Liquid phase catalytic processing

Christopher Hardacre read natural sciences at the University of Cambridge, where he also obtained his PhD in 1994. He was appointed to a lectureship in physical chemistry at the Queen s University of Belfast in 1995 and in 2003, he became a professor of physical chemistry. He is currently director of research in CenTACat, and his current interests include the understanding of gas and liquid phase catalytic processes for emission control, clean energy production, and fine chemical synthesis as well as the study and use of ionic liquids. 

Chheda JN, Huber GW, Dumesic JA. Liquid-phase catalytic processing of biomass-derived oxygenated hydrocarbons to fuels and chemicals. Angew Chem Int Ed. 2007 46 (38) 7164—83. 

Ameise and Kutz [40] described a patented catalytic process to isomerize a mixture of xylenes to a product stream enriched in p-xylene at conditions over the critical point of the mixture. Supercritical operation provided enhanced catalyst activity compared to the conventional liquid phase catalytic process that operated at lower temperatures. Moreover, operating at supercritical conditions reduced catalyst deactivation compared to the gas phase reaction. Reduced catalyst deactivation allowed elimination of the H2 and related compression equipment that was required to maintain catalyst activity in the gas phase process. 

Liquid phase catalytic processing is a promising biorefinery process that produces functionalized hydrocarbons from biomass-derived intermediates (e.g., intermediate hydroxymethylfurfural or HMF). Renewable furan derivatives can be used as substitute building blocks for fossil fuels, plastics, and fine chemicals, ° or to develop biofuels based on C5 and C6 carbohydrates (sugars, hemicellulose, cellulose). Currently, Avantium Chemicals in the Netherlands is developing chemical catalytic routes to generate furanics for renewable polymers, bulk and specialty chemicals, and biofuels. ... 

The results of the present study show that it would be mistake to consider carbon siQ>ports as an inert matrix and much attention should be payed to both physical and chemical characteristics of these sv5)ports. In particular, the very rich chemistry of the carbon surface provides conditions for strong anchoring of metal complexes by such a simple technique as adsorption and the heterogenized species ml t be used in liquid-phase catalytic processes. If these species are taken as a precursor for metal crystallites, the state and properties of final metal particles can be Influenced to a great extent by the nature of initial complex and technique of its deposition. ... 

O.M.Ilinich, Basic Principles of Action of Polymeric Membranes in Liquid Phase Catalytic Processes and Separations of Gaseous Mixtures, Boreskov Institute of Catalysis, Novosibirsk, 1997 (Russian). 

The Acetaldehyde Oxidation Process. Liquid-phase catalytic oxidation of acetaldehyde (qv) can be directed by appropriate catalysts, such as transition metal salts of cobalt or manganese, to produce anhydride (26). Either ethyl acetate or acetic acid may be used as reaction solvent. The reaction proceeds according to the sequence... 

The TS-1 catalysed hydroxylation of phenol to a 1 1 mixture of catechol and hydroquinone (Fig. 2.16) was commercialized by Enichem (Romano et ai, 1990). This process offers definite advantages, such as higher selectivities at higher phenol conversions, compared to other catalytic systems. It also illustrates another interesting development the use of solid, recyclable catalysts for liquid phase (oxidation) processes to minimize waste production even further. 

Catalytic dehydrogenation of alcohol is an important process for the production of aldehyde and ketone (1). The majority of these dehydrogenation processes occur at the hquid-metal interface. The liquid phase catalytic reaction presents a challenge for identifying reaction intermediates and reaction pathways due to the strong overlapping infrared absorption of the solvent molecules. The objective of this study is to explore the feasibility of photocatalytic alcohol dehydrogenation. 

Noncatalytic oxidation to produce acetic acid can be carried out in the gas phase (350-400°C, 5-10 atm) or in the liquid phase (150-200°C). Liquid-phase catalytic oxidations are operated under similar mild conditions. Conditions for the oxidation of naphtha are usually more severe than those for n-butane, and the process gives more complex product mixtures.865-869 Cobalt and other transition-metal salts (Mn, Ni, Cr) are used as catalysts, although cobalt acetate is preferred. In the oxidation carried out in acetic acid solution at almost total conversion, carbon oxides, carboxylic acids and esters, and carbonyl compounds are the major byproducts. Acetic acid is produced in moderate yields (40-60%) and the economy of the process depends largely on the sale of the byproducts (propionic acid, 2-butanone). 

Allied-Signal Process. Cyclohexanone [108-94-1] is produced in 98% yield at 95% conversion by liquid-phase catalytic hydrogenation of phenol. Hydroxylamine sulfate is produced in aqueous solution by the conventional Raschig process, wherein NO from the catalytic air oxidation of ammonia is absorbed in ammonium carbonate solution as ammonium nitrite (eq. 1). The latter is reduced with sulfur dioxide to hydroxylamine disulfonate (eq. 2), which is hydrolyzed to acidic hydroxylamine sulfate solution (eq. 3). 

BASF. In the Badische process, cyclohexanone is produced by liquid-phase catalytic air oxidation of cyclohexane to KA oil, which is a mixture of cyclohexanone and cydohexanol, and is followed by vapor-phase catalytic dehydrogenation of the cydohexanol in the mixture. Overall yidds range from 75% at 10% cydohexane conversion to 80% at 5% cydohexane conversion. 

The present work reports on results of the liquid-phase catalytic hydrogenation of butynediol on supported nickel catalysts specifically tailored for these processes. In this respect, we have studied support effects, the influence of nickel loading as well as the influence of Cu as a second metal. 

Co saturated hydrocarbons are used extensively in the United States, whereas the acetylene process was used almost exclusively in Europe until recently. These processes were extended by the late 1950 s and early 1960 s by a new approach called the Wacker process or the Wacker-Hoechst process, consisting of the liquid phase catalytic oxidation of ethylene to acetaldehyde, as outlined in Table II. 

Whatever metal is used, homogeneous processes suffer from high cost resulting from the consumption of the catalyst, whether recycled or not. This is why two-phase catalytic processes have been developed such as hydroformylation catalyzed by rhodium complexes, which are dissolved in water thanks to hydrophilic phosphines (cf. Section 3.1.1.1) [17]. Due to the sensitivity of most dimerization catalysts to proton-active or coordinating solvents, the use of non-aqueous ionic liquids (NAILs) as catalyst solvents has been proposed. These media are typically mixtures of quaternary ammonium or phosphonium salts, such as 1,3-dialkylimi-dazolium chloride, with aluminum trichloride (cf. Section 3.1.1.2.2). They prove to be superb solvents for cationic active species such as the cationic nickel complexes which are the active species of olefin dimerization [18, 19]. The dimers. 

Process improvements in the manufacture of aniline have been driven by tremendous demand, particularly from the rubber industry, and for use in the manufacture of isocyanates for polyurethanes, dyestuffs, sulfa drugs, agrochemicals, and detonators and stabilizers for explosives. Two widely used catalytic processes have been developed, one vapor phase, the other liquid phase. Both processes are highly exothermic, and the exchange and use of heat is important4. 

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