Renewable linear alpha olefins by selective ethenolysis of decarboxylated unsaturated fatty acids

A two‐step concept for the production of linear alpha olefins from biomass is reported. As a starting material an internally unsaturated C17 alkene was used, which was obtained by the decarboxylation of oleic acid. Here, we report on the ethenolysis of this bio‐based product, using commercially available metathesis catalysts. The desired alpha olefin products, 1‐nonene and 1‐decene, were obtained in excellent yield (96%) and selectivity (96%). Practical applications: The two‐step conversion described in this contribution, starting from unsaturated fatty acids, provides a method for the production of industrially important linear alpha olefins. These valuable products are widely used as starting materials for the production of surfactants and polymers such as linear low density polyethylene (LLDPE).     

Ruthenium carbonyl-complex catalyzed hydroaminomethylation of olefins with carbon dioxide and amines

Use of carbon dioxide as a reactant instead of toxic carbon monoxide in the hydroaminomethylation reaction sequence is demonstrated for the first time. The present Ru₃(CO)₁₂-catalyzed one-pot protocol includes reverse-water–gas-shift (RWGS) reaction, hydroformylation reaction and reductive amination which finally leads to secondary and tertiary amine. The influence of various reaction parameters including the effects of catalytic promotors and phase-transfer-catalysts has been investigated. Finally, an optimum reaction conditions were found by suppressing the major side products to have a variety of amines in excellent yields (up to 98%).     

Ruthenium complex-catalyzed hydroformylation of alkenes with carbon dioxide

Carbon dioxide can be used as a reactant for the hydroformylation of alkenes. The ruthenium complexes derived from H₄Ru₄(CO)₁₂ and LiCl effectively catalyze the hydroformylation of cyclohexene with CO₂ to give hydroxymethylcyclohexane with a yield of 88%.     

Catalytic deoxygenation of unsaturated renewable feedstocks for production of diesel fuel hydrocarbons

The liquid-phase deoxygenation reaction of unsaturated renewables has been investigated in a semi-batch reactor. The reactants examined were the monounsaturated fatty acid, oleic acid, the diunsaturated fatty acid, linoleic acid and the monounsaturated fatty acid ester, methyl oleate. The reactions were carried out over a Pd/C catalyst under constant pressure and temperature in the following domain, 15-27 bar and 300-360 °C, respectively. The influence of carrier gas was additionally investigated. The impact as solvent (mesitylene) was studied as well and reaction pathways were proposed. Furthermore, continuous deoxygenation experiments were conducted, facilitating understanding of the catalyst stability and catalyst deactivation. The deoxygenation catalyst was characterized by physisorption, temperature programmed desorption (TPD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM).     

三氯化钌的回收

本文着重介绍了从熔融法去除金属阳极旧电极涂层的熔盐中回收贵金属钌,并直接制备出适于阳极涂层的β-RuCl_3.xH_2O。     

A personal view on homogeneous catalysis and its perspectives for the use of renewables

This personal account is based on a talk at the conference “Fats and Oils as Renewable Feedstock for the Chemical Industry” in Emden, Germany. It describes selected perspectives and challenges applying catalysis for the refinement of renewables. Because the author himself has not been active in the past using biomass‐based starting materials, special focus is given on the use of homogeneous catalysis as a tool for a more sustainable chemistry in industry and academia. Recent developments of catalysts in our research group are used to illustrate the current status and challenges of homogeneous catalysis in this area.     

Ruthenium electrodeposition on silicon from a room-temperature ionic liquid

Electrochemical deposition of ruthenium on n-type silicon from an ionic liquid is reported for the first time. The study was performed by dissolving ruthenium(III) chloride in a 1-butyl-3-methyl imidazolium hexafluorophosphate (BMIPF₆) room-temperature ionic liquid (RTIL). Cyclic voltammetry (CV) studies demonstrate reduction and stripping peaks at −2.1 and 0.2 V vs. Pt quasi-reference, corresponding to the deposition and dissolution of ruthenium, respectively. Metallic Ru films of ∼100 nm thickness have been deposited and were analyzed using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).     

Homogeneous metathesis for the production of propene from butene

The cross-metathesis of 1-butene and 2-butene is described for the production of propene and 2-pentene using Phobcat, a homogeneous Grubbs first generation-type catalyst bearing 9-cyclohexyl-9-phosphabicyclo-[3.3.1]-nonane as ligand. In a closed system at 20 bar and 50 °C, the reaction mixture composition at different 1-butene:2-butene feed ratios is in fair agreement with the calculated composition at equilibrium based on thermodynamic data. Compared to heterogeneous metathesis over a WO₃/SiO₂ catalyst, the homogeneous reaction exhibits better reaction control and selectivity to the desired products.     

