aresta, Michele,Dibenedetto, Angela,Nocito, Francesco,Ferragina, Carla
, p. 106 - 114 (2009)
The glycerolysis of urea plays an important role in the conversion of glycerol into glycerol carbonate because it is a phosgene-free process that uses easily available and low-cost raw materials that have a low toxicity. γ-Zirconium phosphate shows a good
Hydroxy-functionalized imidazolium bromides as catalysts for the cycloaddition of CO2 and epoxides to cyclic carbonates
Anthofer, Michael H.,Wilhelm, Michael E.,Cokoja, Mirza,Drees, Markus,Herrmann, Wolfgang A.,Kühn, Fritz E.
, p. 94 - 98 (2015)
Hydroxy-functionalized mono- and bisimidazolium bromides were synthesized and applied as catalysts for the cycloaddition of CO2 and epoxides to cyclic carbonates. A catalyst screening showed the influence of the number of protic hydrogen atoms at the cation for the activation of epoxides. The most active catalyst operates at very mild reaction conditions (70 °C, 0.4 MPa CO2) and can be easily recycled ten times without loss of activity.
Synthesis of glycerol carbonate from glycerol and urea using zinc-containing solid catalysts: A homogeneous reaction
Fujita, Shin-Ichiro,Yamanishi, Yuki,Arai, Masahiko
, p. 137 - 141 (2013)
Zinc-containing solid catalysts (zinc oxide, smectite, hydrotalcite) and several inorganic zinc salts were used to produce glycerol carbonate from glycerol and urea under solvent-free conditions at 130 °C and at a reduced pressure of 3 kPa. The leaching of Zn species was observed to occur for the solid catalysts, and the carbonate yield was shown to be correlated with the amount of zinc species dissolved into the liquid phase with a single relationship in common for all the catalysts employed. The reaction was also indicated to continue in the liquid phase alone, after the solid catalysts were removed from the reaction mixtures by filtration. The results obtained reveal that the reaction takes place homogeneously in the liquid phase irrespective of the parent solid catalysts used. Possible structure of active Zn species was discussed from the results of reaction runs under different conditions and Fourier transform infrared spectroscopy measurements of the liquid phase after the reaction.
Solvent-free carbonylation of glycerol with urea using metal loaded MCM-41 catalysts
Kondawar,Potdar,Rode
, p. 16452 - 16460 (2015)
Reacting glycerol with urea is the most attractive option for the production of glycerol carbonate (GC) as it utilizes two inexpensive chemicals readily available in the chemical cycle. The overall result is the chemical fixation of carbon dioxide. A Zn/MCM-41(im) catalyst prepared by a wet impregnation method exhibited excellent activity for the reaction of glycerol and urea with 75% glycerol conversion and 98% selectivity to GC. Such excellent activity of the catalyst is explained based on the presence of both basic and acidic sites on the same catalyst which activates the glycerol and urea molecules, respectively. This journal is
Synthesis of glycerol carbonate from glycerol and dimethyl carbonate over DABCO embedded porous organic polymer as a bifunctional and robust catalyst
Wan, Yali,Lei, Yizhu,Lan, Guosong,Liu, Dingfu,Li, Guangxing,Bai, Rongxian
, p. 267 - 275 (2018)
A large surplus of glycerol from the rapidly growing biodiesel industry has led to the conversion of glycerol into higher value-added products being of great industrial importance. In this paper, a promising route for the synthesis of glycerol carbonate from glycerol and dimethyl carbonate is described using DABCO (1,4-diazabicyclo[2.2.2]octane) embedded porous organic polymer as an efficient and robust catalyst. The porous catalyst with base sites and hydrophilic units (monoquaternized DABCO) was facilely synthesized through a one-pot radical copolymerization of divinylbenzene and vinyl functionalized DABCO monomer. By simply varying the mass ratio between divinylbenzene/DABCO monomer, the surface area, pore volume and surface wettability of the catalyst can be easily adjusted. Results of activity evaluations indicated that the catalyst with high surface area and excellent amphiphilicity exhibits much higher activity than other samples due to the enhanced accessibility of catalytic sites and mass transfer efficiency. Under the optimum reaction conditions, a 0.75 mol% catalyst loading is sufficient for excellent yield of glycerol carbonate in 60 min. Moreover, the optimized catalyst also shows excellent reusability and could be reused up to 13 consecutive recycles without obvious deactivation in activity.
