Desenvolvimento de um amostrador passivo e o uso da fibra da Ceiba pentandra (L.) Gaertn como biosorvente de compostos orgânicos voláteis - COVs do ar

Abstract

Pollutants in the atmosphere are mainly related to large emission from the vehicles automotive and fuel service stations. This study aimed to develop a model of passive sampler and biosorbent for Volatile Organic Compounds - VOCs specific for application in environmental monitoring studies of air quality. This study evaluated the use of passive samplers for environmental monitoring of VOCs and benzene in particular, due to its high toxicity. The International Agency Research on Cancer (IARC/WHO) classifies benzene in the Group 1, that is as a chemical substance with sufficient evidence of its carcinogenicity in humans. Sorption studies of VOC in fiber Ceiba pentandra active constituent of passive samplers were held in the Laboratório de Tecnologia Ambiental- Labtam (UFRN) and a fuel service station in the city of Natal-RN. The samples were analyzed using a Thermal Desorption coupled to a gas chromatograph with a mass detector (GC/SM). The sampling method using diffusive passive samplers and VOC analysis through of pyrolysis method (GC/SM) proposed in this work, was an adaptation of the TO-17 method from the Environmental Protection Agency - United States Environmental Protection Agency. This proposed method allowed to identify the presence of VOC compounds in ambient air. From the results obtained in the laboratory and in the field, empirical correlations have been proposed to correlate the concentrations of the pollutants with the peak areas obtained from the GC/MS. This correlation proposal can be used to obtain good results in different locations and seasons. The biosorbent activated fiber Ceiba pentandra, confirmed by the results of the specific area (BET), degradation temperature (TG/DTG) and the hydrophobicity of the material, its qualities on the VOC sampling the air, which in addition to protecting the analyte system of any amounts of water, showed low noise levels in the elution range studied in the GC/SM. The sampling method which utilizes passive diffusive samplers allows identifying the presence of benzene in the simulated experiments in laboratory, but also in ambient air. Based on the results observed in this research, innovative environmental technologies should be implemented to contribute to the reduction of occupational hazards caused by VOC in the supply operations in fuel service stations in order to protect the health of gas station attendants. Importantly, the results observed during this research should be viewed as indicative and not conclusive, because one greater monitoring is needed so that definitive conclusions can be elaborated.