Carbon monoxide, atmospheric residual atmosphere

The processor was operated at atmospheric pressure and at 117—130 °C or 200 °C. A methanol-water mixture (1 1.5 molar ratio) was fed at 0.1 cm /h using a syringe pump. The reactors loaded with powder and pellets had comparable results, but the researchers preferred the powder packed bed form for its smaller volume and mass. The best hydrogen production was obtained at low temperatures, providing, on a dry gas basis, 70% hydrogen, 0.5% carbon monoxide, and residual carbon dioxide. Methanol conversion or thermal efficiency was not reported. 

The compound Ru3H(CO)9(C2-t-Bu) (1.243 g, 1.950 mmol) is treated with alcoholic potassium hydroxide (17.5mL of 0.128 M, 2.24 mmol) followed by mercury(II) iodide (0.444 g, 0.978 mmol) as outlined in the procedure in Section (B.l). The resulting solution is allowed to stir under a carbon monoxide atmosphere until a bright yellow precipitate forms. The reaction time is typically 30 to 45 min. Upon precipitation, the reaction mixture is evaporated to dryness under reduced pressure. The resulting residue is washed first with 50 mL of absolute ethanol and then with 25 mL of dichloromethane. The remaining yellow residue is recrystallized from hot THF. Yield 1.16-1.20 [81-84% yield based on Ru3H(CO)9(C2-t-Bu)]. 

The Step 5 product dissolved in 80 ml DMF was initially treated with 25 ml methyl alcohol, 1.5 ml triethylamine, 1.5 ml Et3N and diphenyl-l-pyrenylphosphine (0.212 mmol). The mixture was subsequently treated with Pd(OAc)2 (0.247 mmol), then heated 90 minutes at 95°C, and saturated with carbon monoxide. The mixture was heated for additional 30 minutes under a carbon monoxide atmosphere, then quenched with 100 ml ice. The mixture was extracted twice with CH2C12, dried, and concentrated. The residue was purified by chromatography with silica gel using EtOAc/hexanes, 1 4, and the product isolated in 99% yield as a crystalline solid. 

Step 16. The combustion products leave the furnace at 250 C and flow through the chlorine vapor heat exchanger (this stream is the flue gas referred to in Step 3) and then to a flare, where any carbon monoxide and residual hydrocarbons in the gas are burned and the products released to the atmosphere. The flare is a safety precaution if the furnace operates as intended, the CO and hydrocarbon content of the flue gas should be negligible. 

To a solution of 4-nitrobenzaldehyde (151 mg, 1.0 mmol) and zinc(Il) chloride (0.15 mL, 1 M in dichloromethane, 0.15 mmol) in dichloromethane (5 mL) is added a freshly-prepared solution of ri -allyl-Fp (5 mL, 0.5 M, 2.5 mmol) under an argon atmosphere. The reaction is stirred at room temperature for 14 h and then added dropwise over a 30-min period to a solution of ceric ammonium nitrate (4.1 g, 7.5 mmol) in methanol (20 mL) at -78 °C under a carbon monoxide atmosphere. After the solution is stirred at -78 °C for an additional 30 min, the solvent is warmed to room temperature and allowed to stir for an additional 30 min, and then it is evaporated in vacuo. The residue is triturated several times with small portions of dichloromethane until the washings are colorless. After removal of the solvent, the residue is purified by column chromatography (Si02, dichloromethane and then 2% acetone in dichloromethane). Purification by a second chromatography affords the tetrahydrofuran ester (3.1 1 mixture of diastereoisomers) as a yellow oil 178 mg (71%). ... 

A major source of particulate matter, carbon monoxide, and hydrocarbons is open burning of agricultural residue. Over 2.5 million metric tons of particulate matter per year are added to the atmosphere over the United States from burning rice, grass straw and stubble, wheat straw and stubble. 

Ruthenium Dicarbonyl, Ru(CO)a.—Ruthenium, like iron, yields a carbonyl derivative. It is obtained as an orange-yellow deposit upon subjecting ruthenium black to the action of carbon monoxide at 300° C. under a pressure of 400 atmospheres. The product is extracted from the residue by solution in alcohol. It is insoluble in benzene and in hydrochloric acid, but soluble in nitric acid and in bromine, gas being evolved. When heated, a mirror of metallic ruthenium is produced.5 In contradistinction to the other carbonyls of this group of metals ruthenium dicarbonyl is not volatile. 

Le Van et al. [117] concluded, from X-ray studies of the decomposition of nickel malonate in an inert atmosphere, that finely divided nickel was the first formed residual product and this was subsequently carbonized by carbon monoxide. The shapes of the ur-time curves for decomposition in vacuum and in the presence of water vapour [116] or oxygen [118] were closely comparable, although the values of E, (and the reaction products) were significantly changed (179, 137 and 157 kJ mol , respectively for the reactions mentioned). 

The reaction is carried out in a Schlenk tube, Fig. 1. Acetone (10 mL) is cooled in an ice bath and saturated with carbon monoxide by passing in a brisk stream of the gas for 10 minutes. Potassium hydrotris(pyrazolato)borate (252 mg, 1.0 mmole) and copper(I) chloride (99 mg, 1 mmole) are added to the acetone, and the mixture is stirred for 30 minutes while continuing to pass a slow stream of carbon monoxide. At the end of this period, the white suspension is filtered, using the Schlenk-type apparatus illustrated, Fig. 2, keeping the whole under an atmosphere of CO. The clear colorless filtrate is evaporated to dryness, and the cream-colored residue is extracted with 10 mL light petroleum (boiling range 40-60°, saturated with CO) and filtered. Evaporation of the solvent from the filtrate affords a white powder of Cu(CO)[(pz)3BH] (156 mg, 51%). 

Pyrolysis of cellulose at 170° in an atmosphere of nitrogen or oxygen has been studied. At this temperature, heating under nitrogen had little effect, but, under oxygen, there was a primary oxidation effect in the amorphous regions. The rates of production of carbon dioxide, carbon monoxide, and water, and the formation of carboxyl and carbonyl groups in the residue, were measured. 

In general high pressure and temperature are required for these reactions to occur. However there are significant examples of reactions catalysed at atmospheric pressure, in part icular for the synthesis of isocyanates (4.2.5.). In the majority of cases the most important steps of these reactions are supposed to be the deoxygenation of the nitro function by carbon monoxide iving a nitrene residue bound to the metal centre, followed by insertion of carbon monoxide into the metal-nitrene bond. This is a likely hyphotesis since nitrene complexes can be obtained by stoichiometric reactions of nitro compounds with metal carbonyls. Conversion of the imido metal complex to the observed... 

The apparatus for the preparation of rhenium(VII) oxide (synthesis 50) is modified by interposing a short (2- to 3-mm.) section of 1-mm. capillary tubing between the reaction tube and the remainder of the apparatus as depicted in Fig. 39. One-tenth to one gram of rhenium metal is converted into rhenium(VII) oxide, which is purified by sublimation. Any nonvolatile residue remaining in the tip of the reaction tube is sealed off and detached. The reaction tube is bent from a horizontal to a vertical position as indicated in Fig. 38. The system is evacuated and filled with carbon monoxide to a pressure of one atmosphere. The tube containing the rhenium (VI I) oxide is slowly heated to 175° by means of a glycerol bath and is maintained at that temperature until the oxide is blue. The temperature is then raised slowly to 225°, and, after the preparation has turned red, is increased to 280°. The... 

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