Mechanical and microstructural characterization of geopolymers synthesized from FCC waste catalyst and silica fume

A FCC waste catalyst-based geopolymer was synthesized from FCC waste catalyst and silica fume, which were used as the main silicon-aluminum raw material and correction material, respectively. Meanwhile, NaOH and water glass composite were used as alkaline activator in the preparation process. Herein, the effects of silicon correction materials, alkaline activator modulus, and silica fume content on the compressive strength performance of prepared geopolymers were discussed. The microstructure was comprehensively analyzed by X-ray diffraction, fourier infrared spectroscopy, nuclear magnetic resonance spectroscopy and scanning electron microscope. The results showed that the prepared geopolymer has good early property when the silica fume content is 50% and the water glass modulus is 1.2. The 3d compressive strength of the obtained sample reaches 23.77 MPa. Microstructure and geopolymerization process analysis indicate that the FCC waste catalyst and silica fume have a good synergistic effect, which confirms the feasibility of preparing the geopolymer by using these industrial waste materials.