Bromine In Air Research Articles

Determination methods of bromine in air of workplace

To establish a spectrophotometric determination method of bromine in the air of workplace. Bromine in the air of workplace was absorbed by methyl orange solution, then determined by spectrophotometry. The range of the determination was 0.2 to 2.8 microg/ml, the linear equation was Y=0.0427X-0.0092, r=0.9996. The detection limit was 0.2 microg/ml. The minimum detectable concentration was 0.27 mg/m(3) for 7.5 L air sample. The relative standard deviations covered the range of 1.1% approximately 3.7%. The recovery rate was in the range of 93.6% to 97.2%. The sampling efficiency ranged from 93.5% to 100.0%. The method is available for the determination of bromine in the air of workplace.

Development of a Solid Sorbent Monitoring Method for Chlorine and Bromine in Air with Determination by Ion Chromatography

Abstract A solid sorbent sampling and analytical method for chlorine (Cl2) and bromine (Br2) in air, based on the reaction of halogen gases with silver to form silver halides, has been developed. The sampler uses an opaque, 25-mm cassette containing a Zefluor™ or polyester prefilter and a cleaned silver membrane filter. The silver halides are complexed with thiosulfate, releasing the halide ion, which is determined by ion chromotography. The method was laboratory evaluated using generated test atmospheres (room temperature, 20% and 80% relative humidities, and concentration levels of 0.1 to 2 times the Permissible Exposure Limit [PEL] set by the U.S. Occupational Safety and Health Administration [OSHA]), and field evaluated at a chlorine-containing industrial environment. Precision of the method was 7.2 percent, and the bias was insignificant (-1.3%). High humidity (∼80%) dramatically increased the capacity of the silver filter for Cl2 and Br2. Hydrogen chloride is a minor positive interference; however, ...

Determination of bromine in air by ion mobility spectrometry

An ion mobility spectrometer (IMS) was used to study the negative ion chemistry of bromine and monitor its concentration in a series of laboratory experiments and in the ambient air of a chemical production facility. Under the conditions of the IMS, three negative ions, Br −, Br 2 − and Br 3 −, were produced from bromine. The relative abundance of Br 3 − increased with the bromine concentration, whereas those of Br − and Br 2 − decreased owing to the ion-molecule reactions they undergo with bromine. The presence of chlorine, other bromides and chlorides did not adversely affect the determination of bromine. In all field measurements, the maximum bromine levels measured were below 30 ppb, well below its 8-h time-weighted average threshold limit value (TWA-TLV) of 100 ppb. The rapid response of the IMS was evident from the effect of changes in wind direction or velocity on the measured concentrations.

X-ray standing wave analysis for bromine chemisorbed on silicon

X-ray standing wave measurements on single crystals of silicon are used to determine the coverage and position of chemisorbed bromine. Detailed analysis of the position information leads to the conclusion that silicon surface atoms bonded to adsorbed bromine atoms are in extrapolated bulk-line positions. Direct measurement of the desorption of correlated bromine in air demonstrates the high stability of the Br/Si surface interface.