Carbon monoxide air pollutants

The Glean Air Act of 1963 and amendments of 1970 and 1990 mandate monitoring of six criteria air pollutants—carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone, particulate matter, and lead— with the aim of reducing release into the... 

The time-series analysis results of Merz et were expressed in first-order empirical formulas for the most part. Forecasting expressions were developed for total oxidant, carbon monoxide, nitric oxide, and hydrocarbon. Fitting correlation coefficients varied from 0.547 to 0.659. As might be expected, the best results were obtained for the primary pollutants carbon monoxide and nitric oxide, and the lowest correlation was for oxidant. This model relates one pollutant to another, but does not relate emission to air quality. For primary pollutants, the model expresses the concentrations as a function of time. 

Exposure to air pollutants can have adverse effects on human health. Exposure to one such pollutant, carbon monoxide, can result in which of the following conditions ... 

Air quality standards. The Environmental Protection Agency EPA has established health-based National Ambient Air Quality Standards (NAAQS) for six pollutants carbon monoxide, ozone, nitrogen oxide, sulfur dioxide, particulate matter, and lead. The current NAAQS are presented in Table 7.9. (US EPA, 1993). 

The respiratory tract includes the air passages through the nose and mouth that connect to the tubing (bronchi) that lead to the lungs. Gases such as oxygen and carbon dioxide, and the environmentally important pollutants carbon monoxide, nitrogen oxides, sulfur dioxide and... 

Introducing the major air pollutants The major chemicals that pollute the air are carbon monoxide, CO carbon dioxide, CO2 sulfur dioxide, SO2 nitrogen monoxide, NO nitrogen dioxide, NO2 hydrocarbons and suspended particles. 

At local and urban levels, it is essentially a question of vicinity pollution. Several air pollutants are concerned sulphur dioxide, SO2 (primary pollutant) nitrogen oxides NO (primary or secondary pollutants) particulate matter PM (primary and secondary pollutants) carbon monoxide, CO, (primary pollutant) (volatile) organic compounds, HC (or VOCs) (primary and secondary pollutants), and photochemical oxidants, O3, PAN (secondary pollutants). Organic compounds account for a wide range of hydrocarbons and are found in solid, liquid, and gas forms. 

Characterize the chemical aspects of photosmog. Write the cycles of chemical reactions in polluted urban air using carbon monoxide and methane as theexample species. 

Three-Way Conversion (TWC) Catalyst. The dual-bed method requires net fuel-rich operation of the engine and therefore lower fuel economy. Interest has heightened recently in a technique to control all three pollutants—carbon monoxide, hydrocarbon, and nitrogen oxides— by maintaining the air/fuel (A/F) at near-stoichiometric ratios and by converting all pollutants over a single catalyst. A sensor is used to control the partial pressure of oxygen in the exhaust stream by feedback to a carburetion or fuel injection system (13). The increased cost of the sensor-carburetor system will be compensated for by better fuel economy,... 

The following graph shows the concentration of an atmospheric pollutant, carbon monoxide, for the period 1997 2006. As shown by this graph, carbon monoxide levels have decreased in the atmosphere because of mandatory reductions legislated by the Clean Air Act. 

Since the internal combustion engine is the primary source of localized pollutant carbon monoxide emissions, control measures have been concentrated on automobiles and have been very successful in reducing carbon monoxide emissions. Carbon monoxide emissions may be lowered by employing a leaner air-fuel mixture, that is, one in which the mass ratio of air to fuel is relatively high. At air-fuel (mass mass) ratios exceeding approximately 16 1, an internal combustion engine emits virtually no carbon monoxide. Modern automobiles use catalytic exhaust reactors and precise computerized control of engine operation to cut down on carbon monoxide emissions. 

Suppose that polluted air has carbon monoxide (CO) levels of 15.0 ppm. An average human inhales about 0.50 L of air per breath and takes about 20 breaths per minute. How many milligrams of carbon monoxide does the average person inhale in an 8-hour period at this level of carbon monoxide pollution Assume that the carbon monoxide has a density of 1.2 g/L. (Hint 15.0 ppm CO means 15.0 L CO per 10 L air.)... 

Natural gas is attractive as a fuel ia many appHcatioas because of its relatively clean burning characteristics and low air pollution (qv) potential compared to other fossil fuels. Combustion of natural gas iavolves mixing with air or oxygen and igniting the mixture. The overall combustion process does not iavolve particulate combustion or the vaporization of Hquid droplets. With proper burner design and operation, the combustion of natural gas is essentially complete. No unbumed hydrocarbon or carbon monoxide is present ia the products of combustioa. 

National Ambient Air Quality Standards. Under the Clean Air Act, six criterion pollutants, ie, pollutants of special concern, have been estabhshed by the EPA sulfur oxides (SO ), particulates, carbon monoxide (CO), nitrogen oxides (NO ), o2one (photochemical oxidants), and lead. National Ambient Air QuaUty Standards (NAAQS) were developed by EPA based on threshold levels of air pollution below which no adverse effects could be experienced on human health or the environment. 

Air pollution (qv) problems are characteri2ed by their scale and the types of pollutants involved. Pollutants are classified as being either primary, that is emitted direcdy, or secondary, ie, formed in the atmosphere through chemical or physical processes. Examples of primary pollutants are carbon monoxide [630-08-0] (qv), CO, lead [7439-92-1] (qv), Pb, chlorofluorocarbons, and many toxic compounds. Notable secondary pollutants include o2one [10028-15-6] (qv), O, which is formed in the troposphere by reactions of nitrogen oxides (NO ) and reactive organic gases (ROG), and sulfuric and nitric acids. 

Carbon monoxide was discovered in 1776 by heating a mixture of charcoal and 2inc oxide. It provided a source of heat to industry and homes as a component of town gas and was used as a primary raw material in German synthetic fuel manufacture during World War II its compounds with transition metals have been studied extensively (see Carbonyls). Most recently, carbon monoxide emission from vehicle exhausts has been recognized as a primary source of air pollution (qv). 

ERA promulgated the basic set of current ambient air-quality standards in April 1971. The specific regulated pollutants were particulates, sulfur dioxide, photochemical oxidants, hydrocarbons, carbon monoxide, and nitrogen oxides. In 1978, lead was added. Table 25-1 enumerates the present standards. 

Human-made sources cover a wide spectrum of chemical and physical activities and are the major contributors to urban air pollution. Air pollutants in the United States pour out from over 10 million vehicles, the refuse of over 250 million people, the generation of billions of kilowatts of electricity, and the production of innumerable products demanded by eveiyday living. Hundreds of millions of tons of air pollutants are generated annu ly in the United States alone. The five main classes of pollutants are particulates, sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. Total emissions in the United States are summarized by source categoiy for the year 1993 in Table 25-10. 

---