scholarly journals Immobilizing Polyether Imidazole Ionic Liquids on ZSM-5 Zeolite for the Catalytic Synthesis of Propylene Carbonate from Carbon Dioxide

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2710 ◽  
Author(s):  
Liying Guo ◽  
Xianchao Jin ◽  
Xin Wang ◽  
Longzhu Yin ◽  
Yirong Wang ◽  
...  

Traditional ionic liquids (ILs) catalysts suffer from the difficulty of product purification and can only be used in homogeneous catalytic systems. In this work, by reacting ILs with co-catalyst (ZnBr2), we successfully converted three polyether imidazole ionic liquids (PIILs), i.e., HO-[Poly-epichlorohydrin-methimidazole]Cl (HO-[PECH-MIM]Cl), HOOC-[Poly-epichlorohydrin-methimidazole]Cl (HOOC-[PECH-MIM]Cl), and H2N-[Poly-epichlorohydrin-methimidazole]Cl (H2N-[PECH-MIM]Cl), to three composite PIIL materials, which were further immobilized on ZSM-5 zeolite by chemical bonding to result in three immobilized catalysts, namely ZSM-5-HO-[PECH-MIM]Cl/[ZnBr2], ZSM-5-HOOC-[PECH-MIM]Cl/[ZnBr2], and ZSM-5-H2N-[PECH-MIM]Cl/[ZnBr2]. Their structures, thermal stabilities, and morphologies were fully characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The amount of composite PIIL immobilized on ZSM-5 was determined by elemental analysis. Catalytic performance of the immobilized catalysts was evaluated through the catalytic synthesis of propylene carbonate (PC) from CO2 and propylene oxide (PO). Influences of reaction temperature, time, and pressure on catalytic performance were investigated through the orthogonal test, and the effect of catalyst circulation was also studied. Under an optimal reaction condition (130 °C, 2.5 MPa, 0.75 h), the composite catalyst, ZSM-5-HOOC- [PECH-MIM]Cl/[ZnBr2], exhibited the best catalytic activity with a conversion rate of 98.3% and selectivity of 97.4%. Significantly, the immobilized catalyst could still maintain high heterogeneous catalytic activity even after being reused for eight cycles.

1988 ◽  
Vol 53 (8) ◽  
pp. 1636-1646 ◽  
Author(s):  
Viliam Múčka ◽  
Kamil Lang

Some physical and catalytic properties of the two-component copper(II)oxide-chromium(III)oxide catalyst with different content of both components were studied using the decomposition of the aqueous solution of hydrogen peroxide as a testing reaction. It has been found that along to both basic components, the system under study contains also the spinel structure CuCr2O4, chromate washable by water and hexavalent ions of chromium unwashable by water. The soluble chromate is catalytically active. During the first period of the reaction the equilibrium is being established in both homogeneous and heterogeneous catalytic systems. The catalytic activity as well as the specific surface area of the washed solid is a non-monotonous function of its composition. It seems highly probable that the extreme values of both these quantities are not connected with the detected admixtures in the catalytic system. The system under study is very insensitive with regard to the applied doses of gamma radiation. Its catalytic properties are changed rather significantly after the thermal treatment and particularly after the partial reduction to low degree by hydrogen. The observed changes of the catalytic activity of the system under study are very probably in connection with the changes of the valence state of the catalytically active components of the catalyst.


