Enhancing elemental detection and characterization of magnetically confined water residue plasma through laser-induced breakdown spectroscopy

Abstract

This research explores the use of laser-induced breakdown spectroscopy to detect elements in water residue. This research focuses on inducing plasma on pelletized water residue samples via a pulsed Neodymium-doped yttrium aluminum garnet (Nd:YAG) nanosecond laser with a wavelength of 1064 nm and energy of 100 mJ. The LIBS measurements were performed without and with a magnetic field of 0.8 T. Magnetic discs were used to create a magnetic field of 0.8 T. The presence of different elements (Ca, Mg, Fe, Cr, Mn, As, C, Li, Sr, Ba, Ti, K, O, N, and Si) was confirmed by examining the plasma emission spectra obtained from LIBS analysis. The results show that LIBS successfully detected toxic and heavy metals in water residues. Notably, the presence of a magnetic field affects the plasma properties such that the electron temperature and electron number density increase with increasing magnetic field. The Joule heating effect and the magnetic confinement effect are responsible for the increase in the plasma properties. The improved spectroscopic outcomes are associated with the magnetic confinement of water residue plasma, supported by the affirmation of thermal beta β_t, which is less than one for all samples.