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Importance of size and distribution of Ni nanoparticles for the hydrodeoxygenation of microalgae oil
Improved synthetic approaches for preparing small-sized Ni nanoparticles (d=3 nm) supported on HBEA zeolite have been explored and compared with the traditional impregnation method. The formation of surface nickel silicate/aluminate involved in the two pr
Song, Wenji,Zhao, Chen,Lercher, Johannes A.
p. 9833 - 9842
(2013)
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Tris(trimethylsilyl)silane. A New Reducing Agent
Tris(trimethylsilyl)silane is an effective reducing agent for organic halides that functions by a free radical mechanism.It rivals tributyltin hydride in its efficiency and is a superior reagent from ecological and practical perspectives.
Chatgilialoglu, C.,Griller, D.,Lesage, M.
p. 3641 - 3642
(1988)
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One-pot synthesized hierarchical zeolite supported metal nanoparticles for highly efficient biomass conversion
Hierarchically porous zeolite supported metal nanoparticles are successfully prepared through a base-assisted chemoselective interaction between the silicon species on the zeolite crystal surface and metal salts, in which in situ construction of mesopores and high dispersion of metal species are realized simultaneously.
Wang, Darui,Ma, Bing,Wang, Bo,Zhao, Chen,Wu, Peng
p. 15102 - 15105
(2015)
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Catalytic decarboxylation of non-edible oils over three-dimensional, mesoporous silica-supported Pd
Deoxygenation of fatty acids (oleic and stearic acids) and non-edible oil (jatropha oil) over Pd(1-5 wt%) supported on two structurally different, three-dimensional, mesoporous silica (SBA-12 and SBA-16) catalysts was investigated. Pd/SBA-16 (cubic mesoporous structure with space group Im3ˉm) showed higher catalytic activity than Pd/SBA-12 (hexagonal mesoporous structure with space group p63/mmc). The influence of reaction parameters like temperature, H2 pressure and Pd content as well as the nature of the feedstock on catalytic activity and product selectivity was studied. A temperature of above 320 °C, reaction time of 5 h and Pd content (on silica surface) of 3 wt% enabled complete conversion of the fatty compounds into diesel-range hydrocarbons. Deoxygenation proceeded through hydrodeoxygenation and decarboxylation mechanisms when a saturated (stearic) acid was used as a feed while it advanced mainly through decarboxylation route when an unsaturated (oleic) acid was employed. Higher surface hydrophobicity and smaller size particles of Pd are the possible causes for the superior catalytic activity of Pd/SBA-16.
Raut, Ravindra,Banakar, Vikram V.,Darbha, Srinivas
p. 126 - 134
(2016)
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Nanocomposite Hydrogel of Pd@ZIF-8 and Laponite: Size-Selective Hydrogenation Catalyst under Mild Conditions
The composite hydrogel of a nanoscale metal–organic framework (NMOF) and nanoclay has emerged as a new soft-material with advanced properties and applications. Herein, we report a facile synthesis of a hydrogel nanocomposite by charge-assisted self-assembly of Pd@ZIF-8 nanoparticles with Laponite nanoclay which coat the surface of Pd@ZIF-8 nanoparticles. Such surface coating significantly enhanced the thermal stability of the ZIF-8 compared to the pristine framework. Further, the Pd@ZIF-8+LP hydrogel nanocomposite shows better size-selective catalytic hydrogenation of olefins than Pd@ZIF-8 nanoparticles based on selective diffusion of the substrate.
Sutar, Papri,Bakuru, Vasudeva Rao,Yadav, Pooja,Laha, Subhajit,Kalidindi, Suresh Babu,Maji, Tapas Kumar
supporting information
p. 3268 - 3272
(2021/01/21)

Acidic metal-organic framework empowered precise hydrodeoxygenation of bio-based furan compounds and cyclic ethers for sustainable fuels
Target synthesis of hydrocarbons from abundant biomass is highly desired for sustainable aviation fuels (SAFs) to meet the need for both net zero carbon emission and air pollution control. However, precise hydrodeoxygenation (PHDO) of bio-based furan compounds and cyclic ethers to isomerically pure alkanes remains a challenge in heterogenous catalysis, which usually requires delicate control of the distribution of acid and metal catalytic sites in nanoconfined space. Here we show that a nanoporous acidic metal-organic framework (MOF), namely MIL-101-SO3H, enables one-pot PHDO reactions from furan-derivative oxygenates to solely single-component alkanes by just mechanical mixing with commercial Pd/C towards highly efficient and highly selective hydrocarbon production. The superior performance of such tandem catalysts can be attributed to the preferential adsorption of oxygenate precursors and expulsion of deoxygenated intermediates benefiting from Lewis acid sites embedded in the MOF. The strong Br?nsted acidity of MIL-101-SO3H is contributed by both the -SO3H groups and the adsorbed H2O, which makes it a water-tolerant solid acid for durable PHDO processes. The simplicity of mechanical mixing of different heterogenous catalysts allows the modulation of the tandem catalysis system for optimization of the ultimate catalytic performance. This journal is
Gao, Xiang-Yu,He, Hai-Long,Li, Zhi,Liu, Dong-Huang,Wang, Jun-Jie,Xiao, Yao,Yi, Xianfeng,Zeng, Tengwu,Zhang, Yue-Biao,Zheng, Anmin,Zhou, Si-Yu
p. 9974 - 9981
(2021/12/27)

Light-Driven Enzymatic Decarboxylation of Dicarboxylic Acids
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.
Chen, Bi-Shuang,Liu, Lan,Zeng, Yong-Yi,Zhang, Wuyuan
p. 553 - 559
(2021/06/25)

Method for decarboxylation and in-situ methylation of alkyl active carboxylic ester
The invention relates to a method for decarboxylation and in-situ methylation of alkyl active carboxylic ester. The method comprises the following step: in the presence of a cobalt catalyst, a phosphine ligand and an organic solvent, reacting alkyl active carboxylic ester with a trimethyl aluminum reagent to obtain a target methylated product. According to the provided method, trimethyl aluminum is used as a methylation reagent, so that a series of important secondary carbon and tertiary carbon centers are commercially and conveniently constructed successfully; the used carboxylate substrate is rich in source and simple to synthesize; compared with a traditional synthesis method reported before, the method avoids the use of a noble metal catalyst, and meets the requirements of green environment-friendly chemistry; the functional group compatibility is wide, the method is successfully applied to gram-scale reaction, the conversion rate is high, and the method has an important syntheticchemical value.
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Paragraph 0047-0054; 0166-0172; 0203

(2020/06/20)

An unconventional DCOx favored Co/N-C catalyst for efficient conversion of fatty acids and esters to liquid alkanes
Cobalt (Co) catalysis has recently attracted significant attention in the field of biomass conversion. However, the fabrication of highly dispersive Co nanoparticles at high metal loading with selective facet exposure to achieve specific selectivity is still questionable. In this work, a nitrogen-doped carbon-supported Co catalyst is fabricated for efficient conversion of fatty acids and esters to liquid alkanes. Nitrogen-doping facilitates a highly uniform dispersion of Co nanoparticles even at a high Co loading of 10 wt% and after recycling for 5 runs. The Co/N-C catalyst affords an unconventional decarbonylation/decarboxylation (DCOx) dominant selectivity probably due to partial reduction of cobalt oxides to α-Co0 with only exposure of the (111) facet. Co-existence of Co and N-C leads to strong Lewis acidity and basicity, facilitating the interaction between catalyst and –COOH group, and some important acid-catalyzed step-reactions. The versatility of the Co/N-C catalyst is demonstrated through conversion of various fatty acids and esters.
Li, Jiang,Liu, Jiaxing,Zhang, Junjie,Wan, Tong,Huang, Lei,Wang, Xintian,Pan, Runze,An, Zhidong,Vlachos, Dionisios G.
(2019/12/26)