2021 ◽  
Vol 08 ◽  
Author(s):  
Vivek Srivastava

Background: Baylis-Hillman reaction suffers from the requirement of cheap starting materials, easy reaction protocol, possibility to create the chiral center in the reaction product has increased the synthetic efficacy of this reaction, and high catalyst loading, low reaction rate, and poor yield. Objective: The extensive use of various functional or non-functional ionic liquids (ILs) with organocatalyst increases the reaction rate of various organic transformations as a reaction medium and as a support to anchor the catalysts. Methods: In this manuscript, we have demonstrated the synthesis of quinuclidine-supported trimethylamine-based functionalized ionic liquid as a catalyst for the Baylis-Hillman reaction. Results: We obtained the Baylis-Hillman adducts in good, isolated yield, low catalyst loading, short reaction time, broad substrate scope, accessible product, and catalyst recycling. N-((E,3S,4R)-5-benzylidene-tetrahydro-4-hydroxy-6-oxo-2H-pyran-3-yl) palmitamide was also successfully synthesized using CATALYST-3 promoted Baylis-Hillman reaction. Conclusion: We successfully isolated the 25 types of Baylis-Hillman adducts using three different quinuclidine-supported ammonium-based ionic liquids such as Et3AmQ][BF4] (CATALYST-1), [Et3AmQ][PF6] (CATALYST-2), and [TMAAmEQ][NTf2](CATALYST-3) as new and efficient catalysts. Tedious and highly active N-((E,3S,4R)-5-benzylidene-tetrahydro-4-hydroxy-6-oxo-2H-pyran-3-yl) palmitamide derivative was also synthesized using CATALYST-3 followed by Baylis-Hillman reaction. Generally, all the responses demonstrated higher activity and yielded high competition with various previously reported homogenous and heterogeneous Catalytic systems. Easy catalyst and product recovery followed by six catalysts recycling were the added advantages of the prosed catalytic system.


2015 ◽  
Vol 68 (10) ◽  
pp. 1513 ◽  
Author(s):  
Miaona Feng ◽  
Guoying Zhao ◽  
Hongling Gao ◽  
Suojiang Zhang

Novel tetracarboxyl-functionalized 2,2′-biimidazolium-based ionic liquids (ILs) with different anions were synthesized in two steps from readily available and sustainable starting materials including ammonium acetate, glyoxal, and halogenated propionic acid. The functionalized IL exhibited higher catalytic activity towards the cycloaddition of CO2 to terminal epoxides. With propylene oxide as a substrate, the optimum yield of propylene carbonate reached 82.7 % at an initial CO2 pressure of 2.0 MPa for 4 h at 140°C. Moreover, the functionalized IL catalyst displayed a high stability and can be reused for at least five cycles without obvious loss of catalytic activity. The results provide a simple and economical way to synthesize multi-functionalized imidazolium-based ILs with versatile potential applications.


2019 ◽  
Vol 43 (5-6) ◽  
pp. 211-216 ◽  
Author(s):  
Ruiyang Chen ◽  
Tong Chen ◽  
Xiaojia Hu ◽  
Youkun Fan ◽  
Gongying Wang

Glycol dicarbonate is successfully synthesized via transesterification of glycol with dimethyl carbonate. A catalyst screening is performed by studying the effect of acidity and alkalinity on the catalytic performance. The results indicate that compared with acidic catalysts, high conversions and yields are obtained with basic catalysts. Ca(OH)2, with medium-strength alkalinity, exhibits excellent catalytic activity with glycol dicarbonate yields of 95%-99% when using a fractionation reaction system.


RSC Advances ◽  
2015 ◽  
Vol 5 (71) ◽  
pp. 57968-57974 ◽  
Author(s):  
Qin Wu ◽  
Weijiao Li ◽  
Min Wang ◽  
Yu Hao ◽  
Tonghua Chu ◽  
...  

The carbon chain length of ILs has effect on its catalytic activity and [C6ImBS][HSO4]shows the best catalytic performance.


2021 ◽  
Vol 50 (10) ◽  
pp. 3682-3692
Author(s):  
Xiuru Bi ◽  
Luyao Tao ◽  
Nan Yao ◽  
Mingxia Gou ◽  
Gexin Chen ◽  
...  

A H3PO4·12WO3/OMS-2 nanocomposite catalyst doped with sodium phosphowolframate was prepared with MnSO4·H2O as Mn2+ precursor and remarkably enhanced catalytic activity and selectivity in aerobic oxidative dehydrogenation of tetrahydro-β-carboline.


