Quality characterization and evaluation of bentonites from the provinces of San Juan and Río Negro (Argentina) for their use in the oil and ceramics industries

Abstract

The aim of this research work is to characterize bentonites, both physically and chemically, as well as mineralogically, from deposits located in the Argentine provinces of San Juan and Rio Negro. The study is completed with technological assays to evaluate the quality of the samples under study so as to determine possible industrial uses and/or applications for this material. To carry out this work, four samples of bentonite, identified as M1, M3, and M4, from the province of San Juan, and another, identified as M2, from the province of Rio Negro were used. Physical characterization consisted of determining: swelling, density, moisture, pH and specific gravity of the bentonite samples through application of a number of techniques. Chemical characterization of major components was carried out by using wet methods through acid attack, whilst ICP was used to characterize minor components. 79 Mineralogical characterization was carried out by using an infrared spectrometer. The technological assays for evaluating the quality of the bentonite were carried out following the method indicated by the API and SEGEMAR standards, among others, in order to determine possible uses and/or applications, mainly in the oil and ceramics industries. It was found that the M2 bentonite is the most suitable to be used as a drilling mud as it meets the requirements specified by the API standards. The M3 bentonite, due to its physico-chemical characteristics such as low rheology, swelling, low iron content, amongst others, is the most suitable for the ceramics industry.