PRODUCTION OF CELLULOSE-GRAPHENE OXIDE (CO-GO) NANOCOMPOSITES FOR THE EXTRACTION OF NANOPLASTICS FROM FRESH WATER

Water is a vital component of environment and an essential part of living beings, but the quality of water has been a problem for humans since the beginning of time. Pollution of water systems is mainly the result of industrialization, agriculture and domestic, transport and chemical activities in the environment [1-3]. As urbanization increased, so did the need for alternative, non-renewable resources for domestic and industrial applications, leading to the emergence of the polymer industry. However, the advantage of plastics in terms of easy accessibility, low prices and multiple applications in every household and in almost all walks of life also comes at the cost of overuse and improper disposal in the environment, which leads to the destruction of the polymer structure at the micro and nanoscale, resulting in the release of nanoplastics (NPs) in the environment. These plastic particles are detected in the environment [4] and in the cells of various living organisms [5], raising concerns about potential toxicity in living cells. Therefore, the development of novel materials that are ecologically safe to remove pollutants from freshwater is one of the most important and growing concerns of the 21st century. Various techniques are already used to remove pollutants from freshwater, but adsorption has proven to be a useful technique for water treatment with low cost and good efficacy. Cellulose (CO) is an inexpensive, biodegradable, abundant, non-toxic material that has a high adsorption capacity due to the hydroxyl groups (-OH) present on its surface that form adsorption sites. In addition, graphene oxide (GO), which has various functional groups such as hydroxyl, carbonyl, carboxyl, and epoxy groups, is a good adsorbent. In this study, a synthesized cellulose-graphene oxide (CO-GO) nanocomposite was used to remove polyethylene (PE) and polystyrene (PS) NPs prepared by nanoprecipitation. GO was prepared by a modified Hummer‘s method. The CO-GO nanocomposite was prepared by mixing cellulose and GO solutions with the addition of glutaraldehyde as a crosslinking agent. The PE-NPs and PS-NPs were prepared by separately dissolving polyethylene and polystyrene in trifluoroacetic acid. Both solutions were then mixed with polyvinyl alcohol and stirred continuously until the NPs had formed and stabilized. The solution was centrifuged to separate the NPs and dried. The CO-GO nanocomposite was used in adsorption experiments with PE-NPs and PS-NPs. TEM, SEM, FT-IR, Raman spectroscopy, and XRD methods were used to characterize the CO-GO nanocomposites. The characterization results show that the nanocomposites were synthesized and pretested for the adsorption of nanoplastics. TEM, SEM, FT-IR, Raman spectroscopy and XRD methods were used to estimate the changes that occurred during the adsorption process.