Interação físico-química da amoxicilina em um neossolo quartzarênico do Parque Nacional do Catimbau, Pernambuco

Abstract

In the Parque Nacional do Catimbau, located in the semi-arid region of Pernambuco, some soils considered endemic were identified due to their peculiar characteristics. Pedogenetic studies are seeking to identify the processes that gave rise to these soils, relating them to those that gave rise to the soils known as "Terra Preta de Índio". The differentiated behavior of the Terra Preta de Índio is attributed to the presence of biochar, which gives the soil retention of organic compounds properties. The presence of antibiotics in the environment, even at low concentrations, is related to the development of resistant bacteria. Amoxicillin is a drug widely used because of its high efficiency in the treatment of human and veterinary disorders. This papper aims to evaluate the physical-chemical interaction of the Neossolo Quartzarênico of the Parque Nacional do Catimbau with the antibiotic amoxicillin. Its capacity of organic compounds retention was determined by adjusting the data to the kinetic models of pseudo first order and pseudo second order and the Langmuir, Freundlich and Sips isotherms. In the isotherm test, concentrations between 5 mg L-1 and 200 mg L-1 were used. The pseudo first order model fitted better to the data, suggesting the predominance of the physical adsorption. The data obtained for the lower concentrations of amoxicillin were better adjusted to the Langmuir isotherm, while for higher concentrations, the Freundlich isotherm became more adequate. The equilibrium capacity obtained in this work was low when compared to the other adsorption studies of amoxicillin in biochar, indicating that the studied soil does not have a good adsorptive capacity.