Modifications to an H₂S Tape Sampler for Increasing Sensitivity and Accuracy in H₂S Sampling

Trace sulfur determination in petroleum fractions

“…strip) decreases at very low concentrations as indicated by several other investigators (7,8). Therefore, calibration should be done with standard blends which fall in the same concentration range as the samples.…”

“…Therefore, calibration should be done with standard blends which fall in the same concentration range as the samples. Use of the hot humidifier containing 1% aqueous acetic acid, as discussed previously, tended to maintain high efficiency in sulfide formation in contrast to air monitoring studies (7,8) in which optimum conditions may not have maintained. Instability of the PbS in the presence of light has been mentioned by other researchers (7-9) involved in air monitoring.…”

“…This is a significant response with respect to noise level because the response is taken as the average (including noise) over the last several minutes of the injection period. Actually, noise level can be reduced appreciably by using a storage battery to power the tungsten bulb light source such that a significant signal to noise response can be obtained with concentrations as low as [5][6][7][8][9][10] ng S/mL. Without such modification, the limit of detection is about 25 ng S/mL.…”

Ambient Air Monitoring for Sulfur Compounds

“…Some of these errors were minimized by changes recommended by Siev et al 69 Lamp voltage was reduced to 60 volts, relative humidity of incoming air was increased to 80% by bubbling through 2% H2SO4, SO 2 interference was removed by inclusion of a barium acetate trap, and new calibration curves were drawn up. Sensitivity was increased to about 20 ppb.…”

Comparison of Hydrogen Sulfide Analysis Techniques

“…This can be accomplished by passing the tape over a weak H 2 SO 4 solution just prior to exposure to the sample. 9 ; 13 The incorporation of glycerol into the tape impregnating reagent does not appreciably affect the sensitivity of the method. 13 It does, however, provide sufficiently high humidity in the exposure chamber so that realistic data can be obtained in the event of humidifier malfunction in unattended field operations.…”