Gulf of Finland Science Days “Facing our Common Future” was held in Helsinki, in the House of Estates, on 13-14 November 2019.

Daria Navolotskaya (Saint Petersburg State University, Department of Analytical Chemistry) and Roman Nekrasov (Peter the Great St. Petersburg Polytechnic University, Higher School of Automation and Robotics ) participated in the conference with the subjects of the reports:

Daria Navolotskaya: OneDrop – A Novel Mobile Water Purification Plant: Possibilities for the GoF Water Treatment;

“OneDrop” is an interdisciplinary project aimed at the development of a novel mobile water purification plant. The project is
funded by “The South-East Finland – Russia CBC 2014-2020 Programme”. There are five partners involved in the project: Lappeenranta-Lahti University of Technology, Saint-Petersburg State University, Peter the Great Saint-Petersburg Polytechnic
University, NPK Omega and the Port of Lappeenranta. The main part of the mobile plant under development is the electrolysis unit producing ferrate (VI). Being a strong oxidizing agent, ferrate (VI) can be used for oxidizing emerging contaminants and toxins and for deactivating harmful micro-organisms in water treatment without generating hazardous by-products as opposed to chlorination and ozonation. That’s why ferrate (VI) is often termed as a “green chemical”. Moreover, the decomposition of ferrate (VI) produces Fe (III), which itself is an excellent coagulant for removal of metals and radionuclides from contaminated water. Ferrate technology can be used for the treatment of both drinking water and wastewater. By the moment we have already developed and tested a prototype of the electrolysis unit, as well as methods for determination of ferrate concentration. The removal efficiency of ferrate (VI) towards inorganic and organic water contaminants, including pharmaceuticals, was studied. Testing the proposed water purification technology on the water samples from the Gulf of Finland is planned.

Roman Nekrasov: Efficacy Estimation of Electron Irradiation and Sodium Ferrate Usage for Purification of Water Samples Contaminated with Diclofenac;

Nowadays there is observed rapid growth of the pharmaceutical industry in the World and traditional methods of water parameters control, such as Total Coliforms Amount and residual chlorine, is amplified with new problems in the face of DBPs. In waters of Saint Petersburg and the Leningrad region, this problem also appeared, e.g. with sodium diclofenac as an example. The goal of current research compares two methods of purification for Diclofenac-contaminated water: reagent based method with an oxidizer (sodium ferrate) and electron irradiation. As a result of the provided experiments, there were analyzed optical densities before and after treatment by both methods. The research revealed minimal doses for the maximal degree of purification, attained in current research = 46 % (for purification of the sample of 25 ml with sodium diclofenac concentration of 100 mg/L was required dose: 0,15 mg/L of sodium ferrate or irradiation by 1 MGy). Finally, the approbation of both methods could be considered as successful, but more objective results need in-depth study with model solution concentrations to be close to MRL levels.