Conversion of Lignin-Nanofibers to CNFs

In this study, a novel method, electrospinning, was used to prepare lignin-based carbon nanofibers. The major material was lignin. The chemical and thermal properties of different lignins were characterized to determine their suitability for partial incorporation of polyacrylonitrile (PAN). Then the precursor fibers were carbonized at a temperature from 600 degrees C to 1000 degrees C, respectively to prepare biomass-based carbon nanofibers. The influences of carbonization temperature on prepared carbon nano fibers were investigated by X-ray diffraction (XRD), Raman, thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The results indicated that the diameter of prepared precursor fibers and carbon fibers were about 200 nm and 100 nm, respectively. The increase of temperature has little influence on the carbon fibers graphitization degree. The D band of the carbon fibers carbonized at 900 degrees C is lowest. The thermal stability of the carbon fibers changes little with rising temperature when carbonized temperature exceeds 900 degrees C, and carbon fibers carbonized under 900 degrees C have most compact structure. Therefore, the above conclusions make clearly that 900 degrees C is the optimal carbonization temperature for preparing lignin-based carbon nanofibers in this technique. Meanwhile, the study is a doubled-edged enterprise that aims to recycle the waste from pulping industry as well as to turn it into a valuable material.