Preparation of nano-CaO and catalyzing tri-component coupling transesterification to produce biodiesel
Tang, Ying,Yang, Ying,Liu, Huan,Yan, Tianlan,Zhang, Zhifang
, p. 501 - 507 (2020)
Nano-CaO with different particle sizes and crystallinity was prepared by sol-gel method. A tri-component coupling transesterification of rapeseed oil/dimethyl carbonate (DMC)/methanol was used to determine the viability of prepared nano-CaO as a basic catalyst for biodiesel synthesis. Nano-CaO exhibits better catalytic performance than commercial CaO for biodiesel production under same reaction condition. At 1:1:8 molar ratio of oil to DMC to methanol, 5 wt% nano-CaO catalyst (calcined at 800 °C), and 65 °C reaction temperature, the reaction gave the best results, and the fatty acid methyl ester yield exceeded 92% at 4 h which was 2 h shorter than that of commercial CaO. The catalyst calcined under different temperature has been characterized by BET, CO2-TPD, TGA, XRD, and SEM. As the results shows that nano-CaO calcined at 800 °C exhibited the most active which should be contributed to the presence of good dispersivity, large surface area and pore volume.
A unique zinc-organic framework constructed through: In situ ligand synthesis for conversion of CO2 under mild conditions and as a luminescence sensor for Cr2O72-/CrO42-
Song, Tian-Qun,Dong, Jie,Gao, Hong-Ling,Cui, Jian-Zhong,Zhao, Bin
, p. 13862 - 13868 (2017)
A novel zinc-organic framework, {[Zn3(tza)2(μ2-OH)2(H2O)2]·H2O}n (1) (H2tza = 1H-tetrazolate-5-acetic acid), was synthesized through an in situ generated tetrazole ligand under hydrothermal conditions. In compound 1, tza2- ligands and Zn2+ are interlinked to form 2D layers, which are further pillared through μ2-OH groups to generate a 3D framework. Thermogravimetric analysis and powder X-ray diffraction confirm that 1 has high thermal stability, pH stability and solvent stability. Catalytic studies show that 1 exhibits excellent catalytic ability for the cycloaddition of CO2 with epoxides under 50 °C and 0.1 MPa. Importantly, 1 can be reused at least six times. Furthermore, luminescence investigations indicate that 1 can serve as a recyclable luminescence sensor to efficiently detect Cr2O72-/CrO42-, and the detection limit can reach 10-6 mol L-1 and 4 × 10-6 mol L-1, respectively.
Organic-inorganic hybrids of imidazole complexes of zinc (II) for catalysts in the glycerolysis of urea
Kim, Dong-Woo,Park, Dae-Won
, p. 4632 - 4638 (2014)
Bis(alkylimidazole) complexes of zinc, (Rlm)2ZnX2, were prepared by a metal insertion reaction. The synthesized (Rlm) 2ZnX2 exhibited good catalytic performance during synthesis of glycerol carbonate (GC) from glycerol and urea. (HEIm) 2ZnCI2 with a hydroxyl group exhibited the highest GC yield during glycerolysis of urea owing to incorporation of acid-base bifunctional active sites. (Elm)2ZnX2 catalysts based on different halide anions showed increased reactivity as Cl- -, which is the order of nucleophilicity The effects of reaction parameters such as temperature, reaction time, catalyst loading, and degree of vacuum on the reactivity were also investigated. Copyright
Solventless synthesis of cyclic carbonates by direct utilization of CO2 using nanocrystalline lithium promoted magnesia
Rasal, Kalidas B.,Yadav, Ganapati D.,Koskinen, Rauli,Keiski, Riitta
, p. 200 - 208 (2018)
Cyclic carbonates are industrially important chemicals. In this work, an efficient synthesis of cyclic carbonate was achieved by cyclization of epoxide with CO2 using nanocrystalline lithium promoted magnesia (Li-MgO), without using any co-catalyst or solvent. A series of Li-MgO were prepared by gel combustion method and well characterized. Li-MgO forms active F-centers (crystallographic defect) due to the difference in valence state of lithium (Li+) and magnesium (Mg2+) and acts as an active site for CO2 activation. In the synthesis of 4-(chloromethyl)-1,3-dioxolan-2-one from epichlorohydrin, 0.75% (w/w) Li-MgO was the most active catalyst for CO2 fixation into cyclic carbonate with excellent conversion (~98%) and selectivity (100%), at 130 °C and 3 MPa of CO2 pressure. The catalyst showed structural stability and was reused for three cycles without loss of activity. The current synthesis protocol is 100% atom-efficient and thus was extended to a variety of substrates. Langmuir- Hinshelwood-Hougen-Watson (LHHW) type of mechanism was proposed and kinetics studied. Both reactants are strongly adsorbed making the overall reaction zero order with an apparent activation energy of 15.14 kcal/mol.
