629-62-9Relevant articles and documents
Palladium-catalyzed transformation of renewable oils into diesel components
Han, Junxing,Sun, Hui,Duan, Jinzhao,Ding, Yuqi,Lou, Hui,Zheng, Xiaoming
, p. 1805 - 1809 (2010)
A size-controlled palladium nanoparticle catalyst prepared by adsorption of colloidal palladium nanoparticles on barium sulfate is efficient and highly selective in transforming vegetable oils into diesel-like fuel. Preliminary kinetic investigations using model compounds indicated that decarboxylation of aliphatic esters on palladium in a hydrogenrich atmosphere showed a zero-order rate. Hydrogen temperature-programmed desorption measurements revealed that the high-temperature desorption of hydrogen species might be the rate-determining step.
New and Improved Methods for the Radical Decarboxylation of Acids
Barton, Derek H. R.,Crich, David,Motherwell, William B.
, p. 939 - 941 (1983)
Carboxylic acid esters derived from N-hydroxypyridine-2-thione undergo efficient radical chain decarboxylation to the corresponding nor-alkane on treatment with either tri-n-butylstannane or t-butylmercaptan; in the absence of these hydrogen atom donors a smooth decarboxylative rearrangement giving noralkyl 2-pyridyl sulphides is observed.
Highly stable and selective catalytic deoxygenation of renewable bio-lipids over Ni/CeO2-Al2O3 for N-alkanes
Ba, Wenxia,Cui, Huamin,Fu, Lin,Li, Yongfei,Liu, Yuejin
, (2021/07/31)
Ni-based catalysts are easy deactivated in bio-lipids deoxygenation due to metal aggregation and Ni leaching. They also suffer from the hydrocracking of C–C bonds due to strong acidity at high reaction temperature (≥ 300 ℃). Herein, a series of Ni/CeO2-Al2O3 catalysts with different Ce/Al ratio were prepared by one-pot sol-gel method. The characteristic results showed that an appropriate addition of Ce both increase the catalytic activity and stability in bio-lipids deoxygenation. The oxygen vacancies formed by Ce introduction weaken the strong interaction of Ni-Al, thus improving Ni sites dispersion. Additional, Ce-addition in NiCeAl system increases weak and medium acidity and decreases strong acidity, preventing the C–C bond cleavage of hydrocarbon. As the result, the Ni/CeAl-3.0 catalyst afforded a 97.1 % n-C17 yield at 99.9 % MO conversion under 2.5 MPa H2 at 300 ℃ for 6 h. Minor C15-16 alkanes (17 yield). After simple regeneration, n-C17 yield was recovered to 95 %. Furthermore, non-edible bio-lipids (JO and WCO) can be converted to C13-18 alkanes with 95.2 % and 93.8 % yields, respectively.
Light-Driven Enzymatic Decarboxylation of Dicarboxylic Acids
Chen, Bi-Shuang,Liu, Lan,Zeng, Yong-Yi,Zhang, Wuyuan
, p. 553 - 559 (2021/06/25)
Photodecarboxylase from Chlorella variabillis (CvFAP) is one of the three known light-activated enzymes that catalyzes the decarboxylation of fatty acids into the corresponding C1-shortened alkanes. Although the substrate scope of CvFAP has been altered by protein engineering and decoy molecules, it is still limited to mono-fatty acids. Our studies demonstrate for the first time that long chain dicarboxylic acids can be converted by CvFAP. Notably, the conversion of dicarboxylic acids to alkanes still represents a chemically very challenging reaction. Herein, the light-driven enzymatic decarboxylation of dicarboxylic acids to the corresponding (C2-shortened) alkanes using CvFAP is described. A series of dicarboxylic acids is decarboxylated into alkanes in good yields by means of this approach, even for the preparative scales. Reaction pathway studies show that mono-fatty acids are formed as the intermediate products before the final release of C2-shortened alkanes. In addition, the thermostability, storage stability, and recyclability of CvFAP for decarboxylation of dicarboxylic acids are well evaluated. These results represent an advancement over the current state-of-the-art.
Recent trends for clean fuel production by deoxygenation of pure palmitic acid using Ni/C catalyst
Rashad, Ahmed M.,El Sharkawy, Heba M.,Ebiad, Mohamed A.,El sayed, Hessin A.,Tantawy, Ahmed H.,Hebash, Kaouser A.,El sabagh, Seham M.,Taman, Afaf R.
, p. 883 - 892 (2021/02/09)
Deoxygenation of triglycerides is one of key processes making possible a convenient production of high quality automotive fuels components (sulfur-, oxygen- and aromatics-free). This reaction was studied over non noble metal catalysts 20wt%Ni/C and performed in batch reactor system (autoclave) by using pure palmitic acid, nhexane as a solvent and 200 psi pressure. The effect of different atmospheres (pure hydrogen, pure nitrogen, and mixture of 50 psi H2/150psiN2) and different temperature range (300 °C-350 °C) under a mixed atmosphere (50 psiH2/150psi N2) were studied in this paper. The main product was n-pentadecane (C15) which the catalyst Ni/C has lower cracking selectivity to light hydrocarbons. The total conversion of carboxylic groups of palmitic acid and the selectivity to C15 in case of pure nitrogen are (22.29% and 12.38%) respectively and in case of hydrogen they are (75.16% and 80.07%) respectively. In case of using H2/N2 as a mixture the total conversion and the selectivity are (81.18% and 75.32%) respectively for Ni/C catalyst. The total conversion increases from 81.18% to 99.99% by increase the temperature from 300 °C to 350 °C. The deoxygenation of palmitic acid over 20wt%Ni/C catalyst indicated that the high selectivity for n-alkane (C15) (75.32%) at 300 °C and reach maximum value (98.11%) at 350 °C. Analysis of liquid products by gas chromatography (GC) was used to determine n-alkane (C15) yield and other products (isomeres, olefins and dimers). Insights pertaining to the reaction scheme and an assessment of the reaction products as liquid transportation fuels are also provided in this contribution.