2024 : 4 : 14
Amir Azizi

Amir Azizi

Academic rank: Assistant Professor
ORCID: https://orcid.org/0000-0003-2741-6797
Education: PhD.
ScopusId: 56318653900
Faculty: Science
Address: Arak University


The role of counter-anions in photocatalytic reduction of Ni(II) with a trace amount of titania nanoparticles
Counter anion · Photocatalytic reduction · Nickel ion · Kinetic study · Energy consumption
Journal Journal of the Iranian Chemical Society
Researchers javad Saien ، Amir Azizi ، fatemeh ghamari


The reduction of Ni(II) ion, originated from nitrate or sulfate salts, was investigated based on photogenerated electrons in UV-irradiated TiO2 aqueous suspensions. Design of experiments, modeling, and process optimization were performed using central composite design of response surface methodology. Influence of pH, temperature, and nickel concentration was investigated based on percentage of reduction efficiency (RE). Under operating conditions of pH = 9.3, T = 40 °C, [Ni(II)]o = 5 mg L−1, [TiO2] = 100 mg L−1 and after 90 min treatments, 64.8 and 76.1 % RE were achieved for nitrate and sulfate counteranions, respectively. The higher efficiency obtained with sulfate anion was attributed to the more ionic strength and its interaction with titania nanoparticles. Rate of Ni(II) ions reduction, originated from both of the nickel salts, obeys pseudo-first-order kinetic model. As a relevant criterion, the electrical energy consumption and other criteria were evaluated and were compared with other previously reported processes.