Microwave assisted synthesis of glycerol carbonate over LDH catalyst: Activity restoration through rehydration and reconstruction
Prakruthi,Jai Prakash,Bhat
, p. 214 - 220 (2015)
Zn-Al layer double hydroxide (LDH), as synthesized, was found to be an effective base catalyst for microwave (MW) assisted conversion of glycerol to glycerol carbonate. The used catalyst deactivated after three successive usages in the reaction necessitat
Isolation and characterization of intermediate catalytic species in the Zn-catalyzed glycerolysis of urea
Park, Jong-Ho,Choi, Ji Sik,Woo, Soo Kyoung,Lee, Sang Deuk,Cheong, Minserk,Kim, Hoon Sik,Lee, Hyunjoo
, p. 35 - 40 (2012)
Homogeneous zinc-catalyzed synthesis of glycerol carbonate from the reaction of glycerol with urea was investigated. Among the zinc-based catalysts tested, ZnCl2 showed the highest catalytic activity. Spectroscopic and elemental analyses of the
Incorporation of Zn2+ ions into the secondary structure of heteropoly tungstate: Catalytic efficiency for synthesis of glycerol carbonate from glycerol and urea
Jagadeeswaraiah,Kumar, Ch. Ramesh,Prasad, P.S. Sai,Lingaiah
, p. 2969 - 2977 (2014)
Zinc exchanged heteropoly tungstate (ZnxTPA) catalysts were prepared and characterized by FT-IR, X-ray diffraction, Laser Raman spectroscopy, temperature programmed desorption of ammonia and pyridine adsorbed FT-IR spectroscopy. The activity of the catalysts was evaluated for the carbonylation of glycerol using urea as a carbonylating agent. ZnxTPA catalysts showed high activity for glycerol carbonate synthesis compared to the parent TPA. The activity of ZnxTPA catalysts depended on the number of Zn2+ ions in the secondary structure of heteropoly tungstate. Catalysts with partial exchange of Zn with the protons of TPA (Zn 1TPA) exhibited high activity towards glycerol carbonate synthesis. Exchange of protons of TPA with Zn2+ ions resulted in generation of Lewis acidic sites. The changes in surface and structural properties of Zn 1TPA catalysts with change in calcination temperature were also evaluated. The catalytic activities of ZnxTPA catalysts were explained based on the variation in their properties. Reaction conditions such as reaction temperature, catalyst weight and glycerol to urea ratio were also optimized. the Partner Organisations 2014.
Transesterification of glycerol with dimethyl carbonate over calcined Ca-Al hydrocalumite
Zheng, Liping,Xia, Shuixin,Lu, Xiuyang,Hou, Zhaoyin
, p. 1759 - 1765 (2015)
A series of Ca-Al hydrocalumite with different Ca/Al ratios (1-6) were synthesized and used in the transesterification of glycerol with dimethyl carbonate (DMC) to glycerol carbonate (GC) under mild conditions. The calcined Ca-Al hydrocalumites were active with a selectivity toward GC that reached 97% at 93% conversion of glycerol over the sample with Ca/Al = 2 at 70 °C, 3 h, and DMC/glycerol = 3. The glycerol conversion depended mainly on the proportion of strong basic sites in the calcined Ca-Al catalysts. The Ca12Al14O33 phase in the calcined catalysts was stable, but CaO was lost in recycle experiments and thus brought deactivation.
Development of a trapezoidal MgO catalyst for highly-efficient transesterification of glycerol and dimethyl carbonate
Bai, Zongquan,Zheng, Yajun,Han, Weiwei,Ji, Yue,Yan, Tianlan,Tang, Ying,Chen, Gang,Zhang, Zhiping
, p. 4090 - 4098 (2018)
A series of micro-sized MgO catalysts with various morphologies have been prepared by varying the reaction temperature and stirring time during precipitation, and were investigated for the production of glycerol carbonate from the transesterification of glycerol with dimethyl carbonate. In contrast to other morphologies of MgO (e.g., rod-like, spherical, flower-like and nest-like), trapezoidal MgO demonstrated a superior performance with a yield of glycerol carbonate of more than 99%. Various techniques including N2 physical adsorption, XRD, CO2 chemical adsorption and EDS revealed that the unique catalytic activity of trapezoidal MgO was related to its lower specific surface area, bigger crystallite size, weaker surface basicity and fewer Mg atom vacancies compared to the other morphologies of MgO. The experimental conditions (e.g., the catalyst amount, solvent, reaction temperature and molar ratio between glycerol and dimethyl carbonate) were also found to play crucial roles in determining the yield of glycerol carbonate. Furthermore, CO2-TPD profiles and FT-IR spectra indicated that the weak surface basic sites occurring at 150 °C and the CO32- stretching vibration around 1448 cm-1 were responsible for the catalytic activity of the developed trapezoidal MgO in regeneration.
