Graphitic Biocarbon from Metal-Catalyzed Hydrothermal Carbonization of Lignin

Abstract

Lignin is a high-volume byproduct from the pulp and paper industry and is currently burned to generate electricity and process heat. The industry has been searching for high value-added uses of lignin to improve the process economics. In addition, battery manufacturers are seeking nonfossil sources of graphitic carbon for environmental sustainability. In this work, lignin (which is a cross-linked polymer of phenols, a component of biomass) is converted into graphitic porous carbon using a two-step conversion. Lignin is first carbonized in water at 300 °C and 1500 psi to produce biochar, which is then graphitized using a metal nitrate catalyst at 900–1100 °C in an inert gas at 15 psi. Graphitization effectiveness of three different catalystsiron, cobalt, and manganese nitratesis examined. The product is analyzed for morphology, thermal stability, surface properties, and electrical conductivity. Both temperature and catalyst type influenced the degree of graphitization. A good quality graphitic carbon was obtained using catalysis by Mn­(NO3)2 at 900 °C and Co­(NO3)2 at 1100 °C.

Lignin-derived heteroatom-doped porous carbons for supercapacitor and CO2 capture applications

“…Recently, significant research efforts have been directed toward converting lignin into valuable added materials, which are featuring a variety of potential applications. Current applications of lignin in concrete mixtures, porous carbons, animal feed pellets, road‐side dust control, dispersants, and wetting/binding agents have been well established . However, due to large unused supply of lignin, its transformation to new materials with viable applications is highly desirable.…”

“…Current applications of lignin in concrete mixtures, porous carbons, animal feed pellets, road-side dust control, dispersants, and wetting/binding agents have been well established. [21][22][23][24] However, due to large unused supply of lignin, its transformation to new materials with viable applications is highly desirable.…”

Fabrication of graphitic carbon spheres and their application in Al2O3‐SiC‐C refractory castables

“…So far, considerable efforts have been made to prepare graphitic carbon using Fe, Co, or Ni as a catalyst. It has been found that these catalysts are effective in enhancing graphitization of amorphous carbon at a reduced temperature . For instance, mesoporous graphitic carbon could be prepared at 1073 K using microcrystalline cellulose spheres loaded with iron salts as starting materials, in which case Fe NPs acted as the catalyst promoting the transformation from amorphous carbon to graphitic carbon.…”

Macroporous Carbon Supported Zerovalent Iron for Remediation of Trichloroethylene

“…The intensity ratio I D /I G between the D and G band has been widely used as a measure of defects in graphite-based materials. 31 The overtone of the D band around 2700 cm −1 (2D or G′) exhibits a strong intensity in highly ordered graphitic material. Figure 3 shows the Raman spectra of two graphite standards, lignin control biochar, and BC-ZVI produced from feedstock with different lignin/magnetite ratios.…”