Recycling of light-emitting diode waste quartz sand as a pozzolanic material

LED waste quartz sand (LEDWS), which is a prominent byproduct of the LED manufacturing process, may contaminate the environment because it comprises numerous nanoparticles of SiO2, Al2O3, and SiC, which are hazardous ingredients that are harmful to the environment and human health when disposed of improperly. Therefore, this study investigated the pozzolanic reaction behavior of these industrial byproducts to obtain a valuable processing method for LEDWS in cement. The results showed that with increased curing time, the strength of the pastes that incorporated 10% LEDWS approached that of ordinary Portland cement. A stretching broad band was centered at 1074–1081 cm−1 from chemically bound H2O in the hydrated calcium silicate (C–S–H). Thus, the correlation between the hydration degree of the paste that incorporated LEDWS and compressive strength evolution is crucial. The results implied that LEDWS can be used as a partial replacement source for cement applications; thus, LEDWS can be used as pozzolanic material.