Thermal and Catalytic Pyrolysis of Dodecanoic Acid on SAPO-5 and Al-MCM-41 Catalysts

Abstract

In this study, dodecanoic acid was decomposed during fast pyrolysis experiments either thermally or in the presence of SAPO-5 and Al-MCM-41catalysts. The catalysts were synthesized by a hydrothermal route and subsequently characterized by XRD, TPD-NH3, and TGA, and dodecanoic acid was characterized by TGA and DSC. Analysis of the post-pyrolysis products was performed online by gas chromatography coupled with mass spectrometry (GC-MS). The results from pyrolysis at 650 °C indicated that the nature of the catalysts strongly influences the composition of the products. Linear alkenes were standard products for all pyrolysis experiments, but with Al-MCM-41, various alkene isomers with a linear and cyclic structure formed, as well as saturated and aromatic hydrocarbons. As a whole, Al-MCM-41 led to a much higher dodecanoic acid conversion and higher deoxygenation than SAPO-5. As these catalysts present small differences in strong acid site density, the difference in the global conversion of dodecanoic acid could be attributed to textural characteristics such as pore volume and surface area. In this case, the textural properties of the SAPO-5 are much lower when compared to Al-MCM-41 and, due to a lower accessibility of the reactant molecule to the acidic sites of SAPO-5, partially blocked for fatty acid molecules by the considerable amount of amorphous material, as detected by XRD.

Fast Catalytic Pyrolysis of Dilaurin in the Presence of Sodium Carbonate Alone or Combined with Alumina

“…Similar to a preceding study [29], pyrolysis reactions were done using a Frontier Laboratories LTD Multi-Shot Pyrolyzer (Koriyama, Fukushima, JAPAN) Model EGA / PY-3030D connected online to a gas chromatograph coupled to a mass spectrometer Agilent GC-MS 5799A (New Castle, DE, USA). A Frontier Laboratories UA5-30M-0.25F GC column was used (30 m length, 0.25 mm diameter, 5% diphenyl stationary phase and 95% dimethylpolysiloxane, 0.25 µm film thickness), subjected to an initial temperature of 40 • C for 2 min, followed by a heating ramp at a rate of 20 • C/min up to 320 • C, with the temperature maintained for 10 more minutes.…”

Dehydrocyclization–cracking of methyl oleate by Pt catalysts supported on a ZnZSM-5–Al2O3 hierarchical composite

“…generate less aromatics in the catalytic cracking of fat-related compounds. 16 In other reports for the conversion of fats and fat-related compounds, the addition of transition metals, [17][18][19][20] the architecture of hierarchical structures, 21 the modication of the SiO 2 /Al 2 O 3 ratio, 15,22 the utilization of different catalyst systems, [23][24][25][26] etc. have been used to promote the production of aromatic compounds.…”

Catalysis for Global Development. Contributions around the Iberoamerican Federation of Catalysis

“…Catalysis plays a crucial role in environmental protection, whether by recycling waste or by reducing gas emissions that contribute to increasing global warming-thereby opening new routes for eco-friendly processes and products that are sustainable and ecologically correct. It is on these topics and directly-related subjects that sixteen selected contributions from the Iberoamerican Federation of Catalysis are gathered in this Special Issue [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16].…”