TiO2-assisted Photocatalytic Degradation of Vitamin B12 in Aqueous Solution:Influencing Factors, Kinetics, and Reaction Investigations

Abstract

The photodegradation (λ＝365 nm) of the biomolecule vitamin B 12 , catalyzed by the photocatalyst TiO 2 nanoparticles (NPs), has been investigated in aqueous suspension. The photodegradation process of vitamin B 12 has been monitored by means of electronic absorption (Abs), Fourier-transform infrared (FT-IR), and resonance Raman (RR) spectroscopies, respectively. The results show that only under UV illumination in the presence of TiO 2 is there effective degradation, and the photocatalytic degradation of vitamin B 12 is strongly influenced by the amount of TiO 2 NPs, the pH, and the initial concentration of vitamin B 12 . The photocatalytic reaction kinetics of vitamin B 12 conforms to a Langmuir-Hinshelwood isotherm model. Changes involving the three structural units of the carbon-metal bond C-Co, the organic corrin macrocycle combined with the benzimidazole nucleotide, and the inorganic CN in the vitamin B 12 molecule during the photocatalytic degradation are also discussed.

Ag‐doped TiO2 enhanced photocatalytic oxidation of 1,2‐cyclohexanediol

“…Continuing our interest on PCO of cyclic and acyclic alcohols, as well as other interests on PCO of biomolecules, the present article embraces PCO of 1,2‐cyclohexanediol ( 1 ). Cyclohexane moiety represents the base structure of many biomolecules such as sterols and estrogens hormones (estriol).…”