Carbonaceous material aerosols

Smoke An aerosol of carbon or soot particles less than 0.1pm in diameter that results from the incomplete combustion of carbonaceous materials such as coal or oil. Smoke generally contains droplets as well as dry particles. 

Appel, B.R. Colodny, P. Wesolowski, J.J. "Analysis of carbonaceous materials in Southern California aerosols". Environ. Sci. Technol.. 1976, W, 359-363. 

Ambient aerosols, particularly those with diameters less than 3pm, are a serious pollution problem. Carbonaceous material is a major component of the fine particle concentration (10 and has undergone extensive study in the past few years (, ) in large part because of the concern that these particles play an Important role in urban haze and community health. 

Carbonaceous Materials in Southern California Atmospheric Aerosols, Environ. Sci. Technol. 1976, 359. 

Appel, B. R., S. M. Wall, and R. L. Knights, "Characterization of Carbonaceous Materials in Atmospheric Aerosols by High Resolution Mass Spectrometric Thermal Analysis, Adv. Environ. Sci. Technol., 10, 353-365 (1980). 

Smoke A mixture of gases, vapors, and aerosols formed from the incomplete combustion of carbonaceous materials. 

Atmospheric particles in the troposphere are composed of a complex mixture of highly water-soluble inorganic salts, insoluble mineral dust, and carbonaceous material (which includes organic compounds plus elemental carbon) (Jacobson et al., 2000). Studies in which the chemical composition has been determined as a function of particle size demonstrate a correlation between the chemical composition and the size mode of atmospheric aerosols (Meszaros et al., 1997 Krivacsy and Molnar, 1998 Alves et al.,2000 Maenhaut et al.,2002 Smolik et al., 2003 Samara andVoutsa, 2005). 

Some studies have also shown that carbonaceous material can be responsible for about 1.2-31% of the coarse fraction mass concentration of the atmospheric aerosol (Maenhaut et al., 2002 Hueglin et al., 2005). Nevertheless, the highest concentrations (17-48%) of organic matter and elemental carbon are found predominantly... 

Carbonaceous materials (predominantly found in the fine size mode) and sometimes the dominant fraction of the total fine particle mass (Andrews et al., 2000 Putaud et al., 2004) have been usually classified as organic carbon (OC), elemental carbon (EC), and inorganic carbon (IC). The latter fraction typically consists of mineral carbonates derived almost exclusively from soil dust (Seinfeld and Pankow, 2003). Since mineral carbonates are commonly discarded from chemical aerosol mass closures, data on total carbon (TC) content of air particulate matter at sites representing different pollution levels refers only to the sum of OC and EC... 

Particulate emissions are by-products of fuel combustion, industrial processes, and motor vehicles and are believed to have a significant potential for causing adverse health effects. Carbonaceous material present in atmospheric aerosols is a combination of elemental carbon and organic and inorganic compounds. Particulate matter may also consist of fly ash, minerals, or road dust and contain traces of a number of heavy metals. Population-based studies have consistently found that the association between adverse respiratory effects and particulate concentrations occurs in a number of regions throughout the United States. This association is strongest for PM]o and PM2.5 indices (particulate matter less than 10 and 2.5 pm in diameter, respectively). The observed adverse effects include increases in total mortality, mortality due to respiratory and cardiovascular causes, chronic bronchitis, and hospital visits and admissions for asthma. Elderly or unhealthy individuals and infants appear to comprise subpopulations that are most sensitive to the adverse health effects of PM. 

We can see that particulates originate from a wide variety of sources and processes, ranging from simple grinding of bulk matter to complicated chemical and biochemical syntheses. For the most part, aerosols consist of carbonaceous material, metal oxides... 

Elemental balances for atmospheric particles indicate that trace metals comprise only a small fraction of the total aerosol mass. Even in a highly industrialized city such as Linz (Austria), the relative contribution of trace metal compounds (Cd, Cr, Cu, Mn, V, Zn, and Pb compounds) to the total suspended particles (TSP) was found to be about 1%, while Ee-compounds comprised 1-8% of the TSP mass (Puxbaum etal. 1985). The major part of the TSP is formed by electrolytes (Na, K" ", NH, Cl , NOj, SO ) (25-35%), carbonaceous material (8-11%), and mineralic components (Ca, Mg, Si, Al compounds) (16-18%). Similar results were found for aerosols collected at a background site in the South African savanna (Puxbaum et al. 2000). 

The polar aerosol contains carbonaceous material from midlatitude pollution sources, sulfate, seasalt from the surrounding ocean, and mineral dust from arid regions of the corresponding hemisphere. Aerosol PM10 concentrations in the polar regions are less than 5 pg m-3 with sulfate representing roughly 40% of the mass. 

In Table 15.5 this procedure was followed with the exception of Na, which was assumed to be in the form of an ionic solid. Mg was present at negligible levels, and thus its chemical form is unimportant to the aerosol mass balance. To account for hydrogen and oxygen present in the hydrocarbons, the mass of organic carbonaceous material was taken to be 1.2 times the organic carbon mass measured (Countess et al. 1980). The ionic material was assumed to be distributed as follows ... 

Carbon dioxide occurs in the atmosphere at 0.033%. It is produced by burning carbonaceous materials. It is used in the carbon-ation of beverages in fire extinguishers, in the manufacture of carbonates, as dry ice for refrigeration, and as a propellant for aerosols. 

Appel, B. R. 1981. Characterization of carbonaceous materials in atmospheric aerosols by high-resolution mass spectrometric thermal analysis. In G. M. Hidy, ed.. The aerosol characterization experiment. Wiley-Interscience, New York. 

Smoke smok [ME, fr. OE smoca akin to OE smeocan to emit smoke, MHGr smouch smoke, and prob. to Gk smychein to smolder] (before 12c) n. Carbon or soot particles less than 0.1 pm in size which result from the incomplete combustion of carbonaceous materials such as coal or oil. Air suspension (aerosol) particles, often originating from combustion or sublimation. 

The quanitity of the raw material necessary to produce a reliable estimate of any element will depend on the selected detection instrument. In general, samples for uranium analysis are preconcentrated by evaporation, air-, freeze-, or oven-drying to remove water, and dry-ashing or wet-ashing to remove carbonaceous matter. For vegetation and soil, acid or alkali fusion followed by acid dissolution of the fusion cake is required to ensure dissolution of refractory materials. Aerosol, water, soft tissues, blood, and dry-ashed bone samples may be solubilized with mineral acids. 

Some work [5] has been performed on the photochemical reaction between sulfur dioxide and hydrocarbons, both paraffins and olefins. In all cases, mists were found, and these mists settled out in the reaction vessels as oils with the characteristics of sulfuric acids. Because of the small amounts of materials formed, great problems arise in elucidating particular steps. When NO and 02 are added to this system, the situation is most complex. Bulfalini [3] sums up the status in this way The aerosol formed from mixtures of the lower hydrocarbons with NO and S02 is predominantly sulfuric acid, whereas the higher olefin hydrocarbons appear to produce carbonaceous aerosols also, possibly organic acids, sulfonic or sulfuric acids, nitrate-esters, etc. ... 

---