X-Ray Fluorescence Analysis of Ground Coffee

MARÍA CRISTINA HERNÁNDEZ1 , DARÍO ROMERO1 , HUMBERTO TORRES1 , JAVIER MIRANDA2,3*, AND A. ENRIQUE HERNÁNDEZ-LÓPEZ2

1 Facultad de Ciencias, Universidad Nacional Autónoma de México, Circuito Exterior, 04510, Coyoacán, Cd. Mx., MEXICO

2 Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20- 364, 01000 Álvaro Obregón, Cd. Mx., MEXICO 3 Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Circuito Investigación Científica, 04510, Coyoacán, Cd. Mx., MEXICO

*Email: miranda@fisica.unam.mx

Abstract :

Coffee is becoming one of the most popular beverages in Mexico. In the present work, X-ray Fluorescence (XRF) was used to determine the contents of several elements (with atomic numbers between 11 and 38) in 11 samples of commercial ground coffee, comparing with another one of soluble coffee and two of used ground coffee. Samples were dried at room temperature and pelletized. XRF analyses were carried out using a spectrometer based on an Rh X-ray tube, registering the characteristic x-rays with a Silicon Drift Detector. The system detection calibration and accuracy check was performed through the analysis of NIST certified reference materials 1547 (peach leaves), 1570a (spinach leaves), 1573a (tomato leaves), and 1571 (orchid leaves). As a general rule, the elemental concentrations measured are similar in all samples of coffee, in values not exceeding toxic levels. However, the differences among the elemental concentrations are shown.

DOI: https://doi.org/10.15415/jnp.2017.51003

LINK: http://dspace.chitkara.edu.in/jspui/bitstream/1/863/1/51003_JNP_Miranda.pdf

X-Ray Fluorescence Analysis of Fine Atmospheric Aerosols from a Site in Mexico City

DOI

10.15415/jnp.2016.41003

AUTHORS

A. E. Hernández-López, J. Miranda, J. C. Pineda

ABSTRACT

A study was performed in the Winter of the year 2015 in a Southwestern site in the MAMC (Ciudad Universitaria), collecting PM2.5 samples with a MiniVol. As a part of wider study focused to fully characterize aerosols at this site, an X-ray Fluorescence (XRF) spectrometer (based on an Rh X-ray tube) built to analyze environmental samples, was used to characterize the sample set. A total of 16 elements (Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, and Pb) were detected in most samples and mean concentrations were calculated. Cluster analysis was also applied to the elemental concentrations to find possible correlations among the elements.

KEYWORDS

XRF, atmospheric aerosols

REFERENCES

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