Coal dust analyses

Eumstead ( ) chose native fluorite as an internal standard for the analysis of quartz in coal dust His procedure consisted of mixing 0 20 mg fluorite into each water suspension of standard and sample and depositing on silver membrane filters for a calibration curve (fluorite/quartz intensity ratio i[ . mg quartz) The application of this method to coal dust samples containing less than 1% quartz produced acceptable results relative standard deviation (RSD) was 18 2 ... 

Germanium was determined in coal dust after conversion into the chloride [604] by treatment with hydrogen chloride at a high temperature on a mixture of coal powder and Chromosorb (1 1), wetted with sulphuric acid. The analysis of a sample of 1.5 g was reported having a sensitivity of 3.3 ppm of germanium with an error of 6%. 

Wankhade HK, Garg AN. 1989. Neutron-activation analysis of coal dust particulates and atmospheric pollution. Indian J Environ Health 31(2) 125-130. 

FOLLOW-UP PROBLEM 3.5 One of the most widespread environmental carcinogens (cancer-causing agents) is benzo[a]pyrene (J/t = 252.30 g/mol). It is found in coal dust, in cigarette smoke, and even in charcoal-grilled meat. Analysis of this hydrocarbon shows 95.21 mass % C and 4.79 mass % H. What is the molecular formula of benzo[a]pyrene ... 

Source Apportionment Assume that for a rural site the measured PM 0 concentration is 32jig m-3 containing 2.58 pgm-3 Si and 3.84pgm 3Fe. The two major sources contributing to the location s particulate concentration are a coal-fired power plant and soil-related dust. Analysis of the emissions of these sources indicates that the soil contains 200 mg(Si) g (20% of the total emissions) and 32 mg(Fe) g 1 (3.2% of the total emissions), while the particles emitted by the power plant contain IOmg(Si)g (1%) and 150mg(Fe)g (15%). Neglecting Si and Ft contributions from other sources... 

Most analysis conforms to the status quo of the damage that coal dust causes to health, including the morbidity, and mortality of pneumoconiosis. 

However, most of these studies conduct a qualitative discussion of the damage that coal dust does to the health of miners. Consequently, they lack a systematic theoretical and empirical analysis, and quantitative evaluation of the risk factors. 

Very little data have been reported on the analysis of elements in whole coal and mine dusts in particular. Kessler, Sharkey, and Friedel analyzed trace elements in coal from mines in 10 coal seams located in Pennsylvania, West Virginia, Virginia, Colorado, and Utah (5). Sixty-four elements ranging in concentration from 0.01 to 41,000 ppm wt were determined. Several surveys published previously have provided data on the concentration of minor elements in ashes from coals rather than a direct determination on the whole coals or mine dusts. Previous investigations include studies by Headlee and Hunter (6), Nunn, Lovell, and Wright (7), Abernethy, Peterson, and Gibson (8), and others (9, 10, 11,12). 

Contamination is a problem one always faces in trace analysis. Mercury is ubiquitous in many laboratories, as is fluoride. Lead is present in dust, particularly in laboratories located close to heavy automobile traffic. Extreme caution must always be exercised as contamination on the trace level may come from unexpected sources. Table I shows that using manganese steel in the jaws used to crush the coal increased the manganese content of the crushed coal more than twofold. 

Paulownia charcoal. A light powder, which is easily scattered and has an apparent specific gravity of 0.12 g/cc. This value is the lowest for all the kinds of charcoal at present available. The dye adsorption power in water lies between pine charcoal, and hemp coal which has the largest. One analysis showed that it contained. 9% moisture and 2.5% ash. The pH value of the wash water(5 grams of charcoal / 30cc of water) was 7 5 A mixture of the paulownia charcoal, sulphur and potassium nitrate burns as well as the pine charcoal, but it produces less fire dust than the pine charcoal. 

The potential of ultrasonic extraction for field-based extractions has been put into use in the industrial hygiene and environmental single-element analysis of, for example, lead from glass fibre filter ambient air samples [13,14] or from lead-based paint, urban dust and river sediment [15] hexavalent chromium from coal fly ash and paint chips [16] and strontium from river sediment [17]. Ultrasonic extraction has also proved effective as a prior step in multi-element determinations of heavy metals. 

---