REMOVAL OF CAFFEINE FROM WATER SOURCES USING ALGINATE/CARBON NANOTUBES BEADS

ANGIE E. ORDUZ; NATALIA GONZALEZ; CAROLINA ACEBAL; GRACIELA ZANINI

Wuhan-Modalidad Virtual

Conferencia; The 11th International Conference on Interfaces Against Pollution (IAP2021); 2021

Huazhong Agricultural University (HZAU)

According to the United States Environmental Protection Agency (USEPA), emerging contaminantsare defined as chemical compounds that can enter the environment with human health impacts thatare still unknown1. Caffeine (CF) is a psychoactive substance widely consumed both, in naturallyoccurring products such as tea, coffee, cocoa, and in artificial products, such as energy drinks. It isalso used as active ingredient of pharmaceuticals of massive used. The synthesis of new materialsfor CF adsorption/desorption is of great interest for its removal from water sources. There are somereports about the use of carbonaceous solid materials in combination with the biopolymer alginate inpollutant removal studies2, but its application in columns is scarce. In this sense, the present workproposes the synthesis and characterization of alginate/carbon nanotubes (AB/NTCs) compositebeads and the implementation of these materials in an adsorption/desorption minicolumn for theremoval of CF.For the synthesis of the AB/NTCs, a suspension was prepared by dispersing the NTCs in 1% w/vdeionized water using ultrasound for 2 h. At the same time, a solution containing 1% w/v alginate indeionized water was prepared and kept under constant stirring for 2 h. After homogenization of thealginate, the NTCs suspension was added. The beads were formed in a 0.1 M calcium chloridesolution. The beads were characterized by scanning electron microscopy, digital photography, andinfrared spectroscopy. A simple automated system was designed to carry out the adsorption anddesorption of CF. For this, beads were packed in a minicolumn (3.0 x 0.5 cm i.d.). A 1 mg L-1 solutionof CF was passed through the minicolumn at a flow rate of 0.50 mL min-1, and then acetonitrile wasused to perform the desorption. Quantification of CF was performed by UV-Vis. These conditionsindicate that it is possible to use the AB/NTCs composite packed in a minicolumn as a model for CFretention, quantification, and subsequent desorption of the sample to recover the original material.References[1] K. Vargas-Berrones, L. Bernal-Jácome, L. Díaz de León-Martínez, R. Flores-Ramírez. Sci. TotalEnviron., 726 (2020), p. 138493.[2] H.B. Quesada, T.P. de Araújo, D.T. Vareschini, M.A.S.D. de Barros, R.G. Gomes, R.Bergamasco,Int. J. Biol. Macromol. 164 (2020) 2535?2549.