540-10-3Relevant articles and documents
Esterification of cetyl alcohol with palmitic acid over WO3/Zr-SBA-15 and Zr-SBA-15 catalysts
Mutlu, Vahide Nuran,Yilmaz, Selahattin
, p. 194 - 200 (2016)
Tungsten loaded and Zr incorporated SBA-15 catalysts (WO3/Zr-SBA-15 and Zr-SBA-15) were developed for esterification of cetyl alcohol and palmitic acid. The influence of the Zr content, tungsten loading amount, calcination temperature, feed composition and catalyst amount has been studied. Higher tungsten loading decreased the acidity due to formation of WO3 crystals whereas calcination temperature enhanced the acidity by favoring the dispersion of WOx species. Activities of the catalyst changed depending on their amount of Br?nsted sites and total number of acid sites. Zr-SBA-15 catalyst which had the highest amount of Br?nsted acid sites gave maximum cetyl palmitate yield (63.1%). This catalyst retained its activity up to 3 reuse cycles without significant loss of activity.
Ni-Based heterogeneous catalysts for the transformation of fatty acids into higher yields of O-free hydrocarbons
Aburto, Jorge,Gómez-Pérez, María Teresa,Gómora-Herrera, Diana,Valencia, Diego,Zenteno, Citlalli
, p. 3470 - 3480 (2020/06/25)
A series of novel catalytic materials were synthesized by changing the chemical compounds in the impregnation solutions. A rigid, aromatic and bidentate molecule 1,10-phenanthroline (PhN) was used as a ligand to bind Ni2+species prior to impregnation into a mesoporous KIT-5 support. Thein situsynthesized coordination compounds were impregnated into KIT-5 and the resulting materials exhibited better dispersion of metal species, being the best at a molar ratio Ni?:?PhN = 1?:?1. The materials were tested in the hydrodeoxygenation (HDO) of palmitic acid. We found that highly active and stable catalysts were obtained when using PhN as a chelating agent in the impregnation solution. The selectivity of these materials is remarkable since only O-free molecules were detected in the HDO products. Therefore, Ni-PhN complexes in combination with mesoporous SiO2can be further exploited for the catalytic transformation of biomass feedstocks.
Paving the way towards green catalytic materials for green fuels: Impact of chemical species on Mo-based catalysts for hydrodeoxygenation
Valencia, Diego,Díaz-García, Leonardo,Ramírez-Verduzco, Luis Felipe,Qamar, Amir,Moewes, Alexander,Aburto, Jorge
, p. 18292 - 18301 (2019/07/03)
A series of Mo-based catalysts were synthesized by tuning the sulfidation temperature to produce mixtures of MoO3 and MoS2 as active phases for the hydrodeoxygenation (HDO) of palmitic acid. Differences in the oxidation states of Mo, and the chemical species present in the catalytic materials were determined by spectroscopic techniques. Palmitic acid was used as a fatty-acid model compound to test the performance of these catalysts. The catalytic performance was related to different chemical species formed within the materials. Sulfidation of these otherwise inactive catalysts significantly increased their performance. The catalytic activity remains optimal between the sulfidation temperatures of 100 °C and 200 °C, whereas the most active catalyst was obtained at 200 °C. The catalytic performance decreased significantly at 400 °C due to a higher proportion of sulfides formed in the materials. Furthermore, the relative proportion of MoO3 to MoS2 is essential to form highly active materials to produce O-free hydrocarbons from biomass feedstock. The transition from MoS2 to MoO3 reveals the importance of Mo-S and Mo-O catalytically active species needed for the HDO process and hence for biomass transformation. We conclude that transitioning from MoS2 to MoO3 catalysts is a step in the right direction to produce green fuels.
PRODUCTION METHOD OF ESTER COMPOUND
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Paragraph 0030; 0032; 0033; 0035-0047, (2019/10/01)
PROBLEM TO BE SOLVED: To produce an ester compound at a high conversion even under mild reaction conditions. SOLUTION: A production method of an ester compound includes a reaction step for reacting a carboxylic acid of 8-22 carbons and an alcohol of 8-22 carbons at a temperature of 50-100°C in an ionic liquid composed of a phosphonium cation or an imidazolium cation and a trifluoromethanesulfonic acid anion or a bis (trifluoromethanesulfonyl) imide anion to obtain an ester compound in a liquid phase different from an ionic liquid phase. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
Aldehyde effect and ligand discovery in Ru-catalyzed dehydrogenative cross-coupling of alcohols to esters
Jiang, Xiaolin,Zhang, Jiahui,Zhao, Dongmei,Li, Yuehui
, p. 2797 - 2800 (2019/03/27)
The presence of different aldehydes is found to have a significant influence on the catalytic performance when using PN(H)P type ligands for dehydrogenation of alcohols. Accordingly, hybrid multi-dentate ligands were discovered based on an oxygen-transfer alkylation of PNP ligands by aldehydes. The relevant Ru-PNN(PO) system provided the desired unsymmetrical esters in good yields via acceptorless dehydrogenation of alcohols. Hydrogen bonding interactions between the phosphine oxide moieties and alcohol substrates likely assisted the observed high chemoselectivity.
Oxidative esterification of primary alcohols at room temperature under aqueous medium
Reddy, N. Naresh Kumar,Ravi, Chitrakar,Adimurthy, Subbarayappa
, p. 1663 - 1670 (2018/06/15)
Oxidative esterification of aliphatic primary alcohols with bromide and bromate couple in aqueous acidic medium at room temperature is reported with a wide range of substrate scope for both aliphatic and cyclic alcohols and obtained excellent yields of products.