2020 ◽  
Vol 20 (4) ◽  
pp. 247-259
Author(s):  
A. V. Vorotyntsev ◽  
A. N. Markov ◽  
A. N. Petukhov ◽  
V. I. Pryakhina ◽  
M. E. Atlaskina ◽  
...  

Highly selective catalytic systems with porous polymer supports immobilized with ionic liquids, which contained acceptor and donor substituents as well as various anions, were developed. Their effect on activity of the catalysts in disproportionation of trichlorosilane was studied. The catalytic activity of systems based on N-methoxy-4-methylimidazole with different counterions was shown to decrease with the growth of chemical activity of the anions from iodine to fluorine.


Catalysts ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 859 ◽  
Author(s):  
Ghaffari ◽  
Gupta ◽  
Bae ◽  
Kim

In this study, we compared the performances of three iron-containing crystalline and amorphous catalysts, that is, Fe-Zeo-A, Fe-ZSM-5, and Fe-silica, respectively, for the degradation of phenol in an aqueous solution. Catalytic activity for the degradation of phenol was assessed by heterogeneous photolysis, Fenton, and photo-Fenton oxidation. All catalysts exhibited higher activity in the photo-Fenton process. In addition, the catalyst stability was evaluated by the estimation of the iron loss and structural variations after the oxidation processes. Results revealed that Fe-silica and Fe-ZSM-5 exhibit higher catalytic activity (~100% phenol removal), while only 64% of phenol removal over Fe-Zeo-A was observed. Moreover, among all catalysts, Fe-ZSM-5 exhibited higher stability with low iron leaching, attributed to the uniform distribution of bonded Fe in the crystalline framework and narrow channels. On the contrary, amorphous Fe-silica exhibited higher iron leaching due to the presence of isolated iron species in the structure, leading to the partial involvement of a homogeneous reaction during the degradation of phenol. The structural stability of Fe-based catalysts was examined using microscopic and spectroscopic techniques.


Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 772
Author(s):  
Tian Zhao ◽  
Hexin Zhu ◽  
Ming Dong

A new efficient polyoxometalate composite catalyst of hierarchical MIL-101 and phosphotungstic acid (PTA) was facilely prepared by the immersion method. The material was thoroughly characterized by powder x-ray diffraction (PXRD), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and inductively coupled plasma‒optical emission spectrometry (ICP-OES). Compared to the pristine nonhierarchical MIL-101 composite, the hierarchical composite demonstrated much higher catalytic performance in methanolysis of styrene oxide, such as catalytic activity and reusability.


2014 ◽  
Vol 1051 ◽  
pp. 178-181
Author(s):  
Li Ming Zhang ◽  
Hai Yan Hu

This thesis is focused on the catalyst of ionic liquids. Firstly, chloroaluminate ionic liquid consisting of triethylaminia hydrochloride and anhydrous A1C13 was prepared, and its catalytic performance on the alkylation of benzene with 1-bromobutane was studied experimentally. The composition of the system was analyzed using gas chromatogram. The effect of such influencing factors were investigated as the constitute of ionic liquid,the dosage of catalyst, the mole ratio of benzene to 1-bromobutane, temperature,reaction time,the regeneration approach of the used ionic liquid catalyst. The results suggested that it helps to increase the conversion of propylene and the selectivity of 1-butylbenzene by increasing the mole fraction of AlCl3 in the ionic liquid, the amount of catalyst, the mole ratio of benzene to 1-butylbenzene, reaction time and by reducing reaction temperature. At optimal conditions of 66.7% of mole fraction of AlCl3 in the ionic liquid, l0wt% of catalyst with respect to benzene, 10:1 of mole ratio of benzene to 1-bromobutane and 313 .15K, both conversion of 1-bromobutane and selectivity of butylbenzene can reach 96.6% in 20 minutes. The activity of the catalyst can be basically remained after eight times reused. For the used ionic liquid, its catalytic activity can be partially recovered via adding some extra AlCl3 notwithstanding less satisfactory. The catalyst performance of ionic liquids on the esterification of ethanol with ethanonic acid was studied.


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