title: Arsenic(III) sorption on nanostructured cerium incorporated manganese oxide (NCMO): a physical insight into the mechanistic pathway.
abstract: Arsenic(III) sorption was investigated with nanostructured cerium incorporated manganese oxide (NCMO). The pH between 6.0 and 8.0 was optimized for the arsenic(III) sorption. Kinetics and equilibrium data (pH=7.0±0.2, T=303±1.6 K, and I=0.01 M) of arsenic(III) sorption by NCMO described, respectively, the pseudo-second order and the Freundlich isotherm equations well. The sorption process was somewhat complicated in nature and divided into two different segments, initially very fast sorption followed by slow intraparticle diffusion process. Sorption reaction of arsenic(III) on NCMO was endothermic (ΔH°=+13.46 kJ mol(-1)) and spontaneous (ΔG°=-24.75 to -30.15 kJ mol(-1) at T=283-323 K), which took place with increasing entropy (ΔS°=+0.14 kJ mol(-1)K(-1)) at solid-liquid interface. Energy of arsenic(III) sorption estimated by analyzing the equilibrium data using the D-R isotherm model was 15.4 kJ mol(-1), indicating the ion-exchange type mechanism. Raman, FT-IR, pH effect, desorption, etc. studies indicated that arsenic(III) was oxidized to arsenic(V) during the sorption process.
authors.affiliation: Department of Chemistry, Presidency University, 86/1 College Street, Kolkata 700 073, India.
authors.forename: K
authors.initials: K
authors.lastname: Gupta
authors.forename: S
authors.initials: S
authors.lastname: Bhattacharya
authors.forename: D
authors.initials: D
authors.lastname: Nandi
authors.forename: A
authors.initials: A
authors.lastname: Dhar
authors.forename: A
authors.initials: A
authors.lastname: Maity
authors.forename: A
authors.initials: A
authors.lastname: Mukhopadhyay
authors.forename: D J
authors.initials: DJ
authors.lastname: Chattopadhyay
authors.forename: N R
authors.initials: NR
authors.lastname: Ray
authors.forename: P
authors.initials: P
authors.lastname: Sen
authors.forename: U C
authors.initials: UC
authors.lastname: Ghosh
mesh_terms: D000327:Adsorption; D001151:Arsenic / Q000737:chemistry*; D002563:Cerium / Q000737:chemistry*; D002627:Chemistry, Physical; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D017895:Manganese Compounds / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D002563:Cerium; C027424:manganese oxide; D001151:Arsenic