Synthesis of Inorganic Polymeric Materials from Industrial Solid Waste

The present paper highlights the high strength of inorganic polymer (geopolymer) prepared from industrial solid waste. Fly ash (industrial solid waste) was used as the starting raw materials and a solution of sodium hydroxide solutions and sodium silicate solutions were used as alkaline activators. The concentration of the sodium hydroxide solutions is maintained at 6, 8, 10, 12, 14, and 16 molars, and the ratio of sodium hydroxide to sodium silicate solution is maintained at 1. The alkaline solutions were mixed with fly ash powder, followed by casting at room temperature. The as cast geopolymer samples were artificially cured at 60 degrees C for a fixed time of 50 h. Mechanical testing of cured geopolymer specimens was carried out and the maximum value of compressive strength (73 MPa), flexural strength (14.1 MPa) and Vickers hardness (153.33 HV) were achieved. The achieved data were confirmed by characterizing the specimens by FESEM-EDS, TEM and FTIR techniques as well. Further, the water absorption test and the durability test of geopolymer specimens under 5% HNO3, H2SO4 , HCl, and NaCl solutions were done.