Uso de materiales litológicos oxídicos para la reducción de la dureza en aguas naturales.

The main objective of this study was to assess hardness reduction of natural water by using variable load substrates from two oxidic lithological materials (OLM), namely “C Material” and “L Material,” that were collected from natural deposits in Venezuela. Adsorption tests were performed with natural substrates that were activated with NaOH. The results revealed the presence of amphoteric iron, silicon, and aluminium oxides in their structures. Column experiments show a retention capacity of 12.51 and 11.02 mgCaCO3/kg for Materials L and C, respectively. Activation increased 2.5 times the yield of the process, 29.28 mgCa2+/kg for Material L and 26.94 mgCa2+ /kg for Material C, due to increases in the density of surface negative charges. The adsorption was non-specific and the data conformed to the Freundlich model. It is concluded that the materials examined are excellent options for treating water hardness. [ABSTRACT FROM AUTHOR]