Caracterização e avaliação das fibras de paina (Ceiba pentandra (L.) Gaertn) do nordeste brasileiro na sorção de óleo diesel

Abstract

Considering the high demand for transportation and storage of oil and oil products, the problem of spills in water bodies has been frequent in the world, and with serious damage to marine fauna and flora. Thus, numerous environmental remediation and oil recovery methods have been developed, where the use of sorbent materials stands out due to the low cost, high recovery efficiency and regenerative capacity. Among the natural sorbents, the kapok fibers (Ceiba pentandra (L.) Gaertn) are distinguished for being materials from agricultural origin and have characteristics of oleophilicity (oil affinity), hydrophobicity (water aversion), good buoyancy and, for being biomass, also present biodegradability. Therefore, in this work the diesel oil sorption capacity of the kapok fibers (Ceiba pentandra (L.) Gaertn) from northeastern Brazil was tested by dripping test methodology. The material was characterized by Thermogravimetric Analysis (TGA / DTG), Infrared Spectroscopy with Fourier Transform (FTIR) and Photoluminescence Spectroscopy (PLE), and Scanning Electron Microscopy (SEM). The sorption kinetics of the kapok fibers and their stable oil capture potential were also evaluated even when subjected to agitation. Qualitative tests were performed to attest to the practical performance of the material against a single-phase diesel and two-phase system (diesel and water). To understand the functional contributions of the surface in the sorptive process, it was subjected to extraction of its waxy content and its subsequent characterization in Gas Chromatography with Mass Spectrometry (GC-MS), and the material post-extracted to a new sorption test. Natural fibers showed high sorptive potential, within an average of 58.5 g of diesel / g of sorbent, and sorption kinetics indicated rapid rate within the first 10 seconds of contact, and the material was exceptionally stable, maintaining 86% of the oil retained after agitation by 30 minutes. The characterizations proved, the functional oleophilicity and a fluorescent character in the region at 390 to 400 nm. A tubular microfibrous morphology was also verified, which suggested great porosity and buoyancy. The extraction of the superficial waxes indicated that they are directly linked to the oleophilic potential of the fibers with alkane and aromatic groups, but they do not have shown great contribution in the sorptive capacity, being the morphology of the fibers the most determining factor for this process.