Capitulo 7. Aplicación de técnicas de uso corriente en metalurgia extractiva para la remediación de sitios contaminados por la minería y por otras actividades antropogénicas

VIDAL NURIA Y VOLZONE CRISTINA

Libro de las XI Jornadas Argentinas de Tratamiento de Minerales

Universidad Nacional de Comahue

Lugar: Neuquén; Año: 2012; p. 403 - 408

Toluene is a chemical that occurs naturally in crude oil or secreted by the tolu tree (Myroxylon toluifera). It is considered an excellent organic solvent present in cigarette smoke, in adhesives, paints, gasoline, dyes, paints, etc. Intoxication with toluene cause disorders at the level of central nervous system, liver and kidneys. The effluents from chemical and petrochemical industries may contain different amounts of toluene (maximum 800 mg L-1). In recent years, interest in the care of the natural environment and aim to remove the most contaminants presents in effluents, has generated an investigation and propose solid materials easy to handle and cheap design. Among these materials are clays, which are solid naturally abundant, small particle size (less than 0.0002 cm), and laminar structure. These characteristics give properties as adsorbents and can retain contaminants between the sheets. In this work natural clay was modified with an organic salt, converting it to organoclay, being it suitable to retain toluene in water. The basic structure of this salt is a tetrahedron of 4 carbon atoms and with an ammonium center. The quantification of toluene retained by each sample was determined using a UV-visible spectrometric equipment Hewlett-Packard 8435, analyzing the toluene solution before and after contact with the solids. Natural clay and modified before and after retaining toluene, was characterized by X-ray diffraction (XRD) and thermal analysis (DTG and TG). It has been observed that the presence of toluene produced changes in the initial properties of the clay and the organoclays. These changes were evident in the variations in the thermogram (exo-endothermic peaks changes) and in the diffractograms (changes in interlaminar spacing, intensity of reflection 001, etc.). These variations helped to analyze and evaluate the thermal stability of natural clay and organoclay with toluene associated.