Equilibrium and kinetics study on removal of arsenate ions from aqueous solution by CTAB/TiO2and starch/CTAB/TiO2nanoparticles: a comparative study.
We present a comparative study on the efficacy of TiO2nanoparticles for arsenate ion removal after modification with CTAB (N-cetyl-N,N,N-trimethyl ammonium bromide) followed by coating with starch biopolymer. The prepared nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), thermogravimetry, scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDX). The removal efficiency was studied as a function of contact time, material dose and initial As(V) concentration. CTAB-modified TiO2showed the highest arsenate ion removal rate (∼99% from 400 μg/L). Starch-coated CTAB-modified TiO2was found to be best for regeneration. For a targeted solution of 400 μg/L, a material dose of 2 g/L was found to be sufficient to reduce the As(V) concentration below 10 μg/L. Equilibrium was established within 90 minutes of treatment. The sorption pattern followed a Langmuir monolayer pattern, and the maximum sorption capacity was found to be 1.024 mg/g and 1.423 mg/g after starch coating and after CTAB modification, respectively. The sorption mechanisms were governed by pseudo second order kinetics.
Department of Chemical Sciences, Tezpur University, Assam 784028, India E-mail: tkm@tezu.ernet.in.
Pankaj
P
Gogoi
Department of Chemical Sciences, Tezpur University, Assam 784028, India E-mail: tkm@tezu.ernet.in.
Debasish
D
Dutta
Department of Chemical Sciences, Tezpur University, Assam 784028, India E-mail: tkm@tezu.ernet.in.
Tarun Kr
TK
Maji
D001149:Arsenates / Q000737:chemistry*; D002593:Cetrimonium Compounds / Q000737:chemistry*; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry*; D013213:Starch / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D001149:Arsenates; D002593:Cetrimonium Compounds; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D013213:Starch; D014025:Titanium