Adsorption of industrial dye onto a zirconium metal-organic framework: synthesis, characterization, kinetics, thermodynamics, and DFT calculations

Pollution that arises from textile industries is a serious environmental issue, and successful purifying has thus far proven to be difficult. In this study, environmentally safe Zr-metal-organic frameworks (Zr-MOF) were used to develop a strategy for removing Methylene Blue (MB) from water contaminants. The elimination of MB in wastewater samples by Zr-MOF showed good adsorption capability. SEM, FT-IR, XRD, XPS, and surface area confirmed that Zr-MOF has a large area of 1498 m2/g besides a microporous material having a pore diameter of 1.2 nanometers. The pH of the starting solution, amount of adsorbent used, contact period, and temperature were investigated. The pHPZC of Zr-MOF was 7.5. The adsorption of MB on Zr-MOF adsorbents was determined as sideways interrelations by a monolayer model based on the real gas law (MMRG) and a monolayer model based on the ideal gas law (MMIG). Zr-MOF has good capability for removing MB (1.58 mmol.g−1) and after numerous cycles, this performance remained; up to the sixth cycle, the adsorbent had recyclability of >91.6%. Adsorption experiments demonstrated that adsorption kinetics matched a pseudo-second-order model and the Langmuir equation. Activation energy was 15.87 kJ/mol. The microporous Zr-MOF adsorbent proved to be simple and effective for water purification.