Removal of Water-Soluble Anoinic Dyes from Wastewaters by Using Dithiocarbamate Modified Starch-Coated Magnetic Nanoparticles

Natural polysaccharides are environmentally friendly materials for removing toxic pollutants from aqueous solutions, and attracted much attention. Among numerous polysaccharides, starch is an abundant, inexpensive, renewable and fully biodegradable natural raw material. However, its application in dyes removal is limited due to its low capacity and stability. To circumvent these problems, modified starches has been synthesized and applied as adsorbent for anionic dyes. We showed that the Fe3O4 magnetic nanoparticles coated with dithiocarbamate-modified starch (DTCS-MNPs) is an efficient adsorbent for the removal of water-soluble anionic dyes from wastewaters. It is found that the capacity of DTCS-MNPs for each dye is pH dependent, and the adsorption is governed by electrostatic attractions. The desorption data shows that the removal percent of dye from the dye loaded DTCS-MNP is over 80% in 0,25 mol/l Na2SO4 solutions at 25 ºC.