Synthesis of glycerol carbonate from glycerol and dimethyl carbonate catalyzed by calcined silicates
Wang, Song,Hao, Pengfei,Li, Sanxi,Zhang, Ailing,Guan, Yinyan,Zhang, Linnan
, p. 174 - 181 (2017)
Several anhydrous silicates were prepared by calcination at 400?°C and utilized as solid base catalyst for synthesizing glycerol carbonate (GC) by transesterification of glycerol with dimethyl carbonate (DMC). Among them, calcined sodium silicate showed the best catalytic activity with glycerol conversion of 97.7%. Then, a series of sodium silicates calcined at different temperatures were characterized using TGA, Hammett indicator method, BET, XRD, FT-IR and FESEM. Effect of calcination temperature on their catalytic ability was carefully investigated, followed by a reaction optimization study. The basicity of sodium silicates calcined at different temperatures highly depended on calcination temperature; their catalytic ability was affected by their total basicity rather than by their BET surface area; and the increased amount of strong basic sites resulted in the formation of by-product which decreased the GC yield and GC selectivity. Sodium silicate calcined at 200?°C (Na2SiO3-200), which had the intermediate total basicity and relative low amount of strong basic sites, incurred the highest GC yield. The highest catalytic performance of Na2SiO3-200 was achieved under the condition that the 4:1 molar ratio of DMC to glycerol was reacted at 75?°C for 2.5?h. This catalyst could be reused five times without noticeable drop in catalytic activity.
Direct Carbonation of Glycerol with CO2 Catalyzed by Metal Oxides
Ozorio, Leonardo P.,Mota, Claudio J. A.
, p. 3260 - 3265 (2017)
Five metal oxides (ZnO, SnO2, Fe2O3, CeO2, La2O3) were produced by the sol–gel method and tested in the direct carbonation of glycerol with CO2. Initial tests with Fe2O3 showed that the best reaction condition was 180 °C, 150 bar, and 12 h. The other oxides were evaluated at these conditions and were all active to the formation of glycerol carbonate. Zinc oxide was the most active catalyst, with a yield of 8.1 % in the organic carbonate. The catalytic activity decreased upon washing and drying the ZnO catalyst between the runs. Nevertheless, the activity is maintained if the ZnO is washed and calcined at 450 °C between the runs. FTIR and TGA results indicated the formation of ZnCO3 as the main cause of catalyst deactivation, which may be decomposed upon calcination of the material. No appreciable leaching of Zn was observed, indicating a truly heterogeneous catalysis.
Halide aided synergistic ring opening mechanism of epoxides and their cycloaddition to CO2 using MCM-41-imidazolium bromide catalyst
Adam, Farook,Appaturi, Jimmy Nelson,Ng, Eng-Poh
, p. 42 - 48 (2014)
Imidazole was immobilized on MCM-41 using 3-chloropropyltriethoxysilane (CPTES) as the anchoring agent followed by alkylation with 1,2-dibromoethane at 110 C. The resulting catalyst was designated as MCM-41-Imi/Br. The catalyst was used for the synthesis of cyclic carbonates via cycloaddition of CO2 with several epoxides under solvent free condition. The use of MCM-41-Imi (without bromide ion) to catalyze the reaction led to the elucidation of the reaction mechanism involved in the synergistic catalysis. The catalyst was used in the cycloaddition of styrene oxide, epichlorohydrine, glycidol, allyl glycidyl ether and phenyl glycidyl ether. A high yield and excellent selectivity of cyclic carbonates were obtained under optimized conditions. The yields of the respective cyclic carbonates were 98.8% for styrene oxide, 97.0% for epichlorohydrin, 98.3% for glycidol, 97.5% for allyl glycidyl ether, 96.7% for phenyl glycidyl ether and 100% for 1,2-epoxyhexane.
