Estudo da influência do processo de secagem da biomassa casca de palma forrageira (Opuntia ficus) na remoção de gasolina em corpos d'água, utilizando o sistema de adsorção em leito diferencial.

Abstract

Accidents in oil industry and gas stations have occurred very frequently, with contamination with hydrogen carbon compounds in both soil and aquatic systems. Among technologies available in recovery of waters contaminated with petroleum compounds, one of most used is adsorption, a process based on ability of some solids to remove soluble substances. Search for low cost adsorbents has presented biomass as attractive and sustainable options for treatment of various types of effluents. Therefore, objective of this work was to evaluate adsorptive efficiency of cactus pear forage palm bark biomass (Opuntia ficus-indica) obtained from two drying processes, when used to remove gasoline from water bodies using adsorption differential bed system. Mmethodology used was proposed by Lima et al. (2014). Initially, biomass was prepared in particulate form using Tyler Series sieves. Subsequently, experiments were performed to study adsorption kinetics, in which times from 05 to 60 minutes (with 5-minute intervals) and adsorption equilibrium were evaluated, whose contaminant concentrations ranged from 5 to 60% (with rate of change of 5%). For differential bed system concentrations of 5%, 7.5% and 10% of pollutant were used. Results confirmed that gasoline adsorption kinetics was fast through biomass obtained in different drying methods, with little influence. Equilibrium isotherms also showed maximum adsorption capacity values close to each other, with maximum values of 8.61 g.g-1 and 8.67 g.g-1 for naturally dried and oven dried biomass, respectively. In differential bed system, biomasses dried at different temperatures presented efficiency in adsorption process; However, naturally dry biomass resulted in a maximum percentage of adsorption at contaminant concentrations of 5% and 7.5%. Thus, it can be confirmed by results obtained that cactus pear forage bark obtained by two drying processes presents as an adsorbent biomass for removal of petroleum-derived compounds present in water bodies, being indicated drying at room temperature, as there is less energy expenditure, resulting in a better cost-benefit ratio.