Copper oxide, propylene oxidation

Copper high Miller index, 26 12 Copper oxide, 27 184-187, 199 as adsorbent, 21 44 on alumina, 27 80-85 -manganese oxide, 27 91, 92 oxidation of CO over, 24 86 -platinum catalyst, 27 86-88 propylene oxidation, 30 141 Coprecipitation, perovskite preparation, 36 247-250... 

Fig. 7. Experimental propylene oxidation activity vs. catalyst oxidation state-copper oxide catalyst. Reaction temperature = 300°C. From (6). 

In this work the catalytic activity of a series of copper oxide catalysts supported on monolithic honeycomb supports in the reduction of nitrogen oxide with propylene in an oxidising atmosphere was studied. The monoliths were produced from acid washed sepiolite, sepiolite or a mixture of sepiolite and alumina in order to study the effect of the support on the activities and selectivities of the catalysts. Tlie introduction of nickel oxide as a second active species on the overall activity was also detennined. Finally tlie application of an alumina washcoat impregnated with the copper and nickel salts to increase the accessibility of tlie gases to be treated to the active phase was studied. 

A very different picture of propylene oxidation kinetics over a copper oxide catalyst was presented by Billingsley and Holland 102) who, on the basis of a differential reactor study at 240°, concluded that the reaction was limited by mass transfer of the oxygen, and proposed the following rate equations ... 

Early catalysts for acrolein synthesis were based on cuprous oxide and other heavy metal oxides deposited on inert siHca or alumina supports (39). Later, catalysts more selective for the oxidation of propylene to acrolein and acrolein to acryHc acid were prepared from bismuth, cobalt, kon, nickel, tin salts, and molybdic, molybdic phosphoric, and molybdic siHcic acids. Preferred second-stage catalysts generally are complex oxides containing molybdenum and vanadium. Other components, such as tungsten, copper, tellurium, and arsenic oxides, have been incorporated to increase low temperature activity and productivity (39,45,46). 

Two options are being developed at the moment. The first is to produce 1,2-propanediol (propylene glycol) from glycerol. 1,2-Propanediol has a number of industrial uses, including as a less toxic alternative to ethylene glycol in anti-freeze. Conventionally, 1,2-propanediol is made from a petrochemical feedstock, propylene oxide. The new process uses a combination of a copper-chromite catalyst and reactive distillation. The catalyst operates at a lower temperature and pressure than alternative systems 220°C compared to 260°C and 10 bar compared to 150 bar. The process also produces fewer by-products, and should be cheaper than petrochemical routes at current prices for natural glycerol. The first commercial plant is under construction and the process is being actively licensed to other companies. 

Propylene oxide F T Steel or stainless steel Rubber preferred though copper and brass are suitable for acetylene-free gas PTFE gaskets... 

The reaction of olefin epoxidation by peracids was discovered by Prilezhaev [235]. The first observation concerning catalytic olefin epoxidation was made in 1950 by Hawkins [236]. He discovered oxide formation from cyclohexene and 1-octane during the decomposition of cumyl hydroperoxide in the medium of these hydrocarbons in the presence of vanadium pentaoxide. From 1963 to 1965, the Halcon Co. developed and patented the process of preparation of propylene oxide and styrene from propylene and ethylbenzene in which the key stage is the catalytic epoxidation of propylene by ethylbenzene hydroperoxide [237,238]. In 1965, Indictor and Brill [239] published studies on the epoxidation of several olefins by 1,1-dimethylethyl hydroperoxide catalyzed by acetylacetonates of several metals. They observed the high yield of oxide (close to 100% with respect to hydroperoxide) for catalysis by molybdenum, vanadium, and chromium acetylacetonates. The low yield of oxide (15-28%) was observed in the case of catalysis by manganese, cobalt, iron, and copper acetylacetonates. The further studies showed that molybdenum, vanadium, and... 

The more expedient, direct catalytic oxidation route to acetone was developed in Germany in the 1960s. If you had been in charge of building the acetone business from scratch, you d probably not have built any IPA-to-acetone plants if you had known about the Wacker process. It s a catalytic oxidation of propylene at 200—250°F and 125—200 psi over palladium chloride with a cupric (copper) chloride promoter. The yields are 91-94%. The hardware for the Wacker process is probably less than for the combined IPA/acetone plants. But once the latter plants were built, the economies of the Wacker process were not sufficient to shut them down and start all over. So the new technology never took hold in the United States. 

Some of the results obtained by Ben-Taarit et al. for propylene oxidation on Cu2+Y are similar to those reported by Mochida et al. when an excess of propylene is used in the feed [2]. The former authors stress that under these circumstances Cu+2 in Cu +Y is transformed to a Cu°/Cu20/Cu0 mixture. However, using optimized 02/propylene ratios, flow rates and temperatures, it seems that 70% selectivity for acrolein at 50% propylene conversion is achievable. Under those conditions there was no evidence for the formation of either a metallic or an oxide copper phase [2]. 

