Copper flow reactor

A library of 1,4-disubstituted 1,2,3-triazoles was synthesized at Cornell University in collaboration with Pfizer Inc. [47]. Six different acetylenes, six different alkyl halides, and sodium azide were used for obtaining the triazoles. Thirty triazoles were synthesized in a continuous-flow Conjure reactor (a copper flow reactor) in good... 

Reactions could be easily scaled up with fewer safety concerns than the corresponding batch processes. This one-pot dick reaction using a copper flow reactor eliminated both the handling of organic azides and the need for additional copper catalyst and enabled the preparation of numerous triazoles in a continuous-flow process. 

FIGURE 3.18 Temperature dependence of the CH3OH yield in a copper flow reactor at [O2]o = 3%, t, = 1.8s, and P = ( ) 200 and ( ) 300 atm. Based on the data from [51], (For interpretation of the references to colour in this figure legend, the reader is referred to the online version of this book.)... 

Bogdan A.R., James K. Synthesis of 5-iodo-l,2,3-triazole-containing macrocycles using copper flow reactor technology. Org. Lett. 2011 13(15) 4060 063. 

Dibromotetrafluoropropene passed over copper yields tetrafluoroallene (39%) and perfluoropropyne (11%) [23] Similarly, perfluorocyclobutene in a nickel flow reactor in contact with cesium fluoride at temperatures over 450 °C yields perfluorobutyne (40%) [24] At 590-600 °C, the yield is greater than 90% [25]... 

In the present work CWPO of dyehouse effluent was carried out in a batch reactor with IL capacity and in a pilot plant scale continuous flow reactor with 5ra /day treatment capacity. Cu/Al203 and Copper plate were used as the catalysts. 

Figure 8.13. Rate of methanol synthesis of a Cu/Zn0/Al203 catalyst in a plug flow reactor as a function of time on stream. The catalyst was operated at 494 K and 63 bar in a gas steam of 5 % CO, 5 % COj, 88% H2, and 2% N2. Note the steady decrease in reactivity, which is ascribed to sintering ofthe copper particles. The CO2 was removed from the reactants for 4 h after 168 h. After reintroduction the catalyst displays a restored...

Cunningham et al (63) have studied the rate of hydrogenation of ethylene at 1 atm on a copper-magnesium oxide catalyst. They used flow reactors to study the reaction kinetics over both finely divided catalyst particles and spherical... 

Airco A modification of the Deacon process for oxidizing hydrogen chloride to chlorine. The copper catalyst is modified with lanthanides and used in a reversing flow reactor without the need for external heat. Developed by the Air Reduction Company from the late 1930s. U.S. Patents 2,204,172 2,312,952 2,271,056 2,447,834. 

The air oxidation of 2-methylpropene to methacrolein was investigated at atmospheric pressure and temperatures ranging between 200° and 460°C. over pumice-supported copper oxide catalyst in the presence of selenium dioxide in an integral isothermal flow reactor. The reaction products were analyzed quantitatively by gas chromatography, and the effects of several process variables on conversion and yield were determined. The experimental results are explained by the electron theory of catalysis on semiconductors, and a reaction mechanism is proposed. It is postulated that while at low selenium-copper ratios, the rate-determining step in the oxidation of 2-methylpropene to methacrolein is a p-type, it is n-type at higher ratios. 

In another example employing multiple supported catalysts and reagents, Smith et al. (2007a) presented a modular flow reactor in which 14 1,4-disubstituted-l,2,3-triazoles were synthesized. Coupling an immobilized copper(I) iodide species 148 with two scavenger modules (immobilized thiourea 149 and phosphane resin 150), the authors reported the [3 + 2] cycloaddition of an array of azides and terminal acetylene (30 pi min x) to afford the desired 1,4-disubstituted 1,2,3-triazoles (Scheme 40) in moderate to excellent yield (70-93%). 

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). 

In this chapter the performance of plalinum/base metal fuel additive-filter systems is discussed with studies on a pilot engine as a basis. It will be compared to the performance of cerium, iron, and copper base metal additives, the latter two also in combination with platinum. The background of the difference in performance of the platinum/base metal combinations is discussed with results from flow-reactor experiments as a basis. 

The cyclopropanation of gaseous alkenes, butadiene, and allene (see Section 1.2.1.2.4.2.6.3.3., Table 11, entry 1) by diazoacetic esters can be achieved by passing a vapor-gas mixture of the alkene and the diazo compound at atmospheric pressure through a tubular continuous flow reactor which contains a copper catalyst (ca. 10%) deposited on pumice. In this manner, alkyl cyclopropanecarboxylates were obtained in yields of up to 50% with cop-per(II) sulfate (typical reaction temperature 65-110"C, contact time 3.6 s) or copper(II) oxide (85-200°C, 5s) as catalysts. 

In flow-reactor experiments, the effect of NO in the gas phase and a supported platinum catalyst mixed with the soot is twice as large for cerium when compared to that of copper, iron, and Printex-U. All other conditions are similar and, therefore, it is concluded that cerium catalyses the oxidation of soot with NO2. Because there is... 

Cerium-, copper-cerium coexchanged ZSM-5, copper-MCM-22, copper- and cerium-EMT type zeolite, copper-FAU type zeolite and copper-Beta exhibit an activity of the same order as that of copper-ZSM-5 in NOx reduction under simulated Diesel exhaust conditions. Propene was used as the reducing agent. The catalysts were used in a powder form and their activities tested in a fixed-bed flow reactor at a space velocity of 50 000 H . Copper-SAPO-34 and cerium- and gallium-EMT type zeolite have a moderate activity under the same conditions. The presence of water vapor inhibits the activity of EMT-zeolites. When an ageing procedure is carried out on copper-EMT type zeolite, dealumination occurs. The increase of the Si/Al ratio of the zeolite does not limit the dealumination process. The exchange of the zeolite with lanthanum prevents the zeolite from dealumination but leads to a loss of the catalytic activity. 

Numerous studies have shown that low hydrogen overpotential electrically conducting catalysts (e.g., Raney nickel, platinum and palladium on carbon powder, and Devarda copper) can be used to electrocatalyticaUy hydrogenate a variety of organic compounds including benzene and multiring aromatic compounds, phenol, ketones, nitro compounds, dinitriles, and glucose [45, 46, 54, 55, 67-71]. These reactions have been carried out in both batch and semicontinuous flow reactors in most cases, the reaction products were similar to those obtained from a traditional chemical catalytic scheme at elevated temperatures and pressures. 

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