SYNTHESIS OF Ti02-BASED NANOMATERIALS AND THEIR APPLICATION IN ARSENIC REMOVAL FROM DRINKING WATER

Abstract

ABSTRACT Pure -riC)3 ( l nrn) and iron-doped Ti02, (65 nno ) nanoparticles synthesized via sol-gel process were used along Wilh (General Purpose Reagent (GPR) (325 for studies of Arsenic from drinking water. nanopatricles were in n anatase cystalline phase. Energy dispersive elenlental analysis indicated better percentage purity of lab synthesized nanoparticles as conopared to GPR Yellow orange color ol' doped 'l'iC)2 showed a red shift in absorption wavelength frono 387.5 nrn to around 435 run, thereby Inal<ing the doped species visible light responsive. Pure nanoparticles were successfully immobilized by generatinu titaniacoated sand ('ICS) singly ("ICS-I ) and doubly ("I T C-S-2) via the sol-gel process. [o see the ef'ftcts or different conditions on Arsenic adsorption, live systenus were used, viz., As(V) in Air-Light , As(lll) in Air-Light, Air-Sunlight, and Nitrogen-Dark conditions. Kinetics of adsorption föllosved pseudo-second order rate except for As(IlI)-Air-Light systeln which followed Elovich noodel. Adsorption of Arsenic on the adsorbents föllowed Freundlich and Langnn [lir Inodel. Iron-doped Ti02 showed higher affinity for Arsenic than pure 'l'iC)2 which in turn showed greater affinity than CiPR Similarly, 'FCS-2 showed higher Arsenic affinity than r [CS-I Removal of As(lll) '.vas higher in light and oxidizing conditions than in dark and anoxic conditions, pH dependence behavior, Point of Zero C'harge of the nanoadsorbents estiænated to be around 7. Arsenic adsorption decreased with increase in PI-I. In TCS column test, 98 0 0 of As(V) and As(lll) was reinoved with no leaching up to 1 500 and 1450 bed volumcs, respectively