Unit:
Κατεύθυνση Ανόργανη Χημεία και Εφαρμογές της στη ΒιομηχανίαLibrary of the School of Science
Supervisors info:
Πατρίνα Παρασκευοπούλου, Αναπληρώτρια Καθηγήτρια, Τμήμα Χημείας ΕΚΠΑ,
Παναγιώτης Κυρίτσης, Καθηγητής Τμήμα Χημείας ΕΚΠΑ,
Κωνσταντίνος Μεθενίτης, Αναπληρωτής Καθηγητής Τμήμα Χημείας ΕΚΠΑ
Original Title:
Δέσμευση και απομάκρυνση υδραργύρου και χρωστικών από υδατικά περιβάλλοντα με χρήση αεροπηκτωμάτων αλγινικού ασβεστίου δικτυωμένου με πολυουρία
Translated title:
Capture and removal of mercury and dyes from aqueous environments using polyurea-crosslinked calcium alginate aerogels
Summary:
Ιn this master's thesis, new nanoporous materials, polyurea-crosslinked calcium alginate (X-Ca-alg) aerogels, were studied, which can adsorb heavy metals, such as lead, uranium, europium, thorium etc. The purpose of the present study is to investigate the sorption capacity of these aerogels towards Hg2+ ions in concentrations encountered in contaminated waters (in the ppb range), and various dyes, cationic (methylene blue and crystal violet) or ionic (methyl orange and Congo red). X-Ca-alg aerogels were characterized by spectroscopic methods (FTIR) and thermogravimetric analysis (TGA), while the porous network was probed by N2-sorption. X-Ca-alg aerogels have a high specific surface area (322 m2/g) and high porosity (93% v/v) and are mainly macroporous materials, with a percentage of mesoporosity and a small percentage of microporosity. The capacity of X-Ca-alg towards Hg2+ removal from aqueous solutions at room temperature was studied under different experimental conditions, such as different pH values, adsorbent dose, initial concentrations of Hg2+, or contact time of the adsorbent with the solution. In the concentration range observed in real contaminated samples (50-180 ppb), the removal of Hg2+ is higher than 85%. Also, X-Ca-alg aerogels can efficiently remove Hg2+ from industrial wastewater (71%). Regarding dyes, the sorption capacity of X-Ca-alg aerogels was found equal to 0.054 mol kg-1 for methylene blue and 8.4×10-3 mol kg-1 for crystal violet (from Langmuir isotherms), while these materials do not adsorb the anionic dyes methyl orange and Congo red.
Main subject category:
Science
Keywords:
alginates, polyurea, polyurea crosslinked alginate aerogels (X-alginates), adsorption, mercury, dyes, methylene blue, crystal violet, aerogels, water decontamination, wastewater
Number of references:
157
File:
File access is restricted until 2026-05-25.
ΔΙΠΛΩΜΑΤΙΚΗ ΕΡΓΑΣΙΑ.pdf
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File access is restricted until 2026-05-25.
