Obtenção de sílica mesoporosa utilizando óleos naturais como agentes modificadores de estruturas

Abstract

The search for natural and renewable sources for the production of new materials has been increasing over the last years due to a possible lack of fossils resources, prices variation of petrol and the concerning about the environment. In this context, this work aims the study over the influence of natural oils (sucupira and copaiba) as a structure modifier agent in mesoporous silica matrices. For this, matrices were prepared by template methodology from the Sol-Gel process using the nonionic surfactant tween 80 as a structure directing agent, the alkoxide Tetraethyl orthosilicate as a source of silicon and natural oils were used as structure-modifying agents. Besides, the influence of hydrothermal treatment in the textural properties was also evaluated. From the results obtained, it could be observed that the samples present a N2 adsorption-desorption isotherm featuring mesoporous materials with high surface areas and porous volume. Besides this, the hydrothermal treatment caused an expansion of about 100% of the porous diameter and the increasing of the porous volume of about 300% in relation to the untreated samples; while the use of natural oils as structure modifier agents leaded to the obtainment of materials with different characteristics from those ones on standard samples. The materials prepared from the use of sucupira oil presented an increasing of about 35% over the specific surface area, and increased the porous volume in 18%. On the other hand, the use of copaiba oil leaded to the formation of materials with a reduction of values of about 28 and 45% for the porous diameter and the porous volume, respectively. Thus, the use of sucupira and copaiba oil as structure modifier agents on the replacement of petrol derivative compounds is clearly viable, since they influence on matrices final properties, they also present a high extraction quantity, great availability, easy acquisition and low cost.