Photographic Analysis and Optical Diagnosis of Kilowatt Microwave Plasma Torch with Air Carrier Gas

Abstract

The spatiotemporal motion characteristics of the kilowatt argon microwave plasma torch with the air carrier gas (kW-AC-ArMPT) and the behavior of the plasma filaments are investigated with a digital single-lens reflex (SLR) camera and a high-speed camera. Along with the introduction of the air, both the volume of the central channel and the rotational frequency of the plasma filament are increased. Besides, the excitation temperature (T _exc), rotational temperature (T _rot), and density of electron number (n _e) of the kW-AC-ArMPT are measured with optical diagnosis. It is clearly shown that the introduction of air contributed to the rise of T _rot and n _e of the plasma, which is beneficial to improving the analytical performance of the plasma. Then the detection limits of some heavy metal elements are measured by kW-AC-ArMPT, which are in the ppb range. The experimental results show that the kW-ArMPT has a high tolerance to air injection at least 1.0 L/min, which allows the direct extraction of air from the environment for analysis and therefore has the potential for online and in-situ detection of ambient air quality and industrial exhaust gases.

Keywords

Air carrier gas / Microwave plasma torch / Photographic analysis / Optical diagnosis

References

[1] Jin Q, Wang F, Hieftje G M. Chem. J. Chinese Universities, 1990, 11: 1353.

[2] Jin W, Yu B, Zhu D, Ying Y, Yu H, Jin Q. Chem. J. Chinese Universities, 2015, 36(11): 2157.

[3] Yu B, Jin W, Zhu D, Ying Y, Yu H, Shan J, Xu C, Liu W, Jin Q. Chem. Research in Chinese Universities, 201, 32(4): 549.

[4] Zhu Z, Jiang T, Xiong X, Zou W. Rapid Commun. Mass Spectrom., 201, 30: 44.

[5] Jiang T, Xiong X, Wang S, Luo Y, Fei Q, Yu A, Zhu Z. Int. J. Mass Spectrom., 201, 399: 33.

[6] Jiang T, Jiang F, Zhuo Z, Liu H, Hu B, Li M, Li L, Huang Z, Zhou Z, Zhu Z. Analyst, 2021, 146(5): 1760.

[7] Zeng L, Wu M, Chen S, Zheng R, Rao Y, He X, Duan Y, Wang X. Talanta, 2022, 246: 123516.

[8] Jiang T, Peng Z, Xie M, Fang X, Hong Y, Huang Z, Gao W, Zhou Z, Li L, Zhu Z. Anal. Methods, 2020, 12(4): 535.

[9] Yu D, Wei H, Li Y, Shao Y, Jin W, Yu B. J. Anal. At. Spectrom., 2023, 38(7): 1402.

[10] Ying Y, Jin W, Yu B, Liu S, Wu X, Yu H, Shan J, Zhu D, Jin Q, Mu Y. Anal. Methods, 201, 8: 5079.

[11] Ying Y, Jin W, Yan Y, Mu Y, Jin Q. Chemometr. Intell. Lab. Syst., 2018, 176: 82.

[12] Duan Y, Su Y, Jin Z, Abeln S P. Anal. Chem., 2000, 72: 1672.

[13] Zhu D, Jin W, Yu B, Ying Y, Yu H, Shan J, Yan Y, Jin Q. J. Anal. At. Spectrom., 2017, 32: 1595.

[14] Yu B, Jin W, Ying Y, Yu H, Zhu D, Shan J, Liu W, Xu C, Jin Q. J. Anal. At. Spectrom., 201, 31: 759.

[15] Jankowski K J, Reszke E. Microwave Induced Plasma Analytical Spectrometry, 2010, London: Royal Society of Chemistry.

[16] Bruno B, Vincent G, Vincent M R, Rosalba G, Marcella D A, Alessandro D G. Spectrochim Acta Part B At. Spectrosc., 2023, 204: 106686.

[17] Wang S, Li G, Zhou J, Jin Q. Chem. Res. Chinese Universities, 200, 22(5): 560.

[18] Jin Q, Zhang H, Yu A, Duan Y, Lu X, Wang F. Anal. Sci., 1991, 7: 559.

[19] Giersz J, Bartosiak M, Jankowski K J. J. Anal. At. Spectrom., 2017, 32: 1885.

[20] Sesi N N, MacKenzie A, Shanks K E, Yang P, Hieftje G M. Spectrochim Acta Part B At. Spectrosc., 1994, 49: 1259.

[21] Li S, Chen C, Zhang X, Zhang J, Wang Y. Plasma Sources Sci. Technol., 2015, 24: 2.

[22] Masamba W, Ali A H, Winefordner J D. Spectrochim Acta Part B At. Spectrosc., 1992, 47: 481.

[23] Goode S R, Buddin N P, Chambers B, Baughman K W, Deavor J P. Spectrochim Acta Part B At. Spectrosc., 1985, 40: 317.

[24] Yu B W. Research on Fundamental Theory of Microwave Plasma Torch (MPT) and Development of Kilowatt MPT Spectrometer, 2016, Hangzhou: Zhejiang University

[25] Zhu D. Development of a Kilowatt Microwave Plasma Torch (MPT) Excitation Source for Atomic Emission Spectrometry, 2017, Hangzhou: Zhejiang University