چكيده به لاتين
Cobalt-aluminum layered double hydroxide (Co-Al-LDH) was successfully prepared by mechanochemical and mechano-hydrothermal methods. It was synthesized in a mortar by manually grinding the hydrated cobalt and aluminum nitrate salts with sodium hydroxide, however a mechano–hydrothermal method involved subsequent hydrothermal treatment. The powder XRD patterns of the sample prepared in the mortar showed all the characteristics of a layered structure but with a lower crystallinity. However, these results indicate that the hydrothermal treatment has led to a small but observable decrease in the interlayer spacing. The study also revealed that the properties of the synthesized LDH is comparable to that obtained from standard methods such as co-precipitation method, but with time, solvent and energy saving.
The as-prepared Co-Al-LDH exhibited a high adsorption activity to the methyl orange dye, metronidazol and tetracycline. Batch adsorption experiments were carried out at room temperature under various conditions such as contact time, adsorbate mass and pollutant concentration. The results of isotherm studies showed that adsorption of dye onto LDH fits to the Langmuire equation with sorption capacity of 657.12mg/g, although the removal of tetracycline and metronidazol followed the Sips isotherm model with maximum sorption capacity of 119.90 and 180 mg/g respectively. Due to the excellent removal capacity of methyl orange and tetracycline and metronidazol, the Co-Al-LDH could be a promising adsorbent for wastewater treatment.
Keywords: Layered Double Hydroxide, Mechanochemical, Mechano-hydrothermal, Absorption, Isotherm
