Crossed Aldol Condensation Reactions between Various Aldehydes and Acetone Using Solid Base Catalysts

The vapor-phase aldol condensation of methyl acetate (MeOAC) with formaldehyde (HCHO) to form methyl acrylate was investigated over solid base catalysts. A variety of solid base catalysts were prepared by loading Cs2O over SiO2 or Al2O3 as the support materials. The properties of the solid base catalysts were characterized by XRD, BET and CO2-TPD. The results of the vapor-phase aldol condensation indicated that SiO2 and Al2O3 modified with Cs2O showed high conversation of methyl acetate and high selectivity of methyl acrylate. 22.6% conversation of methyl acetate and 16.5% yield of acrylic acid and methyl acrylate were obtained over Cs-Al2O3. In addition, Cs-SiO2 exhibited about 42% selectivity to methyl acetate. The high yield of acrylic acid and methyl acrylate is attributed to the high base property of catalysts.

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On the Structure of Activated Hydrotalcites as Solid Base Catalysts for Liquid-Phase Aldol Condensation

Journal of Catalysis ◽

10.1006/jcat.2001.3295 ◽

2001 ◽

Vol 203 (1) ◽

pp. 184-191 ◽

Cited By ~ 144

Author(s):

J.C.A.A. Roelofs ◽

D.J. Lensveld ◽

A.J. van Dillen ◽

K.P. de Jong

Keyword(s):

Liquid Phase ◽

Aldol Condensation ◽

Solid Base ◽

Solid Base Catalysts ◽

Base Catalysts

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Structured hydroxyapatite composites as efficient solid base catalysts for condensation reactions

Catalysis Science & Technology ◽

10.1039/d1cy00102g ◽

2021 ◽

Author(s):

Tharun Jose ◽

Jamal Ftouni ◽

Pieter C. A. Bruijnincx

Keyword(s):

Solid Base ◽

Solid Base Catalysts ◽

Base Catalysts ◽

Condensation Reactions ◽

Highly Efficient ◽

Hydroxyapatite Composite

Herein, we report the use of structured hydroxyapatite composite (SHCs) as highly efficient and recyclable solid base catalysts for various condensation reactions.

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Operando Spectroscopy of the Gas-Phase Aldol Condensation of Propanal over Solid Base Catalysts

Topics in Catalysis ◽

10.1007/s11244-017-0836-7 ◽

2017 ◽

Vol 60 (19-20) ◽

pp. 1522-1536 ◽

Cited By ~ 14

Author(s):

Ana M. Hernández-Giménez ◽

Javier Ruiz-Martínez ◽

Begoña Puértolas ◽

Javier Pérez-Ramírez ◽

Pieter C. A. Bruijnincx ◽

...

Keyword(s):

Gas Phase ◽

Aldol Condensation ◽

Solid Base ◽

Operando Spectroscopy ◽

Solid Base Catalysts ◽

Base Catalysts

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Waste Seashells as a Highly Active Catalyst for Cyclopentanone Self-Aldol Condensation

Catalysts ◽

10.3390/catal9080661 ◽

2019 ◽

Vol 9 (8) ◽

pp. 661 ◽

Cited By ~ 5

Author(s):

Sheng ◽

Xu ◽

Wang ◽

Li ◽

Jia ◽

...

Keyword(s):

High Performance ◽

Aldol Condensation ◽

Solid Base ◽

X Ray Diffraction ◽

Solid Base Catalysts ◽

Base Catalysts ◽

Highly Active ◽

Activity Sequence ◽

Waste Shell ◽

Temperature Programmed

For the first time, waste-seashell-derived CaO catalysts were used as high-performance solid base catalysts for cyclopentanone self-condensation, which is an important reaction in bio-jet fuel or perfume precursor synthesis. Among the investigated seashell-derived catalysts, Scapharca Broughtonii-derived CaO catalyst (S-shell-750) exhibited the highest dimer yield (92.1%), which was comparable with commercial CaO (88.2%). The activity sequence of different catalysts was consistent with the CaO purity sequence and contact angle sequence. X-ray diffraction (XRD) results showed that CaCO3 in waste shell were completely converted to CaO after calcination at 750 °C or above for 4 h. CO2 temperature-programmed desorption (CO2-TPD) results indicate that both the amount and strength of base sites increase significantly when the calcination temperature climbs to 750 °C. Therefore, we can attribute the excellent performance of S-shell-750/850/950 catalysts to the higher CaO content, relatively low hydrophilicity, and stronger acidity and basicity of this catalyst. This study developed a new route for waste shell utilization in bio-derived ketone aldol condensation.

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