Removal of rhodamine B in wastewater from the textile industry using geopolymeric material

In this work a geopolymeric material was synthesized by alkaline activation of calcined coal gangue at 700 °C using a solution 1:9 of NaOH:Na₂SiO₃, as a sorbent to remove rhodamine B from aqueous solutions. X-ray diffraction, fourier-transform infrared spectroscopy and scanning electron microscopy were used to characterize the material structurally and morphologically; removal efficiency and rhodamine B sorption capacity were evaluated by using ultraviolet-visible spectrophotometry. Sorption tests were performed to evaluate the effect of the dose of geopolymeric material and the contact time of this material with rhodamine B solution in a range from 0.5 to 30 hours, interval in which the best sorption was observed. Removal efficiencies and sorption capacity to 80.4% and 1.035 mg/g respectively were found, these values show the usefulness of the material for the removal of rhodamine B in aqueous solution, making it an interesting alternative for water decontamination and object of study for future works. Removal efficiency increased by increasing geopolymer dosage and contact time.