ORGANIC DYES ADSORPTION ON CARBON ADSORBENTS DERIVED FROM WASTE COTTON AND COTTON/POLYESTER YARN

Abstract

In an attempt to reuse fibrous textile waste, and at the same time to reduce its quantity, waste cotton-based yarn was used as a cheap and sustainable precursor for carbon adsorbents production. Cotton and cotton/polyester yarn samples were carbonized using hydrothermal and classical carbonization and activated using KOH as activating agent. Nitrogen adsorption-desorption isotherms, scanning electron microscopy, Fourier transform infrared spectroscopy, and Boehm titration methods were used to analyze the structural and surface properties of obtained carbon samples. The adsorption properties of cotton-based carbon materials were tested through the adsorption of selected organic dyes from water. The influence of contact time, initial concentration, and pH value of adsorbate solution on adsorption was examined and experimental data were processed by theoretical models. It was found that the adsorption properties of carbonized samples were negatively affected by the presence of a polyester component in the precursor structure. Nevertheless, the cotton-based carbon adsorbents obtained by carbonization, and subsequent activation proved to be highly efficient adsorbents for organic dye removal from water.

U cilju iskorišćenja vlaknastog tekstilnog otpada, kao i smanjenja njegove količine, otpadna prediva na bazi pamuka su korišćena kao jeftina sirovina za proizvodnju ugljeničnih materijala. Pamučno predivo, kao i predivo mešavine pamuka i poliestra, karbonizovani su primenom klasične ili hidrotermalne karbonizacije, i naknadno aktivirani u prisustvu KOH kao aktivirajućeg agensa. Strukturne i površinske karakteristike dobijenih ugljeničnih materijala ispitane su analizom adsorpciono-desorpcionih izotermi azota i rezultata Bemovih titracija, kao i skenirajućom elektronskom mikroskopijom i infracrvenom spektroskopijom sa Furijeovom transformacijom. Adsorpcija odabranih organskih boja iz vodenih rastvora je korišćenja za ispitivanje adsorpcionih karakteristika, a ispitan je i uticaj vremena kontakta, početne koncentracije i pH vrednosti rastvora adsorbata na adsorpcione kapacitete ugljeničnih adsorbenata. Pokazano je da prisustvo poliestarske komponente u strukturi prekursora ima negativan uticaj na adsorpcione karakteristike materijala dobijenih samo karbonizacijom. S druge strane, svi uzorci ugljeničnih materijala dobijeni karbonizacijom pređa na bazi pamuka i naknadnom aktivacijom pokazuju visoku efikasnost u uklanjanju boja iz vode.