A New Surface Decorated Geopolymer Matrix: Insights and Modeling into Comprehensive Sorptive Decolorization Applications

Water contamination caused by synthetic dyes is a severe environmental issue that requires immediate action. Research on treatment and resource conservation technologies is expanding rapidly. One interesting option could be to use environmentally friendly sorbent composites. To efficiently remediate dye-contaminated waters, we manufactured an innovative composite sorbent called MGEOP@MnO2 by applying metal oxide particles to the surface of a metakaolin-based geopolymer. Both batch and continuous mode sorption studies verified that MGEOP@MnO2 was highly effective at removing the targeted dye. BET, XRD, SEM-EDX, and FTIR techniques were employed to comprehensively evaluate the morphological and structural features of the suggested sorbent, as well as to disclose the possibility of dye interaction. The Box–Behnken design (BBD) and response surface methodology (RSM) were utilized to optimize the process by evaluating the interactive impacts of crucial parameters, including contact time, sorbent amount, initial pH, flow rate, and solution volume. While the D–R, Langmuir, and Freundlich isotherms have significant coefficients of determination and match the experimental data, the pseudo-second-order model dominates the sorption kinetics. After optimizing the settings using the BBD design, the decolorization efficiencies of Bismarck Brown Y (BBY) in batch and continuous systems were 96.71% and 96.14%, respectively. Furthermore, the removal efficiencies of over 90% achieved by MGEOP@MnO2 in these systems in the real wastewater application test were remarkable. The results suggest that MGEOP@MnO2 could be a viable solution to the water pollution problem caused by dye contamination.