Preparation and Characterization of Lignin Powder Micronized by a Supercritical Antisolvent (SAS) Process
Nanoscale lignin was successfully prepared with a supercritical antisolvent (SAS) apparatus using acetone as a solvent and superciritical carbon dioxide as an antisolvent. Four factors were studied and optimized by a four-level orthogonal array design (OAD). According to analysis of variance, precipitation pressure had a significant effect on mean particle size. The optimal conditions are as follows: precipitation temperature 35 °C, precipitation pressure 30 MPa, temperature difference +10 °C and concentration of lignin solution 0.5 mg/mL. The micronized lignin under the optimal conditions was characterized by Scanning Electron Microscopy (SEM), Fourier-transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and X-Ray Diffraction (XRD) analyses. The results showed the mean particle size of micronized lignin was 0.144 ± 0.03 μm and had no degradation. The solubility of micronized lignin was improved significantly in distilled water.
Zhong Cao, Lixian Sun, Xueqiang Cao, Yinghe He
Q. Lu et al., "Preparation and Characterization of Lignin Powder Micronized by a Supercritical Antisolvent (SAS) Process", Advanced Materials Research, Vols. 233-235, pp. 1642-1645, 2011