Ruthenium catalyzed chemical modification of unsaturated polymers

Summary Chemical modification of unsaturated polysiloxanes with pendant or terminal vinyl groups and polycarbosilanes with pendant Si-vinyl groups has been achieved by a novel ruthenium catalyzed reaction. Dihydridocarbonyltris(triphenylphosphine)-ruthenium catalyzes the addition of the ortho C–H bond of 2-methylacetophenone across the C–C double bond of pendant or terminal vinyl groups of polymers such as copoly(dimethylsiloxane/vinylmethylsiloxane), polydimethylsiloxane which is terminated with vinyldimethylsiloxy groups and copoly(vinylmethylsilylene/1,4-phenylene).     

Optimal integrated energy systems design incorporating variable renewable energy sources

The effect of variability in renewable input sources on the optimal design and reliability of an integrated energy system designed for off-grid mining operation is investigated via a two-stage approach. Firstly, possible energy system designs are generated by solving a deterministic non-linear programming (NLP) optimization problem to minimize the capital cost for a number of input scenarios. Two measures of reliability, the loss of power supply probability (LPSP) and energy index of reliability (EIR), are then evaluated for each design based on the minimization of the external energy required to satisfy load demands under a variety of input conditions. Two case studies of mining operations located in regions with different degrees of variability are presented. The results show that the degree of variability has an impact on the design configuration, cost and performance, and highlights the limitations associated with deterministic decision making for high variability systems.     

Improvement of Lubricant Materials Using Ruthenium Isomerization

Production of an effective industrial lubricant additive from vegetable oils is a high profile and difficult undertaking. One candidate is alkyl 9(10)-dibutylphosphonostearate, which has been made through a radical transformation of alkyl 9-cis-octadecanoate. It is effective, but still suffers from drawbacks. In this report, that synthesis is combined with a ruthenium based isomerization process to create not just one, but an entire series of new chemical compounds. A low level of [Ru(CO)₂(EtCO₂)]_n is first used for the isomerization of the starting material, then radical chemistry is employed. A series of methyl dibutylphosphonooctadecanoates was made. In an analogous fashion, trans-7-tetradecene was also isomerized and then polymerized. As in the phosphonate case, the follow-up chemistry could be performed in the presence of the residual isomerization catalyst. The alkane:alkene ratio, observed by ¹H NMR, was found to change from 14:1 in the isomerized starting material to a value of 41:1 in the polymerized material. This methodology, isomerization in tandem with other reactions, gives suitable routes to both biobased polyolefins, and biobased phosphonates, potential key ingredients in biobased lubrication formulations.     

钌基氨合成催化剂的活性影响因素研究

钌基催化剂被称为第二代合成氨催化剂,本文分析了影响钌基催化剂活性的主要因素,如还原温度、载体、活性组分、促进剂等,为开发和研制钌基氨合成催化剂提供参考.     

Innovative Process for the Synthesis of Nanostructured Ruthenium Catalysts and their Catalytic Performance

An efficient, reproducible process for the solvothermal synthesis of Ru/γ-Al₂O₃ nanocatalysts has been developed. This synthesis employs a low boiling point alcohol acting as solvent and reducing agent. The reaction is performed in autoclave under nitrogen overpressure, by heating the solution of metal precursor and stabilizing agent in the presence of the support. These systems show very promising performances, also with an application perspective, in the selective hydrogenation of phenol to cyclohexanone carried out at 160 °C under 5 MPa of hydrogen: a selectivity to cyclohexanone as high as 83% has been reached at a phenol conversion value of 88%. This paper is dedicated to the memory of Professor Carlo Carlini, with great sorrow.     

浅电子陷阱掺杂剂——Ru(Ⅱ)的应用研究

研究了浅电子陷阱掺杂剂———钌盐Ru (Ⅱ )加入纯溴立方体乳剂中 ,对感光度的影响 ,结果表明在乳剂颗粒的一定位置 ,掺杂一定量钌盐能明显提高乳剂感光度。     

Liquid-Liquid Extraction of Ruthenium from Chloride Media by N,N'-Dimethyl- N,N'-Dicyclohexylmalonamide

