Hydrothermal Synthesis and Crystal Structure of a New Organic-Inorganic Magnesium Complex, Designed to Produce Efficient Sorbent for the Removal of the Antibiotic Tetracycline

Abstract

The present study reports the synthesis of a new organic-inorganic hybrid complex formulated as [Mg(phen)(H 2 O) 4 ]bdc. phen. H 2 O ( 1 ) where phen = 1, 10-phenanthroline and bdc 2- = isophthalato by hydrothermal method at 110oC for 3 days. The structure of compound 1 was characterized by elemental analysis, thermal gravimetric analysis (TGA), differential thermal analysis (DTA) and single-crystal X-ray diffraction (SCXRD). The results of SCXRD analysis revealed a monoclinic structure with space group P 2 1 / n of the expected complex. For the first time, effective sorbent of MgO/SiO 2 was prepared by thermolysis [Mg(phen)(H 2 O) 4 ]bdc. phen. H 2 O/SiO 2 as a new precursor. The obtained sorbent was characterized by Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett –Teller (BET) specific surface area. The synthesized catalyst was applied for tetracycline (TC) removal from aqueous solution in order to assess its potential as a sorbent. At 25oC with no NaCl, the synthetic catalyst shows the maximum removal of about 85.2%. Also, the results show that the TC removal is highly pH-dependent and reached a maximum value at pH of 6. The influence of the TC dosage and the solution temperature on the removal process were also assessed. From the results it can be concluded that the synthetic sorbent has acceptable activity in the removal of TC from contaminated waters as well as centrifugation separation, advantage in use and acceptable recyclability.