Synthesis of g-C3N4@ZIF-8 nanomaterial and its use for rapid removal of alizarin red and ketoprofen from water via chemical catalysis

Abstract

The development of a new catalyst for highly efficient degradation of environmentally harmful pollutants is targeted. In this study, g-C₃N₄@ZIF-8 catalyst was produced to reduce both the widely used drug ketoprofen (KEP) and the harmful organic dye impurity alizarin red S (ARS) from aqueous solutions. ZIF-8 compound containing Zn metal from the MOF group and nanoparticles containing graphitic carbon nitride (g-C₃N₄) were synthesized by easy calcination method, and their structural and surface characterizations were completed. The synthesized g-C₃N₄@ZIF-8 was analyzed XRD, ATR-FTIR, XPS, BET, and SEM–EDX and then used as a catalyst for the catalytic degradation of ARS and KEP. Optimum parameters were determined by investigating the effects of catalyst amount, NaBH₄ concentration, contact time, and pH on the removal mechanism. Furthermore, g-C₃N₄@ZIF-8 demonstrated good stability and reusability in five experiments involving the degradation of KEP and ARS, and a metal leaching study showed that it did not leach a significant amount of zinc into the environment. Zero-order, pseudo-first-order, and second-order kinetic models were used to describe the removal of ARS and KEP. The pseudo-first-order model, with the R² value closest to 1, was found to be suitable, and the k value was calculated by plotting graphs showing the variation between ln[C_t/C₀] and time.