Copper flow system

Besides the synthesis of various triazoles, the synthetic potential of the copper flow system was further demonstrated by the catalytic decarboxylation of the propargyhc add 11 (Scheme 4, Reaction 2) and the C—O coupling in the synthesis of benzopyranone 14 (Scheme 4, Reaction 3) (2010SL2009). 

Figure 7. Removal of TOC( ) and color(A) during catalytic wet oxidation of a real dyehouse effluent with copper plate in the continuous flow system.

Figure 4.14 — (A) Flow injection system for the preconcentration and determination of copper P peristaltic pumps A 0.5 M HNOj B sample q = 2.5 mL/min) C water (jq = 0.5 mL/min) E 1 M NaNOj/O.l M NaAcO, pH 5.4 q = 0.5 mL/min F 1 M NaAcO/2 x 10 M Cu pH 5.0 (9 = 1.0 mL/min) 3-5 valves ISE copper ion-selective electrode W waste I and II 2 and 3 mL of chelating ion exchanger for purification III 100 fil of chelating ion exchanger for metal ion preconcentration. (B) Scheme of the flow system for the determination of halides A 4 M HAcO/1 M NaCl/0.57 ppm F B 1 M NaOH/0.5 M NaCl C, mixing coil (1 m x 0.5 mm ID PTFE tube) Cj stainless-steel tube (5 cm x 0.5 mm ID) ISE ion-selective electrode R recorder. (Reproduced from [128] and [129] with permission of Elsevier Science Publishers and the Royal Society of Chemistry, respectively).

Fiq. 7. Reaction rates on plane faces of a copper crystal at 400° with 5% oxygen (continuous-flow system). 

Another important precaution is with the tubing where the gas passes (preferably copper, glass, etc.) and, in a flow system, also with tubing through which deoxygenated solution passes. All flexible plastics are... 

In some flow systems contamination of solutions with copper on lead ions may be removed through a trap containing aluminum filings which otherwise might cause corrosion and a typical trap is depicted in Figure 1.51. 

Figure 22-3 shows, for both reactions, the relation between temperature and or vapor pressure p. The lines represent extrapolation to room temperature of data obtained in the temperature range 360 to 665°C for copper and 210 to 605 C for tin. The reaction rates at room temperature are too slow to attain equilibrium, especially in a flowing system. Greater selectivity of reaction exists at low temperatures than at high temperatures. However, since it is desired to vaporize the tin(II) chloride formed. 

Using stoicheiometric feeds of CO, HCI, and Oj in a flow system at 393 C and atmospheric pressure, a selectivity to phosgene of 57.2% was obtained with a conversion of CO corresponding to 42%. The only significant by-product in this reaction is carbon dioxide which is formed principally from the reaction of the product phosgene with the copper catalyst in its oxychloride state. The overall catalytic scheme is illustrated in Fig. 5.5. 

Carbon bromide fluoride is formed in a flow system with a yieid of 30% when a mixture of dinitrogen (saturated with dibromine), molecular fluorine, and carbon monoxide are passed simultaneously through a copper tube [1751]. No further details of this preparation are available, but if it is probably consistent with the stoicheiometry shown in Equation (16.7). 

The flow system is designed to permit successive injections of the sample, each one accompanied by the injection of a different standard solution. Merging of the established zones permits the efficient implementation of the standard addition method involving a fixed sample dilution. The approach was initially exploited in the routine analysis of copper/ nickel alloys by ICP-OES [22], the spectral interferences being minimised by applying the generalised standard addition method [23]. This innovation however required the preparation of a large set of standard solutions. 

Copper Bovine liver, river water, lake water MIBK UV-Vis 5.0 pgL-1 Flow system with gaseous carrier streams micro-batch chamber for chemical reactions, extraction and phase separation l-(2 -pyridylazo) naphthol in the organic phase [460]... 

J.A. Gomes-Neto, A.P. Oliveira, G.P.G. Freshi, C.S. Dakuzaku, M. Moraes, Minimization of lead and copper interferences on spectrophotometric determination of cadmium using electrolytic deposition and ion-exchange in multi-commutation flow system, Talanta 53 (2000) 497. 

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