EVALUATION OF NATURAL CLAY FROM CHACO AS AN ADSORBENT IN THE TREATMENT OF WATER CONTAMINATED WITH ARSENIC

Abstract

The increase in the concentration of arsenic (As) in the water available for human consumption has become a global problem. This fact requires the design of treatment systems aimed at minimizing the concentration of this metal and mitigating its effects, for which the present work aimed to evaluate the adsorption capacity of As from Chaco clay, from the Arequipa region in Peru, for the purification of contaminated water from mining effluents. This evaluation was based on fitting the Freundlich and Langmuir adsorption isotherms using a jar system. The conditions of temperature, pH and mass of adsorbent solid used were defined from an initial exploratory experiment. The best removal capacity was obtained for the combination of pH, temperature and solid mass at 3, 18 ºC and 1.2 g respectively; the best fit was for the Langmuir model with an R² of 0.986 and a maximum adsorption capacity of 3.543 mg/g, considered acceptable. It was concluded that the parameters of the Langmuir model confirmed that the evaluated adsorption system can be viable for the removal of arsenic.

Keywords: adsorption, Chaco, arsenic, isotherms.