Preparation of 2D carbon ribbon/Al2O3 and nitrogen-doped carbon ribbon/Al2O3 by using MOFs as precursors for removing high-fluoride water
Lei Huang, Zhihui Yang, LÜ-ji YAN, Sikpaam Issaka Alhassan, Haiyin Gang, Ting Wang, Haiying Wang
Abstract
2D carbon ribbon/Al2O3 was synthesized with two-dimensional metal organic frameworks 2D-MOFs as precursors using the solvothermal and calcination methods. Batch experiments of adsorption parameters such as pH, liquid/solid ratio, adsorption kinetics, adsorption thermodynamics, and anions competitions were investigated to understand the adsorptive behavior of fluoride on carbon ribbon/Al2O3 and nitrogen-doped carbon ribbon/Al2O3. The adsorption of fluoride on carbon ribbon/Al2O3 could be described as the chemical and multilayer adsorption, while the adsorption of fluoride on nitrogen-doped carbon ribbon/Al2O3 followed the chemical and monolayer adsorption phenomenon. The fluoride on nitrogen-doped carbon ribbon/Al2O3 had a much faster adsorption rate of 3.1×10−7 m/s than carbon ribbon/Al2O3, which was 1.2×10−7 m/s. The nitrogen-doping on carbon ribbon enhances structural defects and improves the adsorption performance of fluoride. Also, the diacetylene linkages (—C≡C—) and pyridinic-N were studied to understand their influences on removing fluoride. The result indicates that carbon ribbon and nitrogen-doped ribbon could serve as good adsorbents for removing fluoride.