Carbon monoxide mixing ratios

Reichle Jr H.G, V.S. Connors, J.A. Holland, W.D. Hypes, HA. Wallio, J.C. Casas, B.B. Gormsen, M.S. Saylor and W.D. Hesketh (1986) Middle and upper tropospheric carbon monoxide mixing ratios as measured by a satellite-bome remote sensor during November 1981. Journal of Geophysical Research 91 10865-10887... 

Figure 5.20. Distribution of the zonal mean carbon monoxide mixing ratio (expressed in ppmv) in the stratosphere and mesosphere represented as a function of latitude and atmospheric pressure (or approximate altitude), as measured on 7 August 2001 by the Sub-Millimetre Radiometer on board the Odin satellite. Note the downward transport of CO at high latitudes in the winter hemisphere. From Duprey et at, 2004.

Fig. 4-8. Meridonal cross section of carbon monoxide mixing ratios over the Atlantic Ocean. Contours give CO mixing ratios in units of ppmv. [Adapted from Seiler (1974) and Seiler and Schmidt (1974a).]...

Seiler, W., and C. Junge (1969). Decrease of carbon monoxide mixing ratio above the polar tropopause. Tellus 21, 447-449. 

Measurement of Air Pollution from Satellites Carbon Monoxide Mixing Ratios in Middle Troposphere during April and October 1994... 

Fresh feed that has the proper hydrogen carbon monoxide ratio (i.e., slightly above the 3 1 minimum stoichiometric ratio) is mixed with recycle gas and sent through a heat exchanger and into the first catalyst bed, Stage I. The space velocity in Stage I is controlled so that all of the carbon monoxide fed to it is completely converted. The inlet gases are... 

Carbon Monoxide. Methods for determining carbon monoxide include detection by conversion to mercury vapor, gas filter correlation spectrometry, TDLAS, and grab sampling followed by gas chromatograph (GC) analysis. The quantitative liberation of mercury vapor from mercury oxide by CO has been used to measure CO (73). The mercury vapor concentration is then measured by flameless atomic absorption spectrometry. A detection limit of 0.1 ppbv was reported for a 30-s response time. Accuracy was reported to be 3% at tropospheric mixing ratios. A commercial instrument providing similar performance is available. 

Carbon monoxide volume mixing ratio (ppm) qC02... 

Add a small amount of sodium dithionite to each of die solutions A, B, and C, and also to 10 ml of 0.1% ammonia solution, and mix well. Place matched 1-cm cells containing the ammonia solution into die sample and reference beams of a specftophotometer which has been set to record between the wavelengdis 500 and 650 nm, in the superimposed, repeat-scan mode on a range of 0 to 2 absorbance units. Record the baseline for the determination. Then record the absorbance spectra for solutions A, B, and C. Wash out the sample cell thoroughly between the recordings and wash the cell with a little of the solution whose absorbance is about to be recorded. If the blood sample was from a person who died from inhalation of carbon monoxide, a set of spectra as shown in Fig. 3 should be obtained. Measure the absorbances of each solution at 540 nm and 579 nm, and calculate the ratio of absorbance at 540 to that at 579 nm for each of the solutions A, B,and C. 

At a one-to-one pressure ratio of ethylene to<arbon monoxide of around 1000 psig, the major product is succinate this is in contrast to the production of acrylic acid, where succinic add was not isolated. If the olefin is left out of the reaction mix, then oxalates are produced and this is a practical route to oxalates, particularly at carbon monoxide pressures above 500 psig. The formation of water is a severe problem for the stability and activity of the catalytic system, since in the presence of water there is a parallel reaction which produces considerable amounts of carbon dioxide. 

Carbon monoxide (CO) strongly influences the concentration of the radical OH in the tropical atmosphere. CO oxidation can lead to either production or destruction of ozone, depending on the NOx mixing ratio. Tropical soils are either a sink or a weak source of CO, where photochemical oxidation of methane and other hydrocarbons and biomass burning emissions are the predominant CO sources. 

It is interesting to note that the sources of both methane and carbon monoxide are mostly continental rather than oceanic. Because most of the world s land mass is in the northern hemisphere, the largest sources of both compounds are there. One might expect, therefore, to find an inter-hemispheric asymmetry for both methane and carbon monoxide. However, as can be seen in Figure 6, whereas considerably more carbon monoxide is found in the northern hemisphere, methane has a nearly constant mixing ratio of 1.65 ppmv with only a slight change in abundance across the ITCZ near the equator. 

A mixture of carbon monoxide, hydrogen, and carbon dioxide is produced by steam reforming, a process in which natural gas and steam are mixed and reacted in a reformer operated at 1.6 MPa. Natural gas may be assumed to consist entirely of methane (CH4), although other compounds may be present in small concentrations. In the present process, steam and natural gas are fed to the reformer in a ratio of 3.0 moles of steam per mole of methane. The reformer consists of an arrangement of vertical tubes filled with nickel-impregnated ceramic catalyst. Rows of these tubes are located inside an insulated firebox, where they are heated by the combustion of natural gas. 

In operation, the gases enter at diametrically opposite sides of the cylindrical combustion chamber. It is here that much carbonyl fluoride is formed and much heat is liberated. If flow rates are too high, the heat of the reaction may ignite copper in contact with fluorine. The capacity of the apparatus to produce trifluoromethyl hypo-fluorite appears to be limited by the rate of removal of heat from this reactor. A mixing chamber made from copper, nickel. Monel metal, or other fluorine-resistant metal should be satisfactory, provided that adequate provision is made for removal of heat. Suitable rates of flow for the apparatus described are fluorine, about 5 l./hour carbon monoxide, about 2 to 2.3 l./hour. The limiting rates have not been established. It is important that the ratio by volume of fluorine to carbon monoxide be somewhat more than 2 1. 

Carbon monoxide (CO), a toxic gas, is produced during combustion, both in wildfires and in fuel-burning devices CO also can be produced and consumed by bacterial activity. The presence of CO may indirectly increase the atmospheric mixing ratios of other gases by competing for oxidant species (such as the hydroxyl radical, OH-), thereby decreasing the oxidation rates of the other gases. This competition for oxidant species is believed to be one reason for the current increase in atmospheric methane, whose major atmospheric sink is reaction with the hydroxyl radical. 

References may be found in the literature to attempts made for the purpose of reacting ethylene in a variety of other ways to obtain useful products. Condensation and oxidation products are claimed to lie formed when ethylene mixed with steam, ammonia, or hydrogen sulfide is passed over catalysts at high temperatures.811 Unsuccessful attempts have been made to obtain acetone by reacting ethylene with hydrogen and carbon monoxide in a molal ratio of 1 2.5 1, respectively, at 300° C. and 150 to 250 atmospheres pressure in the presence of a basic zinc chromate catalyst. In this case methanol was formed, a portion of the ethylene polymerized, and a portion was reduced to ethane.888 No acetone was formed. 

Volume mixing ratio (ppm) of carbone monoxide in the troposphere (Seiler, 1974). (By courtesy of Tetha)... 

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