Advanced oxidation treatment of pentoxifylline in aqueous solutions

Abstract

The degradation of pentoxifylline (PTX) using H2O2, UV, H2O2/UV, Fenton and photo-Fenton processes has been examined in aqueous solutions. The influence of oxidation agent and initial PTX concentration, on H2O2, H2O2/UV, Fenton and photo-Fenton reactions was investigated. The addition of inorganic ions (Cl-, NO3-, SO4 2and CO3 2-) on the degradation efficiency of PTX was tested for H2O2/UV, Fenton and photo-Fenton processeses. The results indicate that the photo-Fenton reaction is the most sufficient for PTX removal. The complete pharmaceutics decomposition is achieved after 5 min under optimized concentration of FeSO4•7H2O and H2O2. The degradation of PTX is inhibited in the presence of inorganic matter in H2O2/UV and Fenton reaction. In the photo-Fenton process addition of above compounds does not affect the reaction rate. Structures of ten products of photo-Fenton reaction have been proposed.

Degradation kinetics and mechanism of pentoxifylline by ultraviolet activated peroxydisulfate

“…3 , after 30 min about 20% drug is decomposed) as well as combined system hydroxyl radical/UV (after 10 min residual concentration of PTX was detected). 17 As a consequence, it should be assumed that in this case the mechanism is much less explicit. The participation of hydroxyl radicals cannot be excluded given that the major changes take place in the first five minutes when the pH of the reaction medium is 9.8.…”

“…Several techniques such as non-thermal plasma, 13 electrochemical oxidation, 14 oxidation with chloride dioxide, 15 ozone and O 3 /H 2 O 2 , 16 H 2 O 2 , H 2 O 2 /UV, Fenton's and photo-Fenton processes where used to degrade PTX. 17,18 However, the reaction of ultraviolet-activated peroxydisulfate has not been considered.…”