Magnetic nanocomposites as photocatalyts for Carbamazepine degradation

FRANCISCA APARICIO; CARLOS, LUCIANO; MAGNACCA, GIULIANA; DANIEL O. MARTIRE

Congreso; XIII Encuentro Latinoamericano de Fotoquímica y Fotobiología; 2017

Generally, nanostructured copper and ironbimetals possess unique photocatalytic and magnetic properties in, forinstance, environmental remediation. In particular, the nanosize copper andiron bimetal photocatalysts encapsulated in a robust carbon-shell can be apromising option [1]. We have prepared here different types of magneticmaterials using bio-based substances (BBS) obtained from composted urbanbiowaste [2] to complex Fe+3/M+2 ions. The complexes werethen subjected to thermal treatment under nitrogen atmosphere to developmagnetic phases. By varying the temperature of the heating treatment (400, 600and 800ºC), and the M2+ ion (Fe2+, Cu2+, Co2+,Ni2+), different materials were obtained. After a fullcharacterization they were used to photodegrade Carbamazepine (CBZ), anantiepileptic drug commonly found in natural waters [3]. In a typicalexperiment, 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-3500reactor equipped with 8 lamps with a maximum emission centered at 300 nm. Theremnant concentration of CBZ at different irradiation times was monitored byHPLC after magnetic separation of the nanoparticles. We found that for theFe/Cu materials the amount of CBZ photodegraded after six hours of irradiation wasstrongly dependent on the temperature reached during the heating treatment forthe synthesis of the nanomaterial. The CBZ photodegradation (ca. 80%) was thehighest for the samples treated at 600ºC, whereas it was only 40% for thematerial treated at 400ºC. Comparison of data with the series of nanocatalystsobtained using different M2+ ions and the thermal treatment at 600ºCshowed that the highest percentage of CBZ degradation (ca.90% after 3h) wasobtained for the material made  from Fe2+and Fe3+, whereas in the other cases only ca. of 80% degradation wasachieved after 5h. These differences are interpreted in terms of the structureand crystalline phases of the materials.