Cobalt-Catalyzed Decarboxylative Methylation and Ethylation of Aliphatic N-(Acyloxy)phthalimides with Organoaluminum Reagents
A cobalt-catalyzed decarboxylative methylation of aliphatic redox-active esters [ N-(acyloxy)phthalimides; RAEs] with trimethylaluminum under mild conditions was developed, providing a method for transforming a carboxylate group into a methyl group without redox fluctuation. Primary and secondary RAEs were both amenable substrates, whereas a tertiary RAE delivered an elimination product. Triethylaluminum was also used to deliver a decarboxylative ethylation product.
Wang, Ze-Zhong,Wang, Guang-Zu,Zhao, Bin,Shang, Rui,Fu, Yao
supporting information
p. 1221 - 1225
(2020/08/17)

An efficient hydrogenation catalytic model hosted in a stable hyper-crosslinked porous-organic-polymer: From fatty acid to bio-based alkane diesel synthesis
In this study, a Pd-based catalytic model over a nitrogen enriched fibrous Porous-Organic-Polymer (POP) is established to execute hydrodeoxygenation of various vegetable oils in producing potential large-scale renewable diesel. Here we report a cost-effective synthesis strategy for a new microporous hypercrosslinked POP through the FeCl3 assisted Friedel-Crafts alkylation reaction, followed by fabrication of Pd0-NPs (2-3 nm) using a solid gas phase hydrogenation route to deliver a novel catalytic system. This catalyst (called Pd@PPN) exhibits versatile catalytic performance for different types of vegetable oils including palm oil, soybean oil, sunflower oil and rapeseed oil to furnish long chain diesel range alkanes. The catalyst is comprehensively characterized using various spectroscopic tools and it shows high stability during five runs of recycling without leaching of Pd. Our results further reveal that a direct decarbonylation (DCN) pathway of fatty acids to produce alkanes with one fewer carbon is the dominant mechanism. Under optimized conditions, using stearic acid to represent the long linear carboxylic acids in the vegetable oils, up to 90% conversion with 83% selectivity of C17-alkane has been achieved on our fabricated catalyst. Density functional theory (DFT) calculations are performed to provide insights into the electronic properties of the catalyst, the mechanistic reaction pathway, the crucial role of the catalyst surface and the product selectivity trend. The strong interaction between the corrugated polymer-frame-structure and the Pd-NPs suggests the presence of high density step sites on the fabricated Pd-NP anchored within the cage of the polymer structure. DFT calculations also reveal the strong promotional effect of step sites and charge transfer in facilitating rate-limiting steps during the decarbonylation (DCN) pathway and removal of strongly bound intermediates formed during the process, therefore explaining the high activity of the fabricated Pd@PPN catayst for the hydrodeoxygenation (HDO) conversion to produce bio-based alkane diesel.
Sarkar, Chitra,Shit, Subhash Chandra,Dao, Duy Quang,Lee, Jihyeon,Tran, Ngoc Han,Singuru, Ramana,An, Kwangjin,Nguyen, Dang Nam,Le, Quyet Van,Amaniampong, Prince Nana,Drif, Asmaa,Jerome, Francois,Huyen, Pham Thanh,Phan, Thi To Nga,Vo, Dai-Viet N.,Thanh Binh, Nguyen,Trinh, Quang Thang,Sherburne, Matthew P.,Mondal, John
supporting information
p. 2049 - 2068
(2020/04/09)

Rethinking Basic Concepts-Hydrogenation of Alkenes Catalyzed by Bench-Stable Alkyl Mn(I) Complexes
An efficient additive-free manganese-catalyzed hydrogenation of alkenes to alkanes with molecular hydrogen is described. This reaction is atom economic, implementing an inexpensive, earth-abundant nonprecious metal catalyst. The most efficient precatalyst is the bench-stable alkyl bisphosphine Mn(I) complex fac-[Mn(dippe)(CO)3(CH2CH2CH3)]. The catalytic process is initiated by migratory insertion of a CO ligand into the Mn-alkyl bond to yield an acyl intermediate which undergoes rapid hydrogenolysis to form the active 16e Mn(I) hydride catalyst [Mn(dippe)(CO)2(H)]. A range of mono- A nd disubstituted alkenes were efficiently converted into alkanes in good to excellent yields. The hydrogenation of 1-alkenes and 1,1-disubstituted alkenes proceeds at 25 °C, while 1,2-disubstituted alkenes require a reaction temperature of 60 °C. In all cases, a catalyst loading of 2 mol % and a hydrogen pressure of 50 bar were applied. A mechanism based on DFT calculations is presented, which is supported by preliminary experimental studies.
Weber, Stefan,St?ger, Berthold,Veiros, Luis F.,Kirchner, Karl
p. 9715 - 9720
(2019/10/14)

Iron-catalysed allylation-hydrogenation sequences as masked alkyl-alkyl cross-couplings
An iron-catalysed allylation of organomagnesium reagents (alkyl, aryl) with simple allyl acetates proceeds under mild conditions (Fe(OAc)2 or Fe(acac)2, Et2O, r.t.) to furnish various alkene and styrene derivatives. Mechanistic studies indicate the operation of a homotopic catalyst. The sequential combination of such iron-catalysed allylation with an iron-catalysed hydrogenation results in overall C(sp3)-C(sp3)-bond formation that constitutes an attractive alternative to challenging direct cross-coupling protocols with alkyl halides.
Bernauer, Josef,Wu, Guojiao,Von Wangelin, Axel
p. 31217 - 31223
(2019/10/19)

Chemoselective Hydrodeoxygenation of Carboxylic Acids to Hydrocarbons over Nitrogen-Doped Carbon-Alumina Hybrid Supported Iron Catalysts
The establishment of catalyst systems for the chemoselective hydrodeoxygenation (HDO) of carboxylic acids to hydrocarbons, such as the HDO of long-chain fatty acids to alkanes, is important for biomass to biofuel conversion. As the most abundant and probably the cheapest transition metal on the earth, iron is a promising non-noble-metal alternative to precious metals for large-scale conversion of biomass. However, it usually suffers from unsatisfactory activity. In this work, a nitrogen-doped carbon-alumina hybrid supported iron (Fe-N-C@Al2O3) catalyst is established for chemoselective HDO of carboxylic acids to hydrocarbons. By using stearic acid HDO as the model reaction, n-octadecane and n-heptadecane are produced with yields of 91.9% and 6.0%, respectively. Triglycerides can also be converted into liquid alkanes with a total molar yield of >92%. In addition, the iron catalyst can chemoselectively catalyze the HDO of the carboxylic acid group in the presence of other functional groups such as an aromatic ring. This chemoselectivity has rarely been seen before because the aromatic ring is usually more easily hydrogenated in comparison to HDO of the carboxylic acid group. The characterization results showed that both the formation of a nitrogen-doped carbon-alumina hybrid and the iron loading are important for the Lewis basicity of these catalysts, in order to adsorb the acid substrates. The addition of melamine as the nitrogen precursor during pyrolysis eliminates undesired reactions between the iron precursor and alumina support to form an inactive hercynite phase, leading to the formation of an Fe3C active phase for the hydrogenation of -COOH to -CH2OH and the hybrid of N-C and alumina for the HDO of -CH2OH to -CH3.
Li, Jiang,Zhang, Junjie,Wang, Shuai,Xu, Guangyue,Wang, Hao,Vlachos, Dionisios G.
p. 1564 - 1577
(2019/02/03)

