Application of membrane filtration and adsorption processes in the removal of micropollutants released from microplastics

Microplastics, derived from the decomposition of plastics, can be identified in almost any type of surface water. Various pollutants, which are often toxic and hardly biodegradable, can leach from these particles. For this reason, it is important to know the possibilities of their effective removal from water. The tests carried out were aimed at determining the effectiveness of removing the tested substances from water - isophorone, dimethyl phthalate, and 4-tert-octylphenol in membrane processes using the following membranes: NF270, BX, V5, as well as adsorption on powdered activated carbon. The tests using membrane techniques consisted of passing the feed (water solution of the tested pollutants) under high pressure through the membrane, which was collected as permeate after filtration. The membrane was conditioned before testing. During the test with the use of activated carbon, its sorption properties were tested at varying doses of activated carbon in the samples (and constant concentrations of pollutants in water) and at different times of contact with pollution (at constant doses of activated carbon and constant concentration of pollutants in water). Studies using ultra-and nanofiltration membranes have shown that the type of membrane had a significant impact on the effectiveness of the pollutant removal process. The highest efficiency was obtained using a nanofiltration membrane for all tested substances. The conducted adsorption tests showed that the concentration of the tested pollutants decreases with the increase in the dose of activated carbon and the extension of the contact time of the pollutant with the sorbent. Comparing the effectiveness of the processes used to remove the tested pollutants leached from microplastics, it can be concluded that greater efficiency was obtained in the adsorption process on activated carbon.