Sonochemically Synthesized Mesoporous Pyrophanite- MnTiO3/TiO2 Nanoparticles: Adsorbent for Removal of Commercial Malachite Green Dye

Malachite Green (MG) dye belongs to the triphenylmethane class and exhibits a noxious impact on the living being. Thus, it’s being immensely important to remove it from the environment matrix. Herein, the sonochemical synthesized adsorbent material -pyrophanite-MnTiO3/TiO2 NanoParticles (NPs) was utilized to expel the commercial Malachite Green (MG) dye from the solution. The adsorption efficacy data indicate the maximum removal of MG (90.2%) is obtained for the NPs calcinated at 1000 °C (MT1). The optimized adsorption material (MT1) is characterized by using different techniques including XRD, FE-SEM, EDX, FTIR, BJH, and BET. The XRD analysis indicates the formation of divergent phases viz. rutile TiO2 and MnTiO3. The FE-SEM indicates the formation of a nano-rod-like structure. The average size and percentage of void space of MT1 NPs are evaluated by using IMAGE J software. The hysteric loops obtain from BET and BJH plots reveal the existence of type H3 hysteresis indicating the MT1 NPs exhibit mesoporous structure. The surface area, pore volume, and pore size are 61.245 m2/g, 0.139 cm3/g, and 2.0178 nm respectively. The pH, dye concentration, and temperature of the solution are optimized for the removal of MG by using MT1 NPs. Further, the adsorption isotherms, kinetics studies, and intra-particle studies indicate that monolayered second-order diffusion occurs onto the surface of MT1 NPs. The adsorption process is endothermic, thermodynamically driven, and accompanied by an increase in entropy.