Catalytic deoxygenation of C18 fatty acid over supported metal Ni catalysts promoted by the basic sites of ZnAl2O4 spinel phase
Highly active Zn-Al composite oxides were synthesized via a hydrothermal process followed by thermal treatment and were used as supports to prepare Ni-based hydrogenation catalysts for catalytic deoxygenation of oleic acid, stearic acid, and 1-octadecanol. The results showed that increasing the temperature of hydrothermal synthesis changed the morphology of the Zn-Al composite oxides from sheet-like structures to spheroidal structures. High hydrothermal synthesis temperatures enhanced the interaction between Zn and Al atoms, resulting in more ZnAl2O4 spinel phase. This phase not only improved the chemical stability of the support but also supplied strong basic sites which efficiently inhibited the formation of by-products and increased the yield of heptadecane in the catalytic deoxygenation of oleic acid. Stearic acid and 1-octadecanol could be readily transformed to alkanes in the presence of metallic Ni and ZnAl2O4 phase. Decarbonylation of the octadecanal intermediate and dehydrogenation of 1-octadecanol were key reaction pathways to produce heptadecane, in which decarbonylation was catalyzed by metallic Ni, while the dehydrogenation was attributed to synergistic catalysis between metallic Ni and the strong basic sites of the support. Individual metallic Ni only catalyzed the cleavage of C-H bonds but did not affect the O-H bond of 1-octadecanol.
Li, Guangci,Chen, Lei,Fan, Ruikun,Liu, Di,Chen, Song,Li, Xuebing,Chung, Keng H.
p. 213 - 222
(2019/01/14)

Hydrodeoxygenation of Palmitic and Stearic Acids on Phosphide Catalysts Obtained In Situ in Reaction Medium
Abstract: Unsupported phosphide catalysts of composition Ni2P and CoP are prepared in situ in the reaction medium from oil-soluble precursors in the course of hydrodeoxygenation of palmitic and stearic acids. The obtained catalysts are characterized by X-ray powder diffraction and X-ray photoelectron spectroscopy; they show high activity in the hydrodeoxygenation of model substrates. After 6 h of the hydrodeoxygenation reactions, the conversion of palmitic acid reaches 93 and 92% and the conversion of stearic acid is as high as 94 and 91% in the presence of nickel phosphide and cobalt phosphide, respectively. It is shown that the catalyst formed in situ can be isolated and recycled.
Golubeva,Maksimov
p. 1326 - 1330
(2019/12/30)

Selective Hydrodeoxygenation of Vegetable Oils and Waste Cooking Oils to Green Diesel Using a Silica-Supported Ir–ReOx Bimetallic Catalyst
High yields of diesel-range alkanes are prepared by hydrodeoxygenation of vegetable oils and waste cooking oils over ReOx-modified Ir/SiO2 catalysts under mild reaction conditions. The catalyst containing a Re/Ir molar ratio of 3 exhibits the best performance, achieving 79–85 wt % yield of diesel-range alkanes at 453 K and 2 MPa H2. The yield is nearly quantitative for the theoretical possible long-chain alkanes on the basis of weight of the converted oils. The catalyst retains comparable activity upon regeneration through calcination. Control experiments using probe molecules as model substrates suggest that C=C bonds of unsaturated triglycerides and free fatty acids are first hydrogenated to their corresponding saturated intermediates, which are then converted to aldehyde intermediates through hydrogenolysis of acyl C?O bonds and subsequently hydrogenated to fatty alcohols. Finally, long-chain alkanes without any carbon loss are formed by direct hydrogenolysis of the fatty alcohols. Small amounts of alkanes with one carbon fewer are also formed by decarbonylation of the aldehyde intermediates. A synergy between Ir and partially reduced ReOx sites is discussed to elucidate the high activity of Ir–ReOx/SiO2.
Liu, Sibao,Simonetti, Trent,Zheng, Weiqing,Saha, Basudeb
p. 1446 - 1454
(2018/04/30)

Selective Hydrogenation of Carboxylic Acids to Alcohols or Alkanes Employing a Heterogeneous Catalyst
The chemoselective hydrogenation of carboxylic acids to either alcohols or alkanes is reported, employing a heterogeneous bimetallic catalyst consisting of rhenium and palladium supported on graphite. α-Chiral carboxylic acids were hydrogenated without loss of optical purity. The catalyst displays a reverse order of reactivity upon hydrogenation of different carboxylic functions with esters being less reactive than amides and carboxylic acids. This allows for chemoselective hydrogenation of an acid in the presence of an ester or an amide function.
Ullrich, Johannes,Breit, Bernhard
p. 785 - 789
(2018/02/14)

Construction of bifunctional co/h-zsm-5 catalysts for the hydrodeoxygenation of stearic acid to diesel-range alkanes
Bifunctional Co/H-ZSM-5 zeolites were prepared by a surface organometallic chemistry grafting route, namely, by the stoichiometric reaction between cobaltocene and the Br?nsted acid sites in zeolites. The catalyst was applied to a model reaction of the catalytic hydrodeoxygenation of stearic acid (SA). The cobalt species existed in the form of isolated Co2 + ions at the exchange positions after grafting, transformed to CoO species on the surface of the zeolite, stabilized inside the zeolite channels upon calcination in air, and finally reduced by hydrogen to homogeneous clusters of metallic cobalt species approximately 1.5 nm in size. During this process, the Br?nsted acid sites of the H-ZSM-5 zeolites were preserved with a slight-ly reduced acid strength. The as-prepared bifunctional catalyst exhibited an approximately 16 times higher activity for the hydrodeoxygenation of SA (2.11 gSA gcat1 h1) than the reference catalyst (0.13 gSA gcat1 h1) prepared by solid-state ion exchange and a high C18 /C17 ratio of approximately 24. The remarkable hydrodeoxygenation performance of the bifunctional Co/H-ZSM-5 was owed to the effective synergy between the uniformed metallic cobalt clusters and the Br?nsted acid sites in H-ZSM-5. The simplified reaction network and kinetics of the SA hydrodeoxygenation catalyzed by the as-prepared bifunctional Co/H-ZSM-5 zeolites were also investigated.
Wu, Guangjun,Zhang, Nan,Dai, Weili,Guan, Naijia,Li, Landong
p. , 2179
(2018/10/20)