Glycidol: an Hydroxyl-Containing Epoxide Playing the Double Role of Substrate and Catalyst for CO2Cycloaddition Reactions
Della Monica, Francesco,Buonerba, Antonio,Grassi, Alfonso,Capacchione, Carmine,Milione, Stefano
, p. 3457 - 3464 (2016)
Glycidol is converted into glycerol carbonate (GC) by coupling with CO2in the presence of tetrabutylammonium bromide (TBAB) under mild reaction conditions (T=60 °C, PCO2=1 MPa) in excellent yields (99 %) and short reaction time (t=3 h). The unusual reactivity of this substrate compared to other epoxides, such as propylene oxide, under the same reaction conditions is clearly related to the presence of a hydroxyl functionality on the oxirane ring. Density functional theory calculations (DFT) supported by1H NMR experiments reveal that the unique behavior of this substrate is a result of the formation of intermolecular hydrogen bonds into a dimeric structure, activating this molecule to nucleophilic attack, and allowing the formation of GC. Furthermore, the glycidol/TBAB catalytic system acts as an efficient organocatalyst for the cycloaddition of CO2to various oxiranes.
Efficient bio-conversion of glycerol to glycerol carbonate catalyzed by lipase extracted from Aspergillus niger
Tudorache, Madalina,Protesescu, Loredana,Coman, Simona,Parvulescu, Vasile I.
, p. 478 - 482 (2012)
A biocatalytic synthesis of glycerol carbonate (GlyC), as an added-value product of renewable glycerol, has been developed using a catalytic route in which glycerol (Gly) was reacting with dimethyl carbonate (DMC) in the presence of lipase under solvent-free conditions. The enzyme screening indicated lipase from Aspergillus niger as the most efficient biocatalyst for the GlyC synthesis. After the optimization of the reaction conditions it was established that the best results corresponded to 12% (w/w) Aspergillus niger lipase, to a glycerol:DMC molar ratio of 1:10, to an incubation time of 4 h and to an incubation temperature of 60 °C. Consequently, the glycerol conversion was around 74%, the yield in GlyC of 59.3% and the selectivity to GlyC of 80.3%. Recycling experiments demonstrated that the biocatalyst can be successfully used for several reaction cycles (at least 4 times) and confirmed its very high stability under the reaction conditions.
The value-added utilization of glycerol for the synthesis of glycerol carbonate catalyzed with a novel porous ZnO catalyst
Zhang, Pingbo,Liu, Lihua,Fan, Mingming,Dong, Yuming,Jiang, Pingping
, p. 76223 - 76230 (2016)
In the carbonylation reaction, a novel porous ZnO was prepared by a calcination method, and the raw material Zn glycerolate platelets were prepared via the glycerol approach, which could make use of a by-product of glycerol. To elucidate their composition, morphology, and properties, the resulting materials were characterized by FT-IR, XRD, SEM, BET, XPS, TPD and TG. The results showed that the catalyst was porous and irregularly shaped with appropriate acid and base properties; moreover, it displayed better catalytic performance for the synthesis of glycerol carbonate. The highest glycerol carbonate yield reached 85.97% of ZnO from zinc glycerolate under the optimal reaction conditions of 5.0 wt% of catalyst, 1:1.5 molar ratio of glycerol to urea and reacting at 140 °C for 6 h under 1 kPa. Comparing the three catalysts ZnO, zinc glycerolate and ZnO from zinc glycerolate, the maximum glycerol carbonate yield was 85.97% with the ZnO from zinc glycerolate as the catalyst under optimized operating conditions. Compared with the conventional ZnO, the as-prepared catalyst embodied in its porosity, acidity and basicity. The catalyst maintained excellent catalytic performance after 5 cycles with almost no loss of catalytic activity. This study revealed that ZnO from a zinc glycerolate catalyst is highly active, highly recyclable, remarkably stable, and environmental friendly for industrial applications. Overall, this new material overcomes the limitation of glycerol application and will have a good potential for industrial application.
