Spectroscopic and Microscopic Characterization of Volcanic Ash from Puyehue-(Chile) Eruption: Preliminary Approach for the Application in the Arsenic Removal

Table 2

Major and minor elements (expressed as % oxides) by ICP AES.

Sample	PM	PT	ST
SiO2	67.03	70.30	60.52
TiO2	0.89	0.65	1.17
Al2O3	14.17	13.35	14.52
Fe2O3	5.58	4.56	8.92
MnO	0.14	0.12	0.16
MgO	1.05	0.56	2.77
CaO	2.95	2.02	5.76
Na2O	5.04	5.12	3.77
K2O	2.37	2.52	1.49
P2O5	0.17	0.13	0.33
Cr2O3	0.01	0.01	0.01
BaO	0.08	0.08	0.05
SrO	0.02	0.02	0.04
LOI	0.50	0.56	0.49

PM: volcanic pyroclastic mixture; ST: scoria type; PT: pumiceous type.