Synthesis of mesoporous iridium nanosponge: A highly active, thermally stable and efficient olefin hydrogenation catalyst
Three dimensional porous structures offer high specific surface areas and large pore volumes, which enhance substrate diffusion within the porous structures and provide a large number of surface active sites. Such types of structures find applications in catalysis. Herein, we report a simple synthetic strategy for the preparation of iridium nanosponges by the capping agent dissolution method. An Ir@BNHx nanocomposite was prepared starting from different iridium precursors by a solid state reduction method using ammonia borane wherein iridium(0) nanoparticles are embedded in a BNHx polymer. Capping agent (here, the BNHx polymer) dissolution using water under ambient conditions resulted in the formation of a mesoporous iridium nanosponge. This iridium nanosponge exhibits a surface area of 33.5 m2 g-1. The iridium nanosponge was found to be catalytically active for hydrogenation of a variety of olefinic substrates including linear and cyclic alkenes and α,β-unsaturated esters under relatively mild conditions and exhibits high turnover frequencies. It was also found to exhibit much better catalytic activity as compared to other iridium based heterogeneous catalysts for olefin hydrogenation reactions. Additionally, catalyst recovery was achieved via simple filtration from the hydrogenation reaction mixture. The catalytically active surface area of iridium nanosponge was estimated using H2-temperature programmed desorption (TPD) experiments. Moreover, the catalyst was found to be thermally quite robust. The catalyst was recyclable over seven cycles of styrene hydrogenation and was found to be capable of hydrogenating 99% of styrene to ethyl benzene after seven cycles.
Ghosh, Sourav,Jagirdar, Balaji R.
p. 11431 - 11439
(2017/09/07)

Hydrodeoxygenation of Fatty Acids, Triglycerides, and Ketones to Liquid Alkanes by a Pt–MoOx/TiO2 Catalyst
Various supported metal catalysts are screened for hydrogenation of lauric acid and 2-octanone as model reactions for the transformation of biomass-derived oxygenates to liquid alkanes (biofuels) in a batch reactor under solvent-free conditions. Among the catalysts tested, Pt and MoOx co-loaded on TiO2 (Pt–MoOx/TiO2) shows the highest yields of n-alkanes for both of the reactions. Pt–MoOx/TiO2 selectively catalyzes the hydrodeoxygenation of various fatty acids and triglycerides to n-alkanes without C?C bond cleavage under 50 bar H2 and shows higher turnover numbers than the catalysts in the literature. Pt–MoOx/TiO2 is effective also for the hydrodeoxygenation of various ketones to the corresponding alkanes. In situ IR study of the reaction of adsorbed acetone under H2 suggests that the high activity of Pt–MoOx/TiO2 is attributed to the cooperation between Pt and Lewis acid sites of the MoOx/TiO2 support.
Kon, Kenichi,Toyao, Takashi,Onodera, Wataru,Siddiki,Shimizu, Ken-Ichi
p. 2822 - 2827
(2017/07/28)

Noble metal-free catalytic decarboxylation of oleic acid to n-heptadecane on nickel-based metal-organic frameworks (MOFs)
Nickel based metal organic frameworks (Ni-MOFs) were successfully synthesized using new conjugated carboxylic acid linkers. These conjugated carboxylic acid linkers were synthesized using mild Heck coupling that led to the incorporation of functional groups not possible by traditional synthetic methods. Control of linker size allows for porosity tuning of the crystalline network and high surface area, that, in theory, results in the increased accessibility to Ni metal centers for catalysis. The resultant crystalline Ni-MOFs displayed BET areas as high as ～314 m2 g-1. To investigate their catalytic activity for conversion of oleic acid to liquid hydrocarbons, Ni-MOFs were grown on zeolite 5A beads that served as catalytic supports. The resultant catalysts displayed heptadecane selectivity as high as ～77% at mild reaction conditions, one of the highest yields for non-noble metal containing catalysts. The catalytic activity correlated to the concentration of acid sites. A slight decrease in catalytic activity was observed after catalysts recycling.
Yang,McNichols,Davidson,Schweitzer,Gómez-Gualdrón,Trewyn,Sellinger,Carreon
p. 3027 - 3035
(2017/08/01)

One-step hydroprocessing of fatty acids into renewable aromatic hydrocarbons over Ni/HZSM-5: Insights into the major reaction pathways
For high caloricity and stability in bio-aviation fuels, a certain content of aromatic hydrocarbons (AHCs, 8-25 wt%) is crucial. Fatty acids, obtained from waste or inedible oils, are a renewable and economic feedstock for AHC production. Considerable amounts of AHCs, up to 64.61 wt%, were produced through the one-step hydroprocessing of fatty acids over Ni/HZSM-5 catalysts. Hydrogenation, hydrocracking, and aromatization constituted the principal AHC formation processes. At a lower temperature, fatty acids were first hydrosaturated and then hydrodeoxygenated at metal sites to form long-chain hydrocarbons. Alternatively, the unsaturated fatty acids could be directly deoxygenated at acid sites without first being saturated. The long-chain hydrocarbons were cracked into gases such as ethane, propane, and C6-C8 olefins over the catalysts' Br?nsted acid sites; these underwent Diels-Alder reactions on the catalysts' Lewis acid sites to form AHCs. C6-C8 olefins were determined as critical intermediates for AHC formation. As the Ni content in the catalyst increased, the Br?nsted-acid site density was reduced due to coverage by the metal nanoparticles. Good performance was achieved with a loading of 10 wt% Ni, where the Ni nanoparticles exhibited a polyhedral morphology which exposed more active sites for aromatization.
Xing, Shiyou,Lv, Pengmei,Wang, Jiayan,Fu, Junying,Fan, Pei,Yang, Lingmei,Yang, Gaixiu,Yuan, Zhenhong,Chen, Yong
p. 2961 - 2973
(2017/02/05)

Controlling Hydrodeoxygenation of Stearic Acid to n-Heptadecane and n-Octadecane by Adjusting the Chemical Properties of Ni/SiO2–ZrO2 Catalyst
A series of SiO2–ZrO2 mixed oxides with varying SiO2 concentrations were hydrothermally synthesized and used as support for Ni in the hydrodeoxygenation of stearic acid. ZrO2 provides a relatively low surface area and only Lewis acid sites, and Ni supported on ZrO2 produces n-heptadecane from stearic acid through hydrogenation and decarbonylation. The SiO2–ZrO2 mixed oxides have a higher specific surface area than ZrO2 as well as an unprecedented spherical and nanolayered morphology. Br?nsted acid sites were created by the incorporation of SiO2 into ZrO2, promoting the hydrodeoxygenation activity of Ni and specifically opening a new reaction route to n-octadecane through the dehydration of 1-octadecanol intermediate into 1-octadecene with subsequent hydrogenation.
Foraita, Sebastian,Liu, Yue,Haller, Gary L.,Baráth, Eszter,Zhao, Chen,Lercher, Johannes A.
p. 195 - 203
(2017/01/17)

