Characterization and catalytic performance of basaltic dust as an efficient catalyst in the liquid‐phase esterification of acetic acid with n ‐butanol

2019 ◽  
Vol 66 (7) ◽  
pp. 725-733 ◽  
Author(s):  
Abd El‐Aziz A. Said ◽  
Mohamed Th. S. Heikal ◽  
Mohamed N. Goda
Author(s):  
Simsek Veli ◽  
Avci Pinar

Abstract A new mesoporous silica SBA-16 (called SP-16) was prepared by the direct hydrothermal method using Pluronic F127 (triblock copolymer; EO106PO70EO106) as surfactant and TEOS (tetraethyl orthosilicate) as silica source. The catalyst property of the SBA-16 was attained by loading the STA (Silicotungstic acid) active compound. The loading contents of STA were determined between 5 % and 40 % based on weight ratio of W and Si (W/Si). Catalytic activities and sustainability of SP-16 (10–20 %, W/Si) catalysts were determined by esterification (liquid phase reaction methanol and acetic acid) reactions at 343-353K, under autogenic pressure, 1/1–1/2 feed molar ratios (methanol/acetic acid) and in the presence of 0.4 g catalyst in the semi-batch reactor for 6 - 24h. Acetic acid conversion values of 10 and 20 % catalysts with 1/1 molar ratio at the end of 24h were obtained as 32–52.9 % and 47–60 %, respectively. On the other hand, when 1/2 molar ratio at 353K was used, 20 % catalyst showed 82.2 % conversion. Moreover, a second reaction experiment of 10 % catalyst was also carried out in identical conditions in the presence of catalyst recovered after the first methyl acetate reaction. The first and second reaction results of 10 % catalyst indicated that catalytic activity and sustainability were preserved for both 6 and 24h analyses. The physical properties of the materials obtained were investigated by Nitrogen sorption at 77K (BET), X-ray diffraction (XRD), Fourier transform infrared spectroscopy(FT-IR), Multiple Internal Reflection (DRIFT), Thermo-gravimetry/Differential thermal analysis(TG/DTA), Scanning electron microscope (SEM) and MAPPING analysis methods.


Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 283
Author(s):  
Oxana Kholdeeva ◽  
Nataliya Maksimchuk

In recent years, metal–organic frameworks (MOFs) have received increasing attention as selective oxidation catalysts and supports for their construction. In this short review paper, we survey recent findings concerning use of MOFs in heterogeneous liquid-phase selective oxidation catalysis with the green oxidant–aqueous hydrogen peroxide. MOFs having outstanding thermal and chemical stability, such as Cr(III)-based MIL-101, Ti(IV)-based MIL-125, Zr(IV)-based UiO-66(67), Zn(II)-based ZIF-8, and some others, will be in the main focus of this work. The effects of the metal nature and MOF structure on catalytic activity and oxidation selectivity are analyzed and the mechanisms of hydrogen peroxide activation are discussed. In some cases, we also make an attempt to analyze relationships between liquid-phase adsorption properties of MOFs and peculiarities of their catalytic performance. Attempts of using MOFs as supports for construction of single-site catalysts through their modification with heterometals will be also addressed in relation to the use of such catalysts for activation of H2O2. Special attention is given to the critical issues of catalyst stability and reusability. The scope and limitations of MOF catalysts in H2O2-based selective oxidation are discussed.


2000 ◽  
Vol 30 (11) ◽  
pp. 1887-1893 ◽  
Author(s):  
N. Narender ◽  
P. Srinivasu ◽  
S. J. Kulkarni ◽  
K. V. Raghavan
Keyword(s):  

ChemInform ◽  
2010 ◽  
Vol 31 (34) ◽  
pp. no-no
Author(s):  
N. Narender ◽  
P. Srinivasu ◽  
S. J. Kulkarni ◽  
K. V. Raghavan
Keyword(s):  

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1890
Author(s):  
Xiang Lai ◽  
Xuan Zhang ◽  
Shukai Li ◽  
Jie Zhang ◽  
Weifeng Lin ◽  
...  

Water soluble organic molecular pollution endangers human life and health. It becomes necessary to develop highly stable noble metal nanoparticles without aggregation in solution to improve their catalytic performance in treating pollution. Polyethyleneimine (PEI)-based stable micelles have the potential to stabilize noble metal nanoparticles due to the positive charge of PEI. In this study, we synthesized the amphiphilic PEI-oleic acid molecule by acylation reaction. Amphiphilic PEI-oleic acid assembled into stable PEI-oleic acid micelles with a hydrodynamic diameter of about 196 nm and a zeta potential of about 34 mV. The PEI-oleic acid micelles-stabilized palladium nanoparticles (PO-PdNPsn) were prepared by the reduction of sodium tetrachloropalladate using NaBH4 and the palladium nanoparticles (PdNPs) were anchored in the hydrophilic layer of the micelles. The prepared PO-PdNPsn had a small size for PdNPs and good stability in solution. Noteworthily, PO-PdNPs150 had the highest catalytic activity in reducing 4-nitrophenol (4-NP) (Knor = 18.53 s−1mM−1) and oxidizing morin (Knor = 143.57 s−1M−1) in aqueous solution than other previous catalysts. The enhanced property was attributed to the improving the stability of PdNPs by PEI-oleic acid micelles. The method described in this report has great potential to prepare many kinds of stable noble metal nanoparticles for treating aqueous pollution.


Catalysts ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 370
Author(s):  
Juan Jimenez ◽  
Kathleen Mingle ◽  
Teeraya Bureerug ◽  
Cun Wen ◽  
Jochen Lauterbach

The catalytic performance of Mo8V2Nb1-based mixed-oxide catalysts for ethane partial oxidation is highly sensitive to the doping of elements with redox and acid functionality. Specifically, control over product distributions to ethylene and acetic acid can be afforded via the specific pairing of redox elements (Pd, Ni, Ti) and acid elements (K, Cs, Te) and the levels at which these elements are doped. The redox element, acid element, redox/acid ratio, and dopant/host ratio were investigated using a three-level, four-factor factorial screening design to establish relationships between catalyst composition, structure, and product distribution for ethane partial oxidation. Results show that the balance between redox and acid functionality and overall dopant level is important for maximizing the formation of each product while maintaining the structural integrity of the host metal oxide. Overall, ethylene yield was maximized for a Mo8V2Nb1Ni0.0025Te0.5 composition, while acetic acid yield was maximized for a Mo8V2Nb1Ti0.005Te1 catalyst.


2018 ◽  
Vol 42 (8) ◽  
pp. 419-423
Author(s):  
Li-Jie Zhang ◽  
Xian Yao ◽  
Ying-xin Sun ◽  
Jia-wei Zhang ◽  
Chun Cai

Pd–Ni bimetallic nanoparticles (BMNPs) supported on ZrO2 were prepared by an impregnation–reduction method. The BMNPs showed excellent catalytic performance in Suzuki carbon–carbon cross-coupling reactions and almost quantitative conversion of the substrates was obtained under mild conditions in the absence of ligand. The excellent catalytic performance of the bimetallic catalyst could be a result of the synergistic effect between the two metal components. The catalyst showed outstanding recyclability during the reaction process; no obvious decrease in catalytic performance was observed after five cycles.


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