Avaliação da eficiência da adsorção em leito diferencial, utilizando casa de palma forrageira (opuntia stricta) como biossorvente, na remoção de contaminantes orgânicos em corpos d'água.

Abstract

There are many factors that contribute to environmental pollution, among them petroleum industries, which are considered worldwide as one of sectors that provides most contamination of the environment. Throughout their production process, these industries are responsible for generating huge amounts of solid, directly damaging survival of life on the planet. Among the processes used for decontamination of these effluents, is adsorption process, which uses biomass as adsorbents and has been shown to be quite efficient. Present work proposed an alternative for removal of gasoline from effluents by means of adsorptive processes, using as adsorbent cactus pear forage peel (Opuntia stricta), a typical species of northeastern semi-arid. On methodology used, biomass in particulate form was obtained after drying step. This was followed by adsorption kinetics study, in which times from 5 to 60 minutes (at 5-minute intervals) and equilibrium, whose contaminant concentrations ranged from 5 to 60% (with a rate of change of 5 %). For differential bed, concentrations of 10%, 15% and 20% were used. As a result, adsorption kinetics were observed to be rapid, with adsorption efficiency being higher in the first minutes of experiment, and maximum adsorbed capacity of 7.36 g.g-1. At equilibrium, maximum adsorption capacity was 11.11 g.g-1. For study in differential bed system, percentage of adsorption for contaminant concentration equal to 10% was highest (residual volume of 6.64 mL), with adsorption efficiency increasing with increase of contact time biomass/contaminated solution. For other concentrations (15 and 20%), the same adsorption profile was followed, although adsorptive capacity decreased. Thus, it is valid to confirm adsorptive efficiency of biomass of cactus pear forage peel (Opuntia stricta), thus characterizing an alternative, economical and sustainable source for removal of effluents contaminated by gasoline.