Sulfamethoxazole sorption in eutrophic Regolithic Neosol/Sorcao do sulfametoxazol em Neossolo Regolitico eutrofico

• Published in: Revista brasileira de engenharia agrícola e ambiental Vol. 22; no. 7; p. 506
• Main Authors: Barros, Marcia A.M.F. de, Antonino, Antonio C.D, Schuler, Alexandre R.P, S. Lima, Jose R. de, Gondim, Manuella V.S, Lima, Valmir F. de
• Format: Journal Article
• Language: English
• Published: ATECEL--Associacao Tecnico Cientifica Ernesto Luiz de Oliveira Junior 01.07.2018
• Subjects: Brasil
• ISSN: 1415-4366; 1807-1929
• DOI: 10.1590/1807-1929/agriambi.v22n7p506-510

This study aimed to evaluate sulfamethoxazole sorption kinetics and isotherms using batch method. The experiment was carried out in typic eutrophic Regolithic Neosol (0-20 and 2060 cm layers) located in the private reserve of the Riacho do Papagaio farm, in Sao Joao, PE, Brazil. The tests were carried out under laboratory conditions at 24[degrees]C and sulfamethoxazole concentration was determined by high-performance liquid chromatography. The sorption experiment through the batch method used sulfamethoxazole solutions with concentrations of [10.sup.-3], 5.[10.sup.-4], [10.sup.-4], 5.[10.sup.-5], [10.sup.-5] and 5.[10.sup.-6] mol [L.sup.-1] to obtain the analytical curve. For this soil, sulfamethoxazole sorption kinetics was best described by a second-order model and the sorption isotherms were linear. Sulfamethoxazole predominantly interacts with organic matter in this type of soil. The results obtained in this study show that the antibiotic sulfamethoxazole exhibits low adsorption, posing a higher risk of contamination to the groundwaters in this region at pH [approximately equal to] 7. Key words: soil contamination interaction adsorption Objetivou-se neste estudo avaliar a sorcao do sulfametoxazol, onde a cinetica e as isotermas de sorcao foram determinadas em duas camadas de solo Neossolo Regolitico Eutrofico tipico (camadas 0-20 e 20-60 cm) da reserva particular da fazenda Riacho do Papagaio, Sao Joao, PE. Os ensaios foram realizados em laboratorio a 24[degrees]C, pelo metodo "batch", e a concentracao de sulfametoxazol determinada por cromatografia liquida de alta eficiencia. Nos ensaios de cinetica de sorcao foi utilizada solucao de sulfametoxazol na concentracao de [10.sup.-4] mol [L.sup.-1], enquanto para as isotermas de sorcao foram utilizadas solucoes nas concentracoes de [10.sup.-3], 5.[10.sup.-4], [10.sup.-4], 5.[10.sup.-5], [10.sup.-5] e 5.[10.sup.-6] mol [L.sup.-1]. Para esse solo, as cineticas de sorcao do sulfametoxazol foram melhor descritas com um modelo de segunda ordem e as isotermas de sorcao foram lineares. Para este tipo de solo, a interacao do sulfametoxazol e predominantemente com a materia organica, apresentando baixa adsorcao, evidenciando um maior risco de contaminacao das aguas subterraneas existentes nessa regiao em pH [approximately equal to] 7. Palavras-chave: contaminacao do solo interacao adsorcao