A highly efficient rod-like-CeO2-supported palladium catalyst for the oxidative carbonylation of glycerol to glycerol carbonate
Wang, Ziyan,Guo, Shuo,Wang, Zhimiao,Li, Fang,Xue, Wei,Wang, Yanji
, p. 17072 - 17079 (2021)
A rod-like-CeO2-supported Pd catalyst (Pd/CeO2-r) was prepared using two-step hydrothermal impregnation and used in the oxidative carbonylation of glycerol to produce glycerol carbonate. The characterization results showed that the Pd was highly dispersed on the surface of the CeO2-r, and metallic Pd was the main species in the catalyst. The Pd/CeO2-r exhibited good catalytic performance for the oxidative carbonylation of glycerol. Under optimized reaction conditions, the glycerol conversion and glycerol carbonate selectivity were 93% and 98%, respectively, and turnover frequency was 1240 h?1. However, because of the leaching of Pd and the growth of Pd particles, the catalyst was gradually deactivated throughout reuse.
In situ synthesis of pyridinium-based ionic porous organic polymers with hydroxide anions and pyridinyl radicals for halogen-free catalytic fixation of atmospheric CO2
Liu, Ke,Xu, Zixuan,Huang, He,Zhang, Yadong,Liu, Yan,Qiu, Zhiheng,Tong, Minman,Long, Zhouyang,Chen, Guojian
supporting information, p. 136 - 141 (2022/01/22)
Pyridinium-based ionic porous organic polymers (Py-iPOPs) were constructed from newly designed acetonitrile-functionalized ionic liquids and multi-carbaldehyde monomers by base-catalyzed Knoevenagel condensation. The obtained Py-iPOPs having in situ forme
A Zn(ii)-functionalized COF as a recyclable catalyst for the sustainable synthesis of cyclic carbonates and cyclic carbamates from atmospheric CO2
Ghosh, Swarbhanu,Islam, Sk. Manirul,Sarkar, Somnath
, p. 1707 - 1722 (2022/03/02)
A simple covalent organic framework (COF) bearing β-ketoenamine units as a potential heterogeneous ligand for ZnII-catalyzed fixation and transformation of CO2 into value-added chemicals is reported. Catalytic investigations convincingly demonstrated that the ZnII-functionalized covalent organic framework (Zn@TpTta) exhibits perfect catalytic activity in the fixation of CO2 for diverse epoxides with various substituents under sustainable conditions. A variety of terminal epoxides and slightly more complicated disubstituted epoxides were transformed into the corresponding cyclic carbonates with satisfactory to excellent yields (i.e., 69 to 99% yield) upon exposure to CO2 (1 atm) under solvent-free conditions (sustainable approach). On the other hand, this ZnII-loaded covalent organic framework also displayed excellent performance in facilitating atmospheric cyclizative CO2 capture, which led to the formation of diverse cyclic carbamates (i.e., 61 to 94% yield) from unsaturated amine systems using N-iodosuccinimide (NIS) as an iodinating agent and PEG-400 as a biodegradable and green polymeric solvent under base-free conditions (sustainable approach). The newly synthesized COF-based catalyst, namely, Zn@TpTta, has been completely characterized by SEM (scanning electron microscopy), EDX (energy dispersive X-ray analysis), HRTEM (high-resolution transmission electron microscopy), BET (Brunauer-Emmett-Teller), PXRD (powder X-ray diffraction), XPS (X-ray photoelectron spectroscopy), ICP (inductively coupled plasma), etc. More intriguingly, the catalytic system could be recycled over five times without a noticeable loss of catalytic performance for both reactions. This study opens an avenue for the Zn(ii) embedded COF as a promising platform for regulating regioselectivity.
Rosin-based porous heterogeneous catalyst functionalized with hydroxyl groups and triazole groups for CO2 chemical conversion under atmospheric pressure condition
Gao, Jinbin,Lai, Shilin,Xiong, Xingquan
, (2021/07/14)
Development of efficient, green and recyclable heterogeneous catalysts for the chemical conversion of CO2 into cyclic carbonates with excellent yields under atmospheric pressure condition is still a very challenging task. Herein, a class of biomass-derived hyper-cross-linked porous heterogeneous catalysts MPAc-Br and MPAc-OH-Br, based on easily available and sustainable rosin, was synthesized by Friedel–Crafts polymerization and the further N-alkylation of triazole groups. Compared with MPAc-Br, the bifunctional catalyst MPAc-OH-Br (bearing triazole IL groups and -OH groups) exhibited higher catalytic activity for direct chemical conversion of CO2 into cyclic carbonates (up to 99% yields) under metal-, solvent-free and atmospheric pressure conditions. The rosin-based porous molecular structure and bifunctional groups on the surface of MPAc-OH-Br played a very important role in the promoting the cycloaddition of CO2 with epoxides under the optimal conditions. Furthermore, MPAc-OH-Br exhibited good stability and reusability (96% yield after 10 recycles).