Epichlorohydrin Epoxidized Vegetable Oils Epoxidized Vegetable Oils Octyl Epoxy Tallate Epoxidized Vegetable Oils Butylene Oxide Ethylene Oxide Propylene Oxide Sodium Nitrite Copper Chloride Trichloiofluoromethane Dichlordifluoromethane Monochlorodifluoromediane Nitrobenzene Acetaldehyde Ethane... 

A second report of organic carbonate production from epoxide and C02 utilizes copper(I) cyanoacetate, Cu(02CCH2CN), as a carrier of activated C02 (158). Reaction of propylene oxide with Cu(02CCH2CN) at 130°C for 10 hours yields propylene carbonate in 83% yield, based on the... 

Propylene oxide is one of the raw materials used to manufacture rubbery and crystalline polyepoxides. R. J. Herold and R. A. Livigni describe propylene oxide polymerization with hexacyanometalate salt complexes as catalyst. Polyphenylene oxide is made by copper catalyzed oxidative coupling of 2,6-dimethylphenol. G. D. Cooper, J. G. Bennett, and A. Factor discuss the preparation of copolymers of PPO by oxidative coupling of dimethylphenol with methylphenylphenol and with diphenylphenol. 

Together with A. DiSpirito of Iowa State University, we conducted in 2007 a Mossbauer study of pMMO from M. capsulatus (Bath), aimed at determining whether the (quite active) preparations contained iron components assignable to a catalytically active site.44 Before we discuss the Mossbauer spectra, a comment about MMO catalytic activity will be in order. Biochemists have developed a propylene oxidation assay, and the MMO activity is measured in units of nmol propylene oxide/min/mg protein.45 The activities of pMMO samples investigated by us had 1500 units in whole cells, 500 units in membrane fractions (with the enzyme residing still in the membrane), and 160 units for the purified enzyme. Preparations from laboratories favoring a copper catalytic site have <20 units or no activ-ity.33,34,38 39 46 47 The above values show that catalytic activity is lost in the course of the preparation, either by loss of metals from the active site or by conformational changes not yet appreciated. 

Copper compounds are catalysts for the Michael addition reaction (249), olefin dimerizations (245, 248), the polymerization of propylene sulfide (142), and the preparation of straight-chain poly phenol ethers by oxidation of 2,6-dimethylphenol in the presence of ethyl- or phenyl-copper (209a). Pentafluorophenylcopper tetramer is an intriguing catalyst for the rearrangement of highly strained polycyclic molecules (116). The copper compound promotes the cleavage of different bonds in 1,2,2-tri-methylbicyclo[1.1.0]butane compared to ruthenium or rhodium complexes. Methylcopper also catalyzes the decomposition of tetramethyllead in alcohol solution (78, 81). 

The oxidation of propylene has been chosen as a probe reaction to study the catalytic activity of Cu Pd -TSM. The olefin oxidation in an acidic solution of Cu(II) and Pd(U) chlorides, well known as the Wacker reaction, is achieved when olefins are selectively oxidized to ketones or aldehydes by hydrated Pd, leaving Pd . The Pd is oxidized back to Pd by 2Cu, and the resulting Cu is reoxidized by dissolved oxygen. Because the corrosive nature of the catalyst solution is a serious disadvantage for practical use, supported copper-palladium catalysts have been proposed to operate the reaction in a gas flow reactor (40). 

Propylene oxide is extremely flammable. Propylene oxide-air mixtures may be explosive by contact with heat or by ignition. Propylene oxide is incompatible with acids, bases, oxidizing agents, polymerization catalysts, epoxy resins, and high temperatures. It reacts violently with acetylide-forming metals such as copper or copper alloys. 

Methacrylates with pendant oxyethylene units (FM-19) were polymerized in a controlled way with metal catalysts in the bulk or in water. The catalytic systems include a bromide initiator coupled with Ni-2 for n = 2 (bulk, 80 °C)319 and CuCl for n = 7-8.246-320 The latter polymerization proceeded very fast in aqueous media at 20 °C to reach 95% conversion in 30 min and gave very narrow MWDs (MJMn =1.1 — 1.3). The fast reaction is attributed to the formation of a highly active, monomeric copper species com-plexed by the oxyethylene units. A statistical copolymerization of FM-19 (n = 7—8) and FM-20, a methacrylate with a oligo (propylene oxide) pendant group, led to hydrophilic/hydrophobic copolymers with narrow MWDs (MwIMn = 1.2).320... 

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