Magnetic nanocomposites as photocatalyts for Carbamazepine degradation

FRANCISCA APARICIO; LUCIANO CARLOS; GIULIANA MAGNACCA; DANIEL O. MÁRTIRE

Villa Carlos Paz

Encuentro; XIII Encuentro Latinoamericano de Fotoquímica y Fotobiología; 2018

Generally, nanostructured copper and iron bimetals possess unique photocatalytic and magnetic properties in, for instance, environmental remediation. In particular, the nanosize copper and iron bimetal photocatalysts encapsulated in a robust carbon-shell can be a promising option [1].We have prepared here different types of magnetic materials using bio-based substances (BBS) obtained from composted urban biowaste [2] to complex Fe+3/M+2ions. The complexes were then subjected to thermal treatment under nitrogen atmosphere to develop magnetic phases. By varying the temperature of the heating treatment (400, 600 and 800ºC), and the M2+ ion (Fe2+, Cu2+, Co2+,Ni2+), different materials were obtained. After a full characterization they were used to photodegrade Carbamazepine (CBZ), an antiepileptic drug commonly found in natural waters [3]. In a typical experiment, 100 mL suspensions of 2 mg L-1 of CBZ and 0.625 g L -1of the particles were irradiated with constant stirring in a Rayonet RPR-3500 reactor equipped with 8 lamps with a maximum emission centered at 300 nm. The remnant concentration of CBZ at different irradiation times was monitored by HPLC after magnetic separation of the nanoparticles.We found that for the Fe/Cu materials the amount of CBZ photodegraded after six hours o irradiation was strongly dependent on the temperature reached during the heating treatment for the synthesis of the nanomaterial. The CBZ photodegradation (ca. 80%) was the highest for the samples treated at 600ºC, whereas it was only 40% for the material treated at 400ºC. Comparison of data with the series of nanocatalysts obtained using different M2+ ions and the thermal treatment at 600ºC showed that the highest percentage of CBZ degradation (ca.90% after 3h) was obtainedfor the material made from Fe2+and Fe3+, whereas in the other cases only ca. of 80% degradationwas achieved after 5h. These differences are interpreted in terms of the structure and crystalline phases of the materials.