Effective conversion of heteroatomic model compounds in microalgae-based bio-oils to hydrocarbons over β-Mo2C/CNTs catalyst
Hydrotreatment of heteroatomic model compounds in microalgae-based bio-oils into diesel-like hydrocarbons was carried out over carbon nanotubes (CNTs)-supported β-Mo2C catalyst with superior activity and selectivity under a mild condition (≤200 °C). The results show that stearic acid and hexadecanamide can be completely converted into n-C15-C18 alkanes over β-Mo2C/CNTs catalyst. The β-Mo2CC/CNTs favors the pathway of hydrogenation-dehydration-hydrogenation to produce n-octadecane with an optimal yield of 91.24% at a lower temperature of 180 °C during hydrotreating process of stearic acid. The recycle tests demonstrate that the β-Mo2CC/CNTs exhibits excellent stability, and can be reused for seven times consecutively without reduction of catalytic stability. Based on the determined products, a brief reaction pathway is proposed. Therefore, a novel approach to produce diesel-like hydrocarbons via catalytic hydrotreatment of microalgae-based bio-oils over β-Mo2C/CNTs is introduced, which provides a basic research as well as technical parameters for its further industrialization.
Liang, Junmei,Ding, Ranran,Wu, Yulong,Chen, Yu,Wu, Kejing,Meng, Yongqiang,Yang, Mingde,Wang, Yaowu
p. 95 - 102
(2015/11/09)

Synthesis, structure and thermolysis of cis-dialkylplatinum(II) complexes - Experimental and theoretical perceptions
The formation of new C-C bonds by metal complexes always stimulates great interest because these fundamental reaction types possess numerous potential applications in organic synthesis. These reactions are well documented for a variety of transition metal complexes. Herein we report synthesis and characterization of a series of platinum-dialkyl complexes (1-10) of the type [Pt(L2)R2], (where L2 = dppp (1,3-bis(diphenylphosphino)propane or L = PPh3; R = n-butyl to n-nonyl) with a view to understand the organic product distribution patterns on thermolysis. The single crystal X-ray structures of the complexes [Pt(dppp){CH2(CH2)3CH3}2] (1) and [Pt(dppp){CH2(CH2)6CH3}2] (7) are reported. Thermal decomposition studies of these complexes show interesting behaviour; the longer chain dialkyls i.e. C7-C9 complexes undergo reductive elimination whereas the shorter chain dialkyl complexes and C3-C6 prefer only the β-hydride elimination reaction. Possible mechanistic aspects are discussed. Theoretical calculations reveal the strongest delocalizations in both complexes involve the interaction of Pt-C bond pair electron density with the trans positioned Pt-P antibonding orbital and vice-versa.
Venkatesh, Sadhana,Sravani, Chinduluri,Janardan, Sannapaneni,Suman, Pothini,Goud, E. Veerashekhara,Pavankumar,Leninkumar, Vardi,Bhat, Haamid R.,Sivaramakrishna, Akella,Vijayakrishna, Kari,Jha, Prakash C.,Smith, Gregory S.
p. 72 - 81
(2016/07/06)

Conversion of biomass-derived fatty acids and derivatives into hydrocarbons using a metal-free hydrodeoxygenation process
A metal-free hydrodeoxygenation process was developed for the production of hydrocarbons from biomass-derived fatty acids and derivatives. Biomass-derived fatty acids and derivatives were converted to alkanes and alkenes under mild reaction conditions. Furthermore, this catalytic system can also be applied to convert real biomass with satisfactory results.
Li, Xing-Yu,Shang, Rui,Fu, Ming-Chen,Fu, Yao
supporting information
p. 2790 - 2793
(2015/05/27)

Pd/Nb2O5/SiO2 catalyst for the direct hydrodeoxygenation of biomass-related compounds to liquid alkanes under mild conditions
A simple Pd-loaded Nb2O5/SiO2 catalyst was prepared for the hydrodeoxygenation of biomass-related compounds to alkanes under mild conditions. Niobium oxide dispersed in silica (Nb2O5/SiO2) as the support was prepared by the sol-gel method and characterized by various techniques, including N2 adsorption, XRD, NH3 temperature-programmed desorption (TPD), TEM, and energy-dispersive X-ray spectroscopy (EDAX) atomic mapping. The characterization results showed that the niobium oxide species were amorphous and well dispersed in silica. Compared to commercial Nb2O5, Nb2O5/SiO2 has significantly more active niobium oxide species exposed on the surface. Under mild conditions (170°C, 2.5 MPa), Pd/10 %Nb2O5/SiO2 was effective for the hydrodeoxygenation reactions of 4-(2-furyl)-3-buten-2-one (aldol adduct of furfural with acetone), palmitic acid, tristearin, and diphenyl ether (model compounds of microalgae oils, vegetable oils, and lignin), which gave high yields (>94 %) of alkanes with little C-C bond cleavage. More importantly, owing to the significant promotion effect of NbOx species on C-O bond cleavage and the mild reaction conditions, the C-C cleavage was considerably restrained, and the catalyst showed an excellent activity and stability for the hydrodeoxygenation of palmitic acid with almost no decrease in hexadecane yield (94-95 %) in a 150 h time-on-stream test.
Shao, Yi,Xia, Qineng,Liu, Xiaohui,Lu, Guanzhong,Wang, Yanqin
p. 1761 - 1767
(2015/06/02)

Decarboxylation of Oleic Acid to Heptadecane over Pt Supported on Zeolite 5A Beads
The synthesis of Pt supported on zeolite 5A beads for the decarboxylation of oleic acid to heptadecane is demonstrated. The use of a microporous ZIF-67 crystalline layer on zeolite 5A beads not only improved the heptadecane selectivity but also, most importantly, improved the stability of the resultant catalyst. Heptadecane yields as high as ～81% were observed for the fresh catalysts. The catalysts displayed only low to moderate loss of catalytic activity after two rounds of recycle. To our best knowledge, the catalytic performance of these catalysts is superior to those of the state-of-the-art catalysts at mild reaction conditions. In addition, as compared to powders, beads are much easier to recycle, can be fully recovered, and are more amenable for potential scale-up. The resultant catalysts are promising for the catalytic conversion of fatty acid molecules into gasoline/diesel-range hydrocarbons.
Yang, Liqiu,Tate, Kirby L.,Jasinski, Jacek B.,Carreon, Moises A.
p. 6497 - 6502
(2015/11/23)

Selective Catalytic Hydrogenolysis of Carbon-Carbon σ Bonds in Primary Aliphatic Alcohols over Supported Metals
The selective scission of chemical bonds is always of great significance in organic chemistry. The cleavage of strong carbon-carbon σ bonds in the unstrained systems remains challenging. Here, we report the selective hydrogenolysis of carbon-carbon σ bonds in primary aliphatic alcohols catalyzed by supported metals under relatively mild conditions. In the case of 1-hexadecanol hydrogenolysis over Ru/TiO2 as a model reaction system, the selective scission of carbon-carbon bonds over carbon-oxygen bonds is observed, resulting in n-pentadecane as the dominant product with a small quantity of n-hexadecane. Theoretical calculations reveal that the 1-hexadecanol hydrogenolysis on flat Ru (0001) undergoes two parallel pathways: i.e. carbon-carbon bond scission to produce n-pentadecane and carbon-oxygen bond scission to produce n-hexadecane. The removal of adsorbed CO on a flat Ru (0001) surface is a crucial step for the 1-hexadecanol hydrogenolysis. It contributes to the largest energy barrier in n-pentadecane production and also retards the rate for n-hexadecane production by covering the active Ru (0001) surface. The knowledge presented in this work has significance not just for a fundamental understanding of strong carbon-carbon σ bond scission but also for practical biomass conversion to fuels and chemical feedstocks.
Di, Lu,Yao, Sikai,Li, Mengru,Wu, Guangjun,Dai, Weili,Wang, Guichang,Li, Landong,Guan, Naijia
p. 7199 - 7207
(2015/12/11)

Highly Selective Hydrodecarbonylation of Oleic Acid into n-Heptadecane over a Supported Nickel/Zinc Oxide-Alumina Catalyst
The production of second-generation biodiesel with triglycerides or their derivatives through hydroprocessing is considered as a promising approach to make transportation fuels. In this study, a series of Ni-based catalysts supported on basic composite oxides (MO-Al2O3, M=Mg, Ca, Ni, Cu, Zn) were prepared for the catalytic deoxygenation of oleic acid in the presence of H2. Ni/ZnO-Al2O3 exhibited the highest deoxygenation activity and alkane selectivity, which depended on its moderate basicity. Investigations of the reaction conditions, which include reaction time, reaction temperature, H2 pressure, and Ni loading, suggested that n-heptadecane was the predominant product and its content increased with reaction temperature. The reaction temperature was more important than H2 pressure in the catalytic deoxygenation of oleic acid. Additionally, the overall reaction pathways for the conversion of oleic acid were proposed based on the product distribution for different durations and reaction rates of stearic acid, 1-octadecanol, and stearyl stearate, in which the oxygen atoms in the oleic acid were mainly removed in the form of CO through a hydrogenation-dehydrogenation-decarbonylation reaction route. If glycerol trioleate was used instead of oleic acid, Ni/ZnO-Al2O3 exhibited a high hydrodecarbonylation activity and selectivity to n-heptadecane.
Li, Guangci,Zhang, Feng,Chen, Lei,Zhang, Chuanhui,Huang, He,Li, Xuebing
p. 2646 - 2653
(2015/09/15)

Cu, Al and Ga based metal organic framework catalysts for the decarboxylation of oleic acid
Herein we demonstrate the catalytic decarboxylation and conversion of oleic acid to paraffins and hydrocarbons over bare and Pt supported Cu, Al and Ga based metal organic frameworks. Moderate degrees of decarboxylation were observed for all metal organic framework catalysts. The incorporation of Pt with the porous frameworks resulted in high degrees of decarboxylation. All MOF catalysts showed high thermal stability, resulting in recyclable catalysts displaying low catalytic activity loss. Of all studied catalysts, Ga-MOF catalysts were the most effective catalysts, displaying moderate to high degrees of decarboxylation. In addition, the Pt-Ga-MOF catalyst displayed selectivity to heptadecane, an important industrial chemical. Octadecane, heptadecane, dodecane, undecane, decane, nonane, octane, and heptane were observed as the main side products. To our best knowledge, the catalytic ability of a metal organic framework both as catalyst and support for the decarboxylation of a model fatty acid molecule is reported for the first time.
Yang,Ruess,Carreon
p. 2777 - 2782
(2015/07/22)

Effect of precursor acidity on zeolite supported Pd catalyst properties and hydrodeoxygenation activity for the production of biofuel
In this study, two different zeolite (ZLT) supported palladium catalysts (Pd/Zs) of varying acidity were synthesized, characterized and tested for biofuel production. The first Pd/Z was synthesized via the incorporation of palladium oxalate complex (PdOxC
Ayodele,Farouk, Hamisu U.,Mohammed, Jibril,Uemura, Yoshimitsu,Daud
p. 179 - 186
(2015/03/31)

Cationic pyridyl(benzoazole) ruthenium(II) complexes: Efficient and recyclable catalysts in biphasic hydrogenation of alkenes and alkynes
The synthesis, structural characterization of cationic 2-(2-pyridyl)benzoazole)ruthenium(II) complexes and their applications in biphasic hydrogenations of alkenes is reported. Reactions of 2-(2-pyridyl)benzoimidazole (L1), 2-(2-pyridyl)benzothiazole (L2) and 2-(2-pyridyl)benzoxazole (L3) with [η6-(2-phenoxyethanol)RuCl2]2produced the corresponding cationic complexes [η6-(2-phenoxyethanol)RuCl(L1)]Cl (1), [η6-(2-phenoxyethanol)RuCl(L2)]Cl (2) and [η6-(2-phenoxyethanol)RuCl(L3)]Cl (3) in good yields. Solid state structures of 1-3 confirmed the bidentate coordination modes of L1-L3 and formation of cationic species through displacement of one chloride ligand from Ru(II) coordination sphere. Complexes 1-3 produced active catalysts for high pressure hydrogenation of alkenes both in methanol and biphasic conditions. Relatively lower activities were observed in the hydrogenation of terminal alkynes giving a mixture of alkane and alkene products. Complexes 1-3 were recyclable under biphasic conditions and retained significant catalytic activities in six cycles. Reaction parameters such as substrate/catalyst ratio, temperature, and aqueous/organic ratio affected the catalytic trends.
Ogweno, Aloice O.,Ojwach, Stephen O.,Akerman, Matthew P.
p. 250 - 258
(2015/09/28)

Hydrodeoxygenation of fatty acids and triglycerides by Pt-loaded Nb2O5catalysts
Platinum nanoparticles loaded onto various supports have been studied for the selective hydrogenation of lauric acid to n-dodecane. The activity depends on the support material and pre-reduction temperature. Pt/Nb2O5reduced at 300 °C gives the highest activity. Pt/Nb2O5shows higher activity than various Nb2O5-supported transition metals (Ir, Re, Ru, Pd, Cu, Ni). Under solvent-free conditions Pt/Nb2O5is effective for the hydrodeoxygenation of lauric, capric, palmitic, myristic, oleic, and stearic acids under 8 bar H2at 180-250 °C, which gives high yields (88-100%) of linear alkanes with the same chain length as the starting compound. Tristearin is also converted to give 93% yield of n-octadecane. Pt/Nb2O5shows more than 60 times higher turnover number (TON) than the previously reported catalysts for the hydrogenation of stearic acid to n-octadecane. Mechanistic study shows a consecutive reaction pathway in which lauric acid is hydrogenated to 1-dodecanol, which undergoes esterification with lauric acid as well as hydrogenation to n-dodecane. The ester undergoes hydrogenolysis to give the alcohol, which is hydrogenated to the alkane. Infrared (IR) study of acetic acid adsorption on Nb2O5indicates that Lewis acid-base interaction of Nb cation and carbonyl oxygen, which suggests a possible role of Nb2O5as an activation site of carbonyl groups during hydrodeoxygenation. This journal is
Kon, Kenichi,Onodera, Wataru,Takakusagi, Satoru,Shimizu, Ken-Ichi
p. 3705 - 3712
(2015/04/14)

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel
Iron nanoparticles supported on mesoporous silica nanoparticles (Fe-MSN) catalyze the hydrotreatment of fatty acids with high selectivity for hydrodeoxygenation over decarbonylation and hydrocracking. The catalysis is likely to involve a reverse Mars-Van Krevelen mechanism, in which the surface of iron is partially oxidized by the carboxylic groups of the substrate during the reaction. The strength of the metal-oxygen bonds that are formed affects the residence time of the reactants facilitating the successive conversion of carboxyl first into carbonyl and then into alcohol intermediates, thus dictating the selectivity of the process. The selectivity is also affected by the pretreatment of Fe-MSN, the more reduced the catalyst the higher the yield of hydrodeoxygenation product. Fe-MSN catalyzes the conversion of crude microalgal oil into diesel-range hydrocarbons.
Kandel, Kapil,Anderegg, James W.,Nelson, Nicholas C.,Chaudhary, Umesh,Slowing, Igor I.
p. 142 - 148
(2014/05/20)

Catalytic production of 1-octadecanol from octadecanoic acid by hydrotreating in a plug flow reactor
1-Octadecanol (stearic alcohol) has uses ranging from lubricants to perfumes. The production of 1-octadecanol from octadecanoic acid (stearic acid) was investigated in a liquid-phase trickle-bed reactor by hydrogenating octadecanoic acid using a Ni/Co/Mo sulfide catalyst. The primary reactions occurring in the reactor were the desired conversion of octadecanoic acid to 1-octadecanol and the subsequent undesired conversion of 1-octadecanol to octadecane. A model was developed to predict these two reactions. The model found to be most useful for this system was a series-parallel reaction first order in octadecanoic acid and 1-octadecanol and pseudo-zero order in hydrogen for both reactions. The activation energies of the first and second reactions were 63.7.8 and 45.6 kJ/mol, respectively. From these values, the conversion of octadecanoic acid and the selectivity to the desired product as functions of temperature, space velocity, and inlet octadecanoic acid concentration were estimated. The model predicts the maximum productivity of 1-octadecanol occurs at higher temperatures with short residence times. Parametric plots show productivity to be ≥0.48 g 1-octadecanol/g octadecanoic acid at 566 °F and a 0.1 h residence time.
Potts, Thomas M.,Durant, Keiron,Hestekin, Jamie,Beitle, Robert,Ackerson, Michael
p. 1643 - 1650,8
(2014/11/07)

Molybdenum-mediated desulfurization of dhiols and disulfides
We have successfully achieved the molybdenum hexacarbonyl [Mo(CO) 6] mediated desulfurization of thiols and disulfides. In this reaction, the sulfhydryl (SH) mercapto groups of aryl, benzyl, primary and secondary alkyl thiols, and S-S single bonds of disulfides can be removed. This reaction has high functional group tolerance and is not affected by steric hindrance. The results of the reactions in acetone-d 6 suggest that the sources of hydrogen in the thiol and disulfide desulfurizations are the hydrogen atom(s) of a sulfhydryl group and acetone (solvent), respectively, and that the desulfurization proceeds via the formation of an organomolybdenum species. Georg Thieme Verlag Stuttgart. New York.
Wang, Zhen,Kuninobu, Yoichiro,Kanai, Motomu
supporting information
p. 1869 - 1872
(2014/08/18)

Role of support in deoxygenation and isomerization of methyl stearate over nickel-molybdenum catalysts
Microporous SAPO-11 and highly ordered mesoporous AlSBA-15 with different aluminum contents (with Si/Al ratio of 5 and 10) were synthesized. Thus prepared samples were characterized by BET, pyridine-FTIR and NH3-TPD to investigate their structural and acidic properties. The samples were then transformed into bifunctional catalysts by loading with molybdenum and nickel. Their activities were tested in the hydroconversion of methyl stearate using a fixed bed flow reactor system. The sulfided NiMo catalysts exhibited high conversion and deoxygenation activities. High isomerization activities observed for both NiMo/SAPO-11 and NiMo/AlSBA-15 catalysts, similar to the isomerization of light naphtha, was attributed to the acidity of supports. However, the acidity of supports was not the only factor influencing the isomerization of long chain molecules. AlSBA-15 had a large specific surface area that contained more acidic sites inside of its channels, promoting the formation of cracking products; SAPO-11 had a suitable pore size and contained fewer acidic sites inside the pore channels, promoting the formation of mono-branched isomers while suppressing cracking reactions.
Qian, Eika W.,Chen, Ning,Gong, Shaofeng
p. 76 - 85
(2014/04/03)

Kinetics of hydrodeoxygenation of stearic acid using supported nickel catalysts: Effects of supports
The hydrodeoxygenation of fatty acids derived from vegetable and microalgal oils is a novel process for production of liquid hydrocarbon fuels well-suited with existing internal combustion engines. The hydrodeoxygenation of stearic acid was investigated in a high pressure batch reactor using n-dodecane as solvent over nickel metal catalysts supported on SiO2, γ-Al2O3, and HZSM-5 in the temperature range of 533-563 K. Several supported nickel oxide catalysts with nickel loading up to 25 wt.% were prepared by incipient wetness impregnation method and reduced using hydrogen. The catalysts were then characterized by BET, TPR, H2 pulse chemisorption, TPD, XRD, and ICP-AES. Characterization studies revealed that only dispersed nickel oxide was present up to 15 wt.% nickel loading on γ-Al2O3. The acidity of the supports depends on nickel loading of oxidized catalysts and increases with increasing nickel loading up to 15 wt.%. n-Pentadecane, n-hexadecane, n-heptadecane, n-octadecane, and l-octadecanol were identified as products of hydrodeoxygenation of stearic acid with n-heptadecane being primary product. The catalytic activity and selectivity to products for hydrodeoxygenation of stearic acid depends strongly on acidity of the supports. The maximum selectivity to n-heptadecane was observed with nickel supported γ-Al2O3 catalyst. A suitable reaction mechanism of hydrodeoxygenation of stearic acid was delineated based on products distribution. The conversion of stearic acid was increased with increasing reaction time, nickel loading on γ-Al2O 3, temperature, and catalyst loading. Complete conversion of stearic acid was accomplished with more than 80% selectivity to n-heptadecane at reasonable reaction temperature of 563 K after 240 min of reaction using 15 wt.% Ni/γ-Al2O3 catalyst. An empirical kinetic model was also developed to correlate the experimental data.
Kumar, Pankaj,Yenumala, Sudhakara Reddy,Maity, Sunil K.,Shee, Debaprasad
p. 28 - 38
(2014/01/06)

Carbon nanofibers supported molybdenum carbide catalysts for hydrodeoxygenation of vegetable oils
Carbon nanofiber-supported molybdenum carbide catalysts (Mo 2C/CNF) with different loadings were prepared by the carbothermal hydrogen reduction method. Characterizations with Raman, XRD, N2-TGA, SEM, TEM and HAADF-STEM confirmed that Mo2C nanoparticles were successfully supported on the carbon nanofibers. The optimal reaction conditions with model compounds on Mo2C/CNF had a conversion of 98.03% and yield of 95.26%. It is interesting to note that a low evaporation rate positions the Mo2C nanoparticles on the outside of the CNF due to the capillary effect and the Mo2C nanoparticles on the outside of the CNFs showed high catalytic activity compared to ones on the inside of the CNFs. The Mo2C/CNF catalyst was recycled 5 times without any apparent loss of catalytic activity. Catalytic performances of Mo2C/CNF, Mo 2C/AC (activated carbon) and Mo2C/CNT (multi-walled carbon nanotubes) were examined using methyl palmitate and maize oil. The results showed that molybdenum carbide could be a potential substitute for noble metals in transformation of vegetable oils.
Qin, Yu,Chen, Ping,Duan, Jinzhao,Han, Junxing,Lou, Hui,Zheng, Xiaoming,Hong, Haiping
p. 17485 - 17491
(2013/09/24)

Effects of Si/Al ratio and Pt loading on Pt/SAPO-11 catalysts in hydroconversion of Jatropha oil
A series of Pt/SAPO-11 catalysts were prepared with various Si/Al ratios and Pt loadings and characterized by using BET, XRD, XRF, and CO pulse adsorption, as well as 29Si NMR and NH3-TPD techniques. Their catalytic performances in hydroconversion of Jatropha oil were tested with a fixed-bed flow reactor system. The isomerization activity increased with the Si/Al ratio because there were more medium acidic sites on the SAPO-11 supports. Pt/SAPO-11 catalysts with a Si/Al ratio of 0.4 demonstrated high activity for both deoxygenation and isomerization among catalysts with the same Pt loading. The deoxygenation, isomerization and cracking activities strongly depended on the Pt loading. The best activity was observed for the sample with a 3 wt% Pt loading, which generated an 83% yield of iso-C15-18 hydrocarbons under the LHSV of 0.5 h-1. Based on the mechanistic study of hydroconversion of methyl oleate, a reaction network for the hydroconversion of Jatropha oil was suggested.
Chen, Ning,Gong, Shaofeng,Shirai, Hisakazu,Watanabe, Toshitaka,Qian, Eika W.
p. 105 - 115
(2013/08/23)

Selective hydrogenation of alkenes under ultramild conditions
SiliaCat Pd0 solid catalyst heterogeneously mediates at room temperature the selective hydrogenation of a wide variety of alkenes under hydrogen balloon conditions using a modest 0.1 mol % catalyst amount. The catalyst is recyclable with negligible leaching of valued palladium, providing the chemical industry with a suitable replacement for less selective metal-based catalysts.
Pandarus, Valerica,Gingras, Genevieve,Beland, Francois,Ciriminna, Rosaria,Pagliaro, Mario
experimental part
p. 1230 - 1234
(2012/07/28)

Fe5C2 nanoparticles: A facile bromide-induced synthesis and as an active phase for Fischer-Tropsch synthesis
Iron carbide nanoparticles have long been considered to have great potential in new energy conversion, nanomagnets, and nanomedicines. However, the conventional relatively harsh synthetic conditions of iron carbide hindered its wide applications. In this
Yang, Ce,Hou, Yanglong,Zhao, Huabo,Ma, Ding
p. 15814 - 15821,8
(2020/08/24)

Permeable composite membrane as a catalytically active contactor for hydrogenation reactions
The efficiency of using of the permeable composite membrane (PCM) is demonstrated in the 3-phase reaction of liquid substrate with gaseous hydrogen on solid catalyst (PCM acts as a catalytically active contactor) - hydrogenation of fatty acid triglyceride. PCM provides a good combination of the opposite requirements of mild internal diffusion restrictions, low hydraulic resistance, high thermal conductivity, well-developed gas-liquid interface and high catalyst loading in the reactor volume, and thus assures the control of the course of the catalytic reaction.
Minyukova, T. P.,Shtertser, N. V.,Khassin, A. A.,Yurieva, T. M.
p. 107 - 110,4
(2020/08/20)

ISOMERIZATION OF LINEAR ALPHA-OLEFINS
Process for isomerizing linear alpha-olefins having from 10 to 25 carbon atoms over a heterogeneous catalyst.
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(2012/11/07)

PRODUCTION OF HYDROCARBON FUELS FROM PLANT OIL AND ANIMAL FAT
The present invention relates to fuel compositions and methods of making the same. The fuel compositions include hydrocarbon derived from a biological source selected from plant oil, animal fat and combinations thereof. The hydrocarbon and the fuel compositions are at least substantially oxygen-free. In particular, the fuel compositions are useful in cold temperature environments and as aviation fuel.
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Page/Page column 4

(2012/08/08)

Molybdenum carbide-catalyzed conversion of renewable oils into diesel-like hydrocarbons
In the paper, we report for the first time that the conversion of renewable oils into diesel-like hydrocarbon mixtures can be realized on molybdenum carbides with high activity and selectivity. The molybdenum carbide catalyst exhibited much better resistance to leaching than noble metals and could be reused consecutively for sixteen times without deactivation. Mechanism investigations indicated that molybdenum carbide and palladium showed different reaction selectivities and it was speculated that the level of difficulty in acyl-to-alkyl rearrangement of surface acyl intermediates on molybdenum carbide and palladium resulted in the different product selectivity. Copyright
Han, Junxing,Duan, Jinzhao,Chen, Ping,Lou, Hui,Zheng, Xiaoming
experimental part
p. 2577 - 2583
(2011/12/01)

Decarboxylation of fatty acids over Pd supported on mesoporous carbon
Fatty acid decarboxylation was studied in a semibatch reactor over 1 wt.% Pd/C (Sibunit) using five different fatty acids, C17-C20 and C22, as feeds. The same decarboxylation rates were obtained for pure fatty acids, whereas extensive catalyst poisoning and/or sintering and coking occurred with low purity fatty acids as reactants. One reason for catalyst poisoning using behenic acid (C22) as a feedstock was its high phosphorus content. The decarboxylation rate of fatty acids decreased also with increasing fatty acid to metal ratio.
Simakova, Irina,Simakova, Olga,M?ki-Arvela, P?ivi,Murzin, Dmitry Yu.
experimental part
p. 28 - 31
(2010/11/16)

Palladium-catalyzed decarboxylation of higher aliphatic esters: Towards a new protocol to the second generation biodiesel production
An effective and highly selective decarboxylation approach to convert higher aliphatic esters into diesel-like paraffins has been developed. The results showed that palladium supported on barium sulfate was a potent catalyst to transform aliphatic esters into high-energy alkanes in supercritical hexane at a much lower temperature. Based on the comprehensive analysis to gas and liquid products, a decarboxylation mechanism was proposed. The methodology described in this paper provides a new protocol to the utilization of biomass-based resources, especially to the second generation biodiesel production.
Han, Junxing,Sun, Hui,Ding, Yuqi,Lou, Hui,Zheng, Xiaoming
experimental part
p. 463 - 467
(2010/08/06)

Efficient heterogeneous dual catalyst systems for alkane metathesis
A fully heterogeneous and highly efficient dual catalyst system for alkane metathesis (AM) has been developed. The system is comprised of an alumina-supported iridium pincer catalyst for alkane dehydrogenation/olefin hydrogenation and a second heterogeneous olefin metathesis catalyst. The iridium catalysts bear basic functional groups on the aromatic backbone of the pincer ligand and are strongly adsorbed on Lewis acid sites on alumina. The heterogeneous systems exhibit higher lifetimes and productivities relative to the corresponding homogeneous systems as catalyst/catalyst interactions and bimolecular decomposition reactions are inhibited. Additionally, using a two-pot device, the supported Ir catalysts and metathesis catalysts can be physically separated and run at different temperatures. This system with isolated catalysts shows very high turnover numbers and is selective for the formation of high molecular weight alkanes.
Huang, Zheng,Rolfe, Eleanor,Carson, Emily C.,Brookhart, Maurice,Goldman, Alan S,El-Khalafy, Sahar H.,Roy MacArthur, Amy H.
experimental part
p. 125 - 135
(2010/06/20)