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Graphite demand is increasing rapidly due to the popularity of electric vehicles (EVs) and mobile devices. Lithium-ion batteries (LIBs) are the power source of EVs and mobile devices and the anodes of LIBs are mostly made of graphite, which is currently produced in an unsustainable and costly manner. For the first time, battery-grade biographite is produced from a renewable and sustainable precursor, biomass-derived pyrolysis oil, using iron as the graphitizing catalyst. Considering battery-grade graphite production at scale, pyrolysis oil offers several advantages as feedstock over biomass in terms of higher carbon density, low inorganics, easy handling, and low transportation cost. Catalytic graphitization of pyrolysis oil can be induced at low temperature (∼1100 °C). Herein, catalytic graphitization using iron powder was carried out under relatively moderate conditions (1500 °C) to reduce costs and environmental impact as compared to incumbent technologies. After graphitization, the residual catalyst was removed by refluxing the biographite + iron solid mixture with hydrochloric acid. The efficiency of iron removal was studied using the X-ray fluorescence (XRF) technique. The structural and morphological properties of biographites were assessed via X-ray diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HR-TEM). The in situ XRD experiments provided a mechanistic understanding of the iron-catalyzed graphitization process. In addition, the effect of pyrolysis oil aging on the biographite crystalline structure was elucidated. The optimal biographite sample demonstrated impressive electrochemical performance with a reversible capacity of 350 mA h g−1, an initial coulombic efficiency of 90.2%, and minimal capacity loss over 100 cycles when applied as an LIB anode, thereby making pyrolysis oil-derived biographite potentially competitive with commercially available battery-grade graphite. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) spectroscopy was used to predict the longitudinal tensile modulus, the longitudinal tensile strength, and the creosote content of wood from an out-of-service southern pine utility pole. Tensile samples were cut from the pole in the radial direction and near-infrared spectra were obtained before testing. Coefficients of determination [r.sup.2], of 0.80-0.86 were obtained between the NIR spectra predicted modulus and measured modulus. Coefficients of determination for strength were lower, 0.58-0.63. After tensile testing, the specimens were ground in a mill and spectra were obtained from the homogeneous ground samples. There was a slight decrease in the coefficients of determination using the ground samples, 0.76-0.82 for the modulus and 0.46-0.57 for the strength. Creosote content was difficult to predict with the NIR spectra of the whole sample, but coefficients of determination >0.9 were obtained with the ground samples. There was little difference in the results for spectra collected over the 350-2,500 nm range and those obtained with just looking at the 950-1,850 nm range. This suggests that it will be feasible to predict the mechanical properties of treated timber using lightweight, relatively inexpensive, portable instruments rather than larger, more expensive systems that cover the entire NIR range. DOI: 10.1061/(ASCE)0899-1561(2007)19:4(279) CE Database subject headings: Wood; Nondestructive tests; Elasticity; Measurement; Tensile strength.