Síntese e caracterização de nanotubo de carbono derivado de lignina extraída do mesocarpo do dendê (Elaeis guineensis)

Abstract

With the discovery of Carbon single-wall nanotubes (SWNT’s) by Sumio Iijima in 1991, the researchers were interested in synthesizing CNT’s on a large scale, with quality and low cost. This work proposes a new methodology and ecologically correct for the synthesis of CNT’s by lignin pyrolysis extracted from the mesocarp of palm oil (Elaeis guineensis). To obtain the sample, the lignin was pyrolyzed in a tubular furnace 1.000°C with a given heating rate 10°C/min and the experiments were performed at different temperature ranges and under argon gas flow. After the synthesis process, the formation of carbon nanomaterials were verified. The CNT’s were subjected to functionalization in solution (3:1) of sulfuric acid (H2SO4) and nitric acid (HNO3) under stirring, added ammonia hydroxide (NH4OH) and washed, then neutralized. The nanotubes were also functionalized with chitosan. The final material was characterized by the surface area, structural and physical-chemical properties, using X-ray Diffraction (XRD), Thermal Analysis (TGA/DTA), Raman Spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR) Attenuated Total Reflection (ATR) spectroscopy and Electroanalysis through Cyclic Voltammetry and Impedance. The results showed that the pyrolysis process under argon flux obtained nanotubes with mean diameters of 7 nm with potential application.