Dithiocarbamate-modified cellulose resins: A novel adsorbent for selective removal of arsenite from aqueous media.

We synthesized three new dithiocarbamate (DTC)-modified cellulose biomaterials (DMC-1, DMC-2, and DMC-4) to investigate their adsorption capabilities as mitigators of arsenite (As) in aqueous media. The main novelty of the adsorbents was that, among two inorganic species of arsenic, arsenite and arsenate (As), DMCs were highly selective to As in the pH range 2-7. The surface areas of the adsorbents were unified by supporting the DMCs on silica gel (designated SSDMC-1, SSDMC-2, and SSDMC-4, respectively) to investigate the effect of the length of the alkyl chains connecting cellulose and DTC groups on As adsorption. The Langmuir model showed a good regression coefficient (R > 0.96), and the isotherm results revealed that longer chains might enhance the As capture ability. The adsorbents were also capable of removing various heavy metals, and the coexisting ions, Fe, Mn, Pb, and Zn, had no significant impact on the removal of As by the DMCs. Moreover, DMC-2 could remove 98.4 ± 0.1% of As from artificially contaminated river water.