Degradação de paracetamol por fotólise direta e H2O2/UV em reator tubular

Abstract

Population growth along with industrial and agricultural activities have contributed to the generation of pollutants in water resources, many with their toxicity still unknown. Emerging micro-pollutants such as drugs, hormones and pesticides have the ability to maintain their active principles in aqueous medium even at low concentrations, from ng.L-1 to µg.L-1 , and conventional wastewater treatment systems often do not. are able to remove these substances. Faced with this problem, Advanced Oxidative Processes have proven to be a good alternative to degrade these micro pollutants. Within this problem this study aimed to evaluate the degradation of Paracetamol by direct photolysis and H2O2/UV in a tubular reactor operating such as a batch reactor and to study the toxicity of the products formed against Artemia salina. A 2² experimental design was made with the triplicate center point where the variables studied were time (60, 90 and 120 minutes) and flow (125, 250 and 375 L.h-1). For the toxicological test triplicate tests were performed for each sample from the AOP experiments, where 15 specimens of A. salina with light and constant aeration system were inserted into each test tube for 24 hours. The maximum conversion obtained by the direct photolysis method was 7.45% while for the H2O2/UV method was 86.65% for the 2 hour time in both processes, where the flow and the effect of this variable with time were not significant for the 95% confidence interval and can be neglected. The samples from the direct photolysis method showed high mortality against Artemia salina, reaching 91.11% in one of the tests, indicating that Paracetamol degradation products are toxic. For H2O2/UV samples it was not possible to perform the toxicity test due to the presence of remaining hydrogen peroxide