Analysis of the Atmosphere for Light Hydrocarbons

Comparison and Evaluation Methods for the Removal of Ethylene and Other Hydrocarbons from Air for Biological Studies

“…The catalysts tested (methods [20][21][22] can be used in various forms. Platinum is commercially available in a variety of concentrations on several different solid support materials, which may be in the form of granules, pellets, fibers, or powders.…”

“…The liquid traps (methods 10 and 11) consisted of 10 ml of reagent in a small gas-washing tube; the air was dispersed through a fritted glass aerator. The solid reactive materials (methods [12][13][14][15][16][17][18][19][20][21][22] were packed in a stainless steel tube (45 x 1.27 cm o.d.). Elevated temperatures, when required, were attained with a semimicrocombustion furnace (Sargent-Welch Scientific Co.) with a heating chamber 18 cm long.…”

“…Table II clearly shows that platinized asbestos, cupric oxideferric oxide pellets, and powdered cupric oxide maintained at high temperatures (methods [20][21][22] provide the most efficient means of removing hydrocarbons from a continuous air flow system without creating the problems encountered with adsorbent traps. These catalysts depend upon a constant supply of 02 for regeneration.…”

Ethylene Air Pollution

“…Highest levels of ethylene are found at ground level. Little difference in ethylene levels were observed in the first 100 feet (6,16), while smaller amounts were found at 3,000 feet (6). Other important point sources of ethylene are industry and fires.…”

“…Ambient levels of ethylene in unpolluted air vary between 1 and 5 nl/l (4,14,16), whereas in urban areas the levels increase to a maximum of approximately 130 nl/l (3,7,16 Automobiles account for 90% of the ethylene released in the air (Abeles et al, submitted for publication), and gas chromatographic analysis of urban air suggests that the atmosphere is essentially dilute auto exhaust with small amounts of photooxidants and SO2 added. Levels of ethylene vary with the amount of traffic, and a number of workers have shown that a peak in ethylene levels coincides with the morning rush hour (3,7,15).…”