Effect of precursor on the catalytic properties of Ni2P/SiO2 in methyl palmitate hydrodeoxygenation
Shamanaev, Ivan V.,Deliy, Irina V.,Aleksandrov, Pavel V.,Gerasimov, Evgeny Yu.,Pakharukova, Vera P.,Kodenev, Evgeny G.,Ayupov, Artem B.,Andreev, Andrey S.,Lapina, Olga B.,Bukhtiyarova, Galina A.
, p. 30372 - 30383 (2017/02/23)
The effect of phosphorus precursor on the physicochemical and catalytic properties of silica-supported nickel phosphide catalysts in the hydrodeoxygenation (HDO) of aliphatic model compound methyl palmitate (C15H31COOCH3) has been considered. Nickel aceta
Hydrodeoxygenation (HDO) of methyl palmitate over bifunctional Rh/ZrO2 catalyst: Insights into reaction mechanism via kinetic modeling
Bie, Yuwei,Lehtonen, Juha,Kanervo, Jaana
, p. 183 - 190 (2016/09/13)
Hydrodeoxygenation (HDO) of triglycerides into hydrocarbons is a novel catalytic process for the production of green biofuels. In this work, the HDO reaction mechanism over Rh/ZrO2 catalyst was studied by selecting methyl palmitate as a model compound. HDO of methyl palmitate proceeded initially via the hydrogenolysis into palmitic acid intermediate, followed by sequential hydrogenation-decarbonylation reaction into pentadecane via aldehyde intermediate. Bifunctional mechanism of the Rh/ZrO2 catalyst is advocated for the HDO process, in which both Rh sites and oxygen vacancy sites on ZrO2 synergistically contribute to the catalysis. The interface between Rh nanoparticle and support was proposed to host the most active sites. Based on our earlier work, a surface reaction mechanism was proposed and slightly modified to develop a set of mechanistic kinetic models. The mechanistic model consisting of two distinct types of adsorption sites for oxygenated components and H2, gave a good fitting to the kinetic data over a broad range of reaction conditions and conversion levels.
Unprecedented reductive esterification of carboxylic acids under hydrogen by reusable heterogeneous platinum catalysts
Touchy, Abeda S.,Kon, Kenichi,Onodera, Wataru,Shimizu, Ken-Ichi
, p. 1499 - 1506 (2015/05/19)
Supported metal catalysts have been tested for an unprecedented reductive dimerization of carboxylic acids to esters under 8 bar hydrogen in solvent-free conditions. Among various metal-loaded tin oxide catalysts, platinum-loaded tin dioxide (Pt/SnO2) shows the highest ester yield for the reaction of dodecanoic acid. Among Pt catalysts on various supports, Lewis acidic oxides, especially SnO2, show high activity. The most active catalyst, 5 wt% Pt/SnO2 reduced at 100°C, is effective for the reductive esterification of various carboxylic acids, and the catalyst is reusable for nine cycles, demonstrating the first successful example for the title reaction. Infrared (IR) studies of a model compound (formic acid) on some metal oxides indicate a strong Lewis acid-base interaction between SnO2 and the carbonyl oxygen. For Pt/SnO2 catalysts with different Pt particle sizes, the activity increases with decreasing size of Pt metal. A cooperative catalysis of the Pt metal nanoparticles and the Sn4+ Lewis acid sites is proposed.
Manipulating catalytic pathways: Deoxygenation of palmitic acid on multifunctional catalysts
Peng, Baoxiang,Zhao, Chen,Kasakov, Stanislav,Foraita, Sebastian,Lercher, Johannes A.
, p. 4732 - 4741 (2013/05/22)
The mechanism of the catalytic reduction of palmitic acid to n-pentadecane at 260 °C in the presence of hydrogen over catalysts combining multiple functions has been explored. The reaction involves rate-determining reduction of the carboxylic group of palmitic acid to give hexadecanal, which is catalyzed either solely by Ni or synergistically by Ni and the ZrO2 support. The latter route involves adsorption of the carboxylic acid group at an oxygen vacancy of ZrO2 and abstraction of the α-H with elimination of O to produce the ketene, which is in turn hydrogenated to the aldehyde over Ni sites. The aldehyde is subsequently decarbonylated to n-pentadecane on Ni. The rate of deoxygenation of palmitic acid is higher on Ni/ZrO2 than that on Ni/SiO2 or Ni/Al2O3, but is slower than that on H-zeolite-supported Ni. As the partial pressure of H2 is decreased, the overall deoxygenation rate decreases. In the absence of H 2, ketonization catalyzed by ZrO2 is the dominant reaction. Pd/C favors direct decarboxylation (-CO2), while Pt/C and Raney Ni catalyze the direct decarbonylation pathway (-CO). The rate of deoxygenation of palmitic acid (in units of mmol moltotal metal -1 h-1) decreases in the sequence r (Pt black)≈r(Pd black)>r(Raney Ni) in the absence of H2. In situ IR spectroscopy unequivocally shows the presence of adsorbed ketene (Ci?￡34;Ci?￡34;O) on the surface of ZrO2 during the reaction with palmitic acid at 260 °C in the presence or absence of H2. Biomass to biofuels: The conversion of palmitic acid to n-pentadecane over ZrO2 mainly proceeds by hydrogenation of the carboxylic acid group to give hexadecanal (rate-determining step), which is catalyzed either solely by Ni sites or synergistically by Ni sites and sites on the ZrO2 support (see scheme). In the absence of H2, ketonization is the dominant reaction catalyzed by ZrO 2. Copyright
