Carbon monoxide deleterious effect

Horvath, S.M., T.E.Dahms, and I.F.O=Hanlon. 1971. Carbon monoxide and human vigilance a deleterious effect of present urban concentrations. Arch. Environ. Health 23(5) 343-347. Horvath, S.M., P.B.Raven, T.E.Dahms, and D.I.Gray. 1975. Maximal aerobic capacity at different levels of carboxyhemoglobin. J. Appl. Physiol. 38(2) 300-303. 

The effect of trace contaminants on the reaction has been investigated carefully. All uncondensed effiuent gases were recycled to the reactor, except for the amounts present in the streams taken off for analysis or flashed upon depressuring of the organic phase. Aqueous phase from the separator containing the water soluble by-products has been used as the water feed to the reactor. Hydrogen chloride containing chlorinated hydrocarbons and acetylene was used in all operations. In addition, certain possible impurities were tested for their effect on the kinetics and selectivity of the process. Paraffins, carbon monoxide, sulfide, carbon dioxide, alkali, and alkaline earth metals were found to be chemically inert. Olefins, diolefins and acetylenic compounds are chlorinated to the expected products. No deleterious effects of by-product recycle were observed even when some of the main by-products were added extraneously. 

The objective of this investigation was to examine the effect of water vapor on the reduction of sulfur dioxide with carbon monoxide on an iron-alumina bifunctional catalyst and to devise double-catalyst beds to cope with the deleterious effect of water. The catalyst temperature of the first bed in this double-bed system was varied to adjust the ratio of reactants entering the second bed in order to maximize the removal of sulfurous gases. 

The apparatus and the general experimental technique employed were the same as those described earlier 8). Experiments were conducted by the static method in the gas phase. The products of the reaction were released from the bomb at the reaction temperature. Commercial ethylene (99.2% pure), carbon monoxide (prepared in the laboratory by the action of formic acid on concentrated sulfuric acid), distilled water, A.E.. grade n-propyl, and n-butyl alcohols were the reactants used. The ethylene gas contained a small amount of sulfur, which, however, was found to have no deleterious effect on the synthesis. 

If we consider the reactions of metalloenzymes, it is not difficult to identify organometallic-type chemistry. Many of these reactions have been known for some time. For example, the well-known deleterious effect that carbon monoxide has on the reactivity of a variety of metalloproteins. The effect is a consequence of carbon monoxide binding to a metal site in the enzyme. 

Carbon monoxide purity requirements vary considerably depending on end products. By-products formed during the production of phosgene can have a deleterious effect on downstream products formed by the phosgenation reaction. In general, the requirements for polycarbonates are more stringent then for isocyanates. The recommended CO feedstock specifications for each downstream product are given in the section for each product. 

The presence of trace amounts of hydrogen, oxygen, and carbon monoxide can have deleterious effects in certain processes using hydrocarbon products as feed stock. This test method is suitable for setting specifications, for use as an internal quality control tool and for use in development or research work. 

Impurities and Poisons The presence of any impurities or catalyst poisons in the reacting flow can have a highly deleterious effect on performance. Some impurities such as carbon monoxide and sulfur dioxide can reduce performance dramatically for certain fuel cells, even in levels as low as parts per million (ppm) or parts per billion (ppb). Each catalyst and fuel cell has different poisons. For instance, carbon monoxide is a serious poison for low-temperature PEFCs but can be oxidized as a fuel in high-temperature MCFCs and SOFCs. 

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