Qualitative and Quantitative Analysis of Soils Using Laser-Induced Breakdown Spectroscopy and Chemometrics Tools

Autor(es)

Costa, V. C. ^{[1, 2]} ; Ferreira, S. dos Santos ^[3] ; Santos, L. N. ^[3] ; Speranca, M. A. ^[1] ; da Silva, C. Santos ^[1] ; Sodre, G. A. ^[3] ; Pereira-Filho, E. R. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Chem, Grp Appl Instrumental Anal, BR-13565905 Sao Carlos, SP - Brazil

^[2] Fed Univ Alfenas Unifal, Lab Toxicant & Drug Anal LATF, BR-37130000 Alfenas, MG - Brazil

^[3] Univ Estadual Santa Cruz, BR-45662900 Ilheus, BA - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Spectroscopy; v. 87, n. 2, p. 378-386, MAY 2020.
• Citações Web of Science: 0

Resumo

In the present work a method was proposed for the direct determination of Ca, Fe, K, and Mg and qualitative analysis of anthropized and cabruca soil samples from different depths (0-20 and 20-40 cm) by laser-induced breakdown spectroscopy (LIBS). The LIBS instrumental parameters were evaluated using a central composite design with a central point. The variables evaluated were as follows: delay time in five levels (0.5, 0.7, 1.2, 1.7, and 1.9 mu s) and fluence at five levels (1448, 1811, 2659, 3514, and 3820 J center dot cm(-2)). The best results obtained were with a delay time of 1.2 mu s and fluence of 2659 J x cm(-2). The proposed calibration model for Ca, Fe, K, and Mg obtained using LIBS data presented a good correlation with the reference values obtained by inductively coupled plasma atomic emission spectrometry (ICP OES). In addition, multivariate data analysis from LIBS spectra in the region of 186-1042 nm was performed using principal component analysis (PCA). From the LIBS spectra it was possible to discriminate the different analyzed samples, showing that the combination of LIBS with PCA is an excellent option for the discrimination of soils. (AU)

• Processo FAPESP: 16/01513-0 - Combinação de LIBS (Laser-Induced Breakdown Spectroscopy) e ICP OES (Inductively Coupled Plasma Optical Emission Spectrometry) na análise de amostras de resíduo eletrônico (circuito eletrônico e polímeros), alimentos e líquidas de difícil preparação
• Beneficiário: Edenir Rodrigues Pereira Filho
• Modalidade de apoio: Auxílio à Pesquisa - Regular