Insight into the mechanism of carbon structure evolution of blended coal coking in the colloidal layer stage（DS）

The X-ray excitation source employed was Al Kα radiation (with hv = 1486.6 eV), and the X-ray beam spot was 400 μm. The excitation power was 150 W, and the X-ray beam spot was 500 μm. The binding energy was calibrated using C1s (284.8 eV).The crystalline structure of the samples was characterized using X-ray diffraction (XRD, Kuraray Co., Ltd., Japan) with a copper target radiation wavelength λ = 0.15405 nm, tube voltage 40 kV, current 100 mA, scanning range 2θ = 10°-90°, scanning speed ω = 3(°)/min and instrument step size 0.02°, Ds= 1°, Ss = 1°.Raman spectroscopy was primarily used to investigate the crystal and molecular structures of coal samples.

Raman analysis of a coal coke sample was performed using a Raman microscope (HORIBA Jobin Yvon S.A.S., France) equipped with a single-crystal silicon substrate. The measurement parameters were as follows: laser wavelength of 532 nm, laser power of 5 mW, spectral resolution of 1.5 cm⁻¹, integration time of 1 s, accumulation count of 10, and a scanning range of 100-4000 cm⁻¹.The data processing procedure is as follows: XRD data were subjected to peak deconvolution and fitting of characteristic peaks.

Raman spectra were baseline-corrected and smoothed, followed by peak deconvolution to obtain the peak positions, full width at half maximum (FWHM), and relative intensities for each vibrational mode. FTIR spectra were corrected for atmospheric background and baseline drift, then used to identify the vibrational modes corresponding to each absorption peak. XPS data were analyzed through peak deconvolution and combined with standard binding energy values to determine the chemical states and relative concentrations of each element.

TG data were processed via mass differentiation to generate DTG curves, which were used to determine the onset temperature, peak decomposition temperature, and corresponding mass loss rate for each decomposition stage.The data collection experiment was completed between October 2024 and January 2026. All data were collected through repeated measurements to ensure reliability.