Abstract

Research on the solvent extraction of ruthenium from hydrochloric acid media has been carried out using N,N'-dimethyl-N,N'-dicyclohexylmalonamide (DMDCHMA) dissolved in 1,2-dichloroethane. Ruthenium extraction percentages (%E) ranging from 50% to 80% have been achieved for HCl concentrations between 5 M and 7 M. Extraction curves exhibiting the dependence of the %E ruthenium on HCl concentration in the aqueous phases are presented, the latter solutions being obtained by dissolution of either Ru(III) or Ru(IV) salts. The influence of some experimental parameters on the %E Ru, such as the equilibration time, extractant concentrations, and hydrogen-ion activities, has been thoroughly investigated. Additionally, DMDCHMA is also adequate for extracting Pd(II) from 5 M to 7 M HCl solutions and under similar experimental conditions, %E Rh(III) is below 5%, and Pt(IV), Ir(III), and Ir(IV) cause the formation of third phases. Both Ru and Pd(II) can be successfully stripped from the loaded organic phases with water. A partition scheme to isolate Ru from a number of some associated elements has also been attempted.     

An Ionic Liquid as Catalyst Medium for Stereoselective Hydrogenations of Sorbic Acid with Ruthenium Complexes

The ionic liquid 1‐n‐butyl‐3‐methylimidazolium hexafluorophosphate (bmim PF₆) ( 6 ) has been studied as catalyst medium for biphasic homogeneous hydrogenations of sorbic acid ( 1 ). As catalyst we used the Cp*‐ruthenium‐complex [Cp*Ru(η⁴‐CH₃—CHCH—CHCH—COOH) (CF₃SO₃)] which efficiently enables the stereoselective hydrogenation of sorbic acid leading to the formation of cis‐3‐hexenoic acid ( 3 ) in selectivities of up to 90% with turnover frequencies of up to 1100 h^—1. Compared to other biphasic systems the hydrogenation in bmim PF₆ proceeds with enhanced activity. The kinetics can be described with a Michaelis Menten‐equation, and the activation energy for the whole process was determined to be E_A = 78 ± 5 kJ/mol.     

Ruthenium Nanocatalysts for Ammonia Synthesis: A Review

Despite technological developments within the past century, ammonia synthesis from nitrogen and hydrogen is still highly energy intensive due to high-pressure operation. Even with recently introduced Ru-based catalysts with superior performance over conventional iron-based catalysts, there is still room for improvements to approach the theoretical minimum energy consumption. A novel approach is to use nanostructured components in catalyst formulation. Reducing Ru crystallite size to nanometers could greatly increase catalytic activity by increasing surface area as well as by the structure sensitivity of ammonia synthesis over Ru-based catalysts due to the increase of the density of highly active B₅ sites. The control of Ru particle size and shape in the nanometer range and stabilization of the particles by appropriate innovative preparation techniques are key factors for development of commercial Ru nanocatalysts. Theoretical and experimental studies on actives sites and metal-promoter and metal-support interactions by advanced computational and characterization methods are also essential.     

Extraction of a Homogeneous Rhodium Catalyst from Saturated Branched Fatty Derivatives

Saturated branched fatty derivatives are of great interest for the lubricants and cosmetics industry due to their improved temperature and viscosity behavior compared to the corresponding linear homologues. One way to produce saturated branched derivatives is the homogeneous rhodium‐catalyzed conjugation and co‐oligomerization of linoleic compounds based on renewable resources, e.g., sunflower oil, with ethene. The catalyst extraction behavior of the homogeneous rhodium catalyst RhCl₃·3H₂O from saturated branched fatty derivatives for catalyst recycling was studied. Investigation of the extraction parameters was performed using the model substance isostearic acid. Additionally, extraction of rhodium from co‐oligomer mixtures with different grade of saturation was carried out successfully. Also, the influence of solvent residues from prior reaction steps was evaluated.     

A modeling framework for design of nonlinear renewable energy systems through integrated simulation modeling and metaheuristic optimization: Applications to biorefineries

This study presents the development and implementation of a novel framework for optimal design of new and emerging renewable energy production systems by considering an iterative strategy which integrates the Net Present Value optimization along with detailed mechanistic modeling, simulation, and process optimization which yields optimal capacity plan, and operating conditions for the process. Due to the non-linear nature of process conversion mechanisms, metaheuristic algorithms are implemented in the framework to optimize operating conditions of process. Further, to apply complex kinetics in the process, we have made a linkage between process simulator (Aspen Plus) and Matlab. To demonstrate the effectiveness of the proposed methodology, a hypothetical case study of a lignocellulosic biorefinery is utilized. The proposed framework results reveal a deviation in optimal process yields and production capacities from initial literature estimates. These results indicate the importance of developing a multi-layered framework to optimally design a renewable energy production system.