Sustainable technology for production of lignocellulosic membranes for removal of anionic and cationic pollutants from water

[N. Knežević]

112 str.

Tehnološko inženjerstvo - Inženjerstvo zaštite životne sredine / Technological Engineering - Environmental Protection Engineering

Ova doktorska disertacija bavi se održivim tehnologijama za proizvodnju lignoceluloznih membrana namenjenih uklanjanju anjonskih i katjonskih zagađivača iz vode u cilju očuvanja životne sredine i poboljšanju kvaliteta života. Ispitivane su dve vrste funkcionalizovanih membranana na bazi celuloze. Prva membrana (TOPM) je dobijena je iz pamučnih lintersa oskidisanih sa 2,2,6,6- tetrametilpiperidin-1-oksil radikalom. Druga membrana je dobijena (HHH-UKM) katjonskom funkcionalizaijom otpadnih vlakana konoplje. Svi materijali su okaraketrisani primenom spektroskopskih, mikroskopskih i analitičkih tehnika. Adsorpciona svojstva membrana ispitana su u šaržnom i protočnom sistemu. Primenjene adsorpcione izoterme, opisale su interakciju između adsorbata i adsorbenta u ravnotežnom stanju ispitivanog sistema i potvrdile visoke adsorpcione kapacitete membrana za uklanjanje katjonskih i anjonskih zagađivača. Nakon višeciklične desorpcije, obe membrane su podvrgnute testovima biorazgradivosti. Dobijeni rezultati (70 dana za TOPM i 60 dana za HHH-UKM) potvrdili su cikličnost razvijene tehnologije sa implementiranim principima održivosti. Nakon desorpcije, boje su podvrgnute fotokatalitičkoj degradaciji ili enzimskoj dekolorizaciji, dok su Pb2+, As(V) i Cr(VI) tretirani precipitacijom, radi smanjenja negativnog ekološkog uticaja. Stabilizacija Pb2+ izvedena je u obliku olovo-ftalata, koji je korišćen kao punilac za kompozite na bazi nezasićene poliestarske smole (NPSM). Ovi kompoziti su obogaćeni akrilno modifikovanim kraft ligninom (A-KL), čime su postignuta poboljšana mehanička i vatrootporna svojstva materijala. Rezultati sugerišu na visok afinitet membrana prema zagađivačima, bezbednosti životne sredine i održivosti jer su proizvedene od obnovljivih i otpadnih materijala.

This doctoral dissertation focuses on sustainable technologies for producing lignocellulosic membranes designed to remove anionic and cationic pollutants from water, with the goal of protecting the environment and enhancing the quality of life. Two types of functionalized cellulose-based membranes were investigated. The first membrane (TOPM) was obtained from cotton linters oxidized with 2,2,6,6-tetramethylpiperidin-1-oxyl radical. The second membrane (HHH-UKM) was developed through the cationic functionalization of waste hemp fibers. All materials were characterized using spectroscopic, microscopic, and analytical techniques. The adsorption properties of the membranes were studied in both batch and flow systems. The applied adsorption isotherms described the interaction between adsorbate and adsorbent at equilibrium, confirming the high adsorption capacities of the membranes for removing cationic and anionic pollutants. After multiple desorption cycles, both membranes were subjected to biodegradability tests. The results (70 days for TOPM and 60 days for HHH-UKM) confirmed the cyclic nature of the developed technology, aligned with sustainability principles. After desorption, the dyes underwent photocatalytic degradation or enzymatic decolorization, while Pb2+, As(V), and Cr(VI) were treated through precipitation to mitigate their environmental impact. Pb2+ was stabilized in the form of lead-phthalate, which was used as a filler for composites based on unsaturated polyester resin (NPSM). These composites were enriched with acrylate-modified kraft lignin (A-KL), resulting in improved mechanical and fire-resistant properties. The results indicate a strong affinity of the membranes for pollutants, as well as environmental safety and sustainability, given that they were produced from renewable and waste materials.

pamučni lintersi, konopljina vlakna, mehanizam adsorpcije, anjonski zagađivači, katjonski zagađivači, poliestarska smola, mehaničke karakteristike, biodegradabilnost, enzimatska dekolorizacija

cotton linters, hemp fibers, adsorption mechanism, anionic pollutants, cationic pollutants, polyester resin, mechanical properties, biodegradability, enzymatic decolorization

677.13:66.017/.018:628.161.2 (043.3)

Tekst