The H₂S online detection in gaseous media using diode laser absorption spectroscopy in the range of 4860–4880 cm⁻¹

Abstract

This paper reports on experimental measurement of H2S absorption in the spectral range of 4860–4880 cm−1 by means of diode laser absorption spectroscopy, and determines the H2S spectral absorption line in the generation area of the laser used, most promising in terms of H2S detection using this method.

Application of TDLAS for measuring absorption coefficients of H2S rotational absorption lines near the wavelength of 2 µm

“…For experimental measurement of hydrogen sulfide absorption coefficients, the same experimental setup was used as in [2,13], as well as in a number of our other works.…”

“…As noted in our previous papers [1,2], the objective of developing a method for real-time detection of hydrogen sulfide (H 2 S) in gaseous media (in man-made emissions of industrial enterprises, in residential areas) is an important practical problem, in particular, for the gas, food industry, agriculture, environmental monitoring, etc. This is due to the fact that, being a highly dangerous toxic substance [3], hydrogen sulfide, when ingested into the human body, can cause pulmonary edema with the subsequent development of paralysis.…”

“…One of the promising methods of real-time detection of H 2 S in gases is the tunable diode laser absorption spectroscopy (TDLAS) technique using tunable diodes lasers (TDL) emitting in the near and middle infrared spectral ranges [10][11][12]. This technique has been successfully used in our previous works to measure the ratio of 13 C/ 12 C in exhaled air for diagnosing gastrointestinal tract diseases [13]; as well as to investigate the possibility of detecting hydrogen sulfide in gaseous media [2].…”

“…Experimental studies conducted in [2] have shown that one of the spectral ranges that can be used for detecting H 2 S using the TDLAS technique is the 4860-4880 cm −1 region, which contains a number of hydrogen sulfide absorption lines that overlap minimally with each other and with other components of the analyzed gas mixture; to which atmospheric carbon dioxide and water vapor relate in the first place. In this paper, 2 rotational absorption lines of hydrogen sulfide were determined-Line 2 (central frequency ν 02 = 4864.8 cm −1 ) and Line 4 (central frequency ν 04 = 4875.2 cm −1 ) which belong to the vibrational transition of 021-000; the most suitable ones for measuring the content of hydrogen sulfide in gaseous media (the designation of the lines corresponds to the paper [2]). To accurately measure the hydrogen sulfide content in the analyzed mixture, it is necessary to determine the values of its absorption coefficients in the centers of the selected lines and, since measurements can be carried out at different pressures, their dependences on the pressure of the analyzed gas mixture.…”

Применение Метода Абсорбционной Диодной Лазерной Спектроскопии Для Измерения Содержания -=sup=-13-=/Sup=-С И -=sup=-12-=/Sup=-С В Выдыхаемом Воздухе

“…Имеется большое количество способов измерения 13 С 16 О 2 в выдыхаемом воздухе [11]. Среди них одним из наиболее перспективных, позволяющих достигать высокие чувствительность и точность в реальном мас-штабе времени, является способ, основанный на методе абсорбционной лазерной спектроскопии, в котором применяются в качестве источников частотно перестраиваемые диодные лазеры [12][13][14][15][16][17][18][19][20], которые излучают в ближнем и среднем инфракрасных спектральных диапазонах, где у 12 С 16 О 2 и 13 С 16 О 2 имеются интенсивные полосы поглощения. Этот способ получил общепринятое наименование TDLAS (tunable diode laser spectroscopy).…”