Department of Inorganic Chemistry, Analytical Chemistry and Electrochemistry RCH1

Project team

1. Hubert Knap, Chemical Technology (team leader)
   
2. Wiktoria Krok, Biotechnology
3. Przemysław Niedbała, Chemstry
4. Natalia Golczuk, Mining and Geology
5. Wioletta Klimek, Chemstry
6. Maciej Smółka, Chemstry

Supervisors

1. prof. dr hab. eng. Marian Turek
2. dr hab. eng. Hanna Barchańska, prof. PŚ
3. msc. eng. Marianna Kostina-Bednarz

Description:

Tap water has a very high hardness in Gliwice (and not only), amounting to approx. 350 mg/l CaCO₃. This value is within the range specified by the Polish standard (60-500) but is far too high for some applications (e.g., for making tea, coffee the hardness should not exceed 175 mg/l CaCO₃). Few of the commercially available jug filters reduce hardness, but their ability to soften water is limited to about 7-10 days of use. Available systems, equipped with a reverse osmosis module, soften the water too much and it is necessary to increase the hardness, most often not very effectively.

We intend to test nanofiltration, instead of reverse osmosis, for softening tap water, using the original module, allowing to adjust the degree of softening, in order to achieve the desired, or according to the user's preferences, hardness value. In addition, we intend to test the effectiveness of removing 3 selected organic substances that (potentially) may be present in tap water.

Goals:

Familiarizing project participants with modern water softening methods and analytical methods for controlling its quality Learning about the comprehensive approach to scientific work: from design, through implementation to the presentation of result  Project participants acquire the ability to work in an interdisciplinary team: cooperation, division of duties and responsibilities, settlement of tasks, exchange of experiences, discussion of results, description of results Establishing international cooperation through the participation, as a consultant, of Prof. Alexandros Stefanakis from the Technical University of Crete Promoting the Silesian University of Technology among high school students through workshops conducted by Project participants.

Implementation methods:

pre-filtration (20 µm - carbon block filter - 5 µm), pre-filtration + nanofiltration (2 different membranes at the same time, several membrane combinations, different permeate yield), pre-filtration + reverse osmosis, filtration in a jug filter, filtrate analysis: determination of the content of . org., hardness (Ca2+, Mg2+), Cl-, HCO3-, SO42-. The effectiveness of removing PFASs from water using the mentioned techniques will be tested using model samples: tap water enriched with these substances.

Expected results:

Reduction of water hardness from approximately 350 mg/l CaCO3 to 60-175 mg/l CaCO3 by nanofiltration, with the possibility of adjusting the degree of water softening. Verification of compliance of water hardness obtained in the reverse osmosis-mineralizer system with the requirements of PN. Verification of the water softening effectiveness of jug filters. Determination of the efficiency of removing organic substances in all mentioned solutions.

Milestones:

Station preparation: pre-filtration + nanofiltration; Station preparation: pre-filtration + reverse osmosis; development of a methodology using liquid chromatography combined with a tandem mass spectrometer (LC-MS/MS) for the determination of PFOA, PFOS and PFBS in drinking water.