Development of a method for the determination of dyes with a spectrophotometer

Raznolikost strukture barvil predstavlja oviro pri odločanju, katera tehnologija bi bila najbolj primerna za njihovo eliminacijo iz odpadnih vod, v zadnjem času pa je veliko zanimanja za napredne oksidacijske procese in njihov mehanizem delovanja, ki ga sestavlja sproščanje reaktivnih molekul, ki vsebujejo kisik. Prisotne morajo biti v zadostnih količinah, da z njimi lahko očistimo odplake. V skladu s tem se je zasnovala ideja o kombinaciji okolju prijaznih metod z izvedljivimi in stroškovno učinkovitimi postopki, katerih najbolj zanimiv primer je kavitacija. V diplomskem delu smo želeli razviti metodo, ki bi, skupaj s hidrodinamično kavitacijo, lahko določila, koliko barvila smo uspešno odstranili. Izbrali smo si dve barvili, metilen modro in reaktivno rdeče 120, ter vsakega posebej redčili, da smo dobili različno koncentrirane raztopine, ki smo jim s spektrofotometrom izmerili absorbance ter glede na dobljene meritve izrisali umeritvene krivulje. Istočasno smo naredili še raztopine z različnimi koncentracijami vodikovega peroksida in ga prav tako analizirali v spektrofotometru. V drugem delu eksperimentalnega dela smo se osredotočili na hidrodinamično kavitacijo in njen učinek na odstranjevanje barvila reaktivno rdeče 120 v prisotnosti vodikovega peroksida.The diversity of the structure of dyes represents an obstacle in deciding which technology would be the best example for their elimination from wastewater, and recently there has been a lot of interest in advanced oxidation processes and their mechanism of action, which consists in the release of reactive molecules containing oxygen. They must be present in sufficient quantities so that we can clean the sewage with them. Accordingly, the idea of combining environmentally friendly methods with feasible and cost-effective procedures was conceived, the most interesting example of which is cavitation. In the thesis, we wanted to develop a method that, together with hydrodynamic cavitation, could determine how much dye was successfully removed. We chose two dyes, Methylene blue and Reactive red 120, and diluted each individually to obtain solutions of different concentrations, whose absorbance was measured with a spectrophotometer and we also plotted the trendlines based on the obtained measurements. At the same time, we made solutions with different concentrations of hydrogen peroxide and also analyzed it in a spectrophotometer. In the second part of the experimental work, we focused on hydrodynamic cavitation and its effect on the removal of Reactive red 120 dye in the presence of hydrogen peroxide