Phenol Adsorption Performance of Nitrogen-Doped Porous Carbon Derived from Silicon Oxycarbide Ceramics

Mesoporous silicon oxycarbide (SiOC) ceramics were prepared by using the solvothermal method with vinyltriethoxysilane as precursor in hexamethylenetetramine solution, and N-doped porous carbon materials (SiOC-DC) were derived by selective etching with HF solution. SiOC ceramics prepared at 1200 degrees C exhibits the highest degree of graphitization, and the O/Si ratio in SiOC ceramics decreases as increase of the pyrolysis temperature. The phase separation generates limited SiC nanograins, and SiC nanowires is formed mainly by carbothermal reduction reaction. Besides the presence of mesopores, more micropores are generated in SiOC-DC when the pyrolysis temperature increases to 1400 degrees C. The N content of SiOC-DC increases as the elevation of pyrolysis temperature, and the N element exists mainly in the form of pyridinic N. As the adsorbent to remove phenol, the adsorption capacity of SiOC-DC increases not only with the elevation of pyrolysis temperature, but also with the increased initial concentration of phenol. SiOC-DC with the specific surface area of 1054.2 m2g-1, micropore volume of 0.48 cm3g-1 and N content of 3.5 wt% exhibits a good phenol adsorption performance, and the equilibrium adsorption capacity of HMTA-1400-HF